Tooth Staining, Transparency and Enameling

Abstract

This article describes a method for making a dental restoration for a patient, comprising: generating or receiving a model of at least a portion of a patient's tooth based on both near-infrared wavelength data and at least one visible light wavelength data, the model including a representation of the outer surface of the patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the dentin; the model including the thickness, shape, and distribution of the enamel and dentin; estimating one or more of the following values ​​based on the model: light absorption, light reflection, light transmission, and light scattering for one or more visible light wavelengths of the patient's tooth and the enamel region extending from the outer surface of the patient's tooth to the patient's dentin; and sending information for making a dental restoration, wherein the surface and internal structure of the dental restoration have optical properties based on the estimated values. The method can provide a technical solution to help create a dental restoration that more closely resembles a natural tooth (including its internal optical structure).

Description

[0001] This application is a divisional application of the Chinese patent application with application number 201880050561.9.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This patent application claims priority to U.S. Provisional Patent Application No. 62 / 537,941, filed on July 27, 2017, entitled “TOOTH SHADING, TRANSPARENCY AND GLAZING,” and U.S. Provisional Patent Application No. 62 / 662,961, filed on April 26, 2018, entitled “TOOTH SHADING, TRANSPARENCY AND GLAZING,” the entire contents of both of which are incorporated herein by reference.

[0004] This patent application also references U.S. patent application No. 15 / 662,234, filed on July 27, 2017, entitled “INTRAORAL SCANNER WITH DENTAL DIAGNOSTICS CAPABILITIES,” the entire contents of which are incorporated herein by reference.

[0005] Incorporation by reference

[0006] All publications and patent applications mentioned in this specification are herein incorporated by reference in their entirety to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference. Technical Field

[0007] The methods and apparatus described herein may relate to dental implants (e.g., restorations such as artificial teeth, caps, dentures, veneers, and bridges) with more realistic coloring, shading, and transparency. Specifically, a method of manufacturing a dental implant using an optical scanner is described herein that generates a model of a patient's teeth, the model including a three-dimensional surface representation of the patient's teeth, a 3D volume model (which shows internal features including contours, density, and transparency), and color. Background Art

[0008] Recreating the exact visual appearance of teeth, dental reconstructions, and dental veneers for implants is a challenge faced by the dental restoration industry. Matching one or more implants (e.g., artificial restorations such as dentures, dental veneers, etc.) to a patient's natural dentition can be difficult and may require communication between the dentist or dental technician and possibly a separate laboratory. The natural appearance of ceramics is difficult to replicate, especially when relying on the clinician to describe or adequately explain what he or she sees during the colorimetric process. Typically, the first part of the colorimetric process may be to define the color, chromaticity, and transparency of the original tooth. However, attempts to define the color of opaque surfaces are particularly complicated due to the transparency of the tooth and the internal structure of the tooth that contains materials with different optical properties (e.g., enamel and dentin).

[0009] Traditionally, tooth coloring is usually performed by acquiring the tooth surface appearance from the outside using an RGB sensor or a spectral sensor. Typically, such measurements may provide 1 to 3 color areas for each tooth, and define up to approximately 20 shades. In addition, tooth color restoration can be performed by taking an image using an SLR camera (which can be manually compared to a reference color palette), and fine coloring of dental implants to resemble this image is usually done manually, without any digital detailed data involved in the process.

[0010] In restorative treatment, restorative implants (e.g. crowns and bridges, etc.) may require information about the color mapping, coloration and transparency of (single or multiple) teeth so that the resulting implant can have a suitable glazing.

[0011] Methods, systems, and / or computer-readable media are described herein that can address the issues raised above. Summary of the invention

[0012] The systems, methods, and / or computer-readable media described herein provide technical solutions to the highly technical problem of machine generation of dental restorations. In particular, these systems, methods, and / or computer-readable media may provide technical solutions to help make dental restorations that more closely resemble natural teeth (including their internal optical structures). These systems, methods, and / or computer-readable media may facilitate actually rendering teeth including their internal optical structures, and applying these renderings (e.g., digital models) to the manufacture of dental restorations.

[0013] Any of the methods and apparatus (systems and devices, etc., including software, hardware and / or firmware) described herein can be used to make a dental restoration for a patient so that the dental restoration has optical properties that match the patient's teeth. For example, the methods and apparatus described herein can be used to create a visible light volume model in a three-dimensional context that includes optical properties based on the patient's existing teeth, and the visible light volume model can be used to generate a dental restoration using the optical properties of the visible light volume model. Optical properties are described for the surface and internal volume of one or more teeth, which can be teeth adjacent to or similar to the teeth to be restored by the dental restoration. In some variations, a volume model of all or part of a dental restoration can be generated, and the optical properties of the dental restoration volume model can be derived from the visible light volume model.

[0014] Typically, dental restorations can include restorative implants such as crowns, veneers, bridges, etc. Any of these restorative implants can include a glaze as part of the restoration (e.g., a veneer, including a ceramic veneer) to simulate tooth enamel.

[0015] Any of the methods, systems, and / or computer-readable media described herein may include the use of a three-dimensional (3D) oral scanner, which may also be referred to as an intraoral scanner. The methods and apparatus may be used with any suitable intraoral scanner, and in particular with those intraoral scanners that scan using near infrared and visible light, either separately (including sequentially) or concurrently / simultaneously. An example of an intraoral scanner that may be used is described, for example, in U.S. patent application Ser. No. 15 / 662,234, filed on July 27, 2017, and entitled “INTRAORAL SCANNER WITH DENTAL DIAGNOSTICS CAPABILITIES.”

[0016] A volume model generally refers to a digital representation of a three-dimensional space (e.g., a volume). In particular, a volume model of all or part of a tooth is described herein. A volume model generally can be a solid model or a shell / boundary model. A volume model can be a digital map representing a three-dimensional region, for example, a volume model can include voxels.

[0017] The methods, systems and / or computer readable media described herein typically generate a 3D body model that includes one or more optical properties of a tooth as part of the 3D body model. Any optical property may be used, including: light absorption, light reflection, light transmission, and light scattering. Other optical properties may include hue, transparency, translucency, opalescence, chroma, brightness, gloss, and fluorescence. These optical properties may overlap and / or may be alternative representations of each other and / or may be derived from other optical properties. For example, translucency may be represented as a property of light scattering and light reflection.

[0018] In general, reflection, transmission and absorption may depend on the wavelength of the radiation affected. Thus, these three processes can be quantified for monochromatic or polychromatic radiation (and the spectral distribution of the incident radiation can be specified). In addition, reflectivity, transmission and absorption may also depend on the polarization and geometric distribution of the incident radiation, which can also be specified.

[0019] Light reflectance (e.g., reflectivity) can be the ratio of the reflected radiant power to the incident radiant power. For some area element of a reflective surface, the (differential) incident radiant power can be the irradiance of the surface multiplied by the size of the surface element. The total reflectivity can be further subdivided into regular reflectivity and diffuse reflectivity, which can be derived from the ratio of the regularly (or specularly) reflected radiant power and the diffusely reflected radiant power to the incident radiant power, respectively.

[0020] Light absorption can refer to the conversion of radiant power applied to a material into another type of energy (usually heat) through interaction with the material. Absorption may be of a specific wavelength. The absorptivity of a medium can be defined by the ratio of the absorbed radiant power to the incident radiant power.

[0021] The light transmission (or transmittance) of a medium can be defined as the ratio of the transmitted radiant power to the incident radiant power. The total transmittance can be further subdivided into regular transmittance and diffuse transmittance, which can be derived by the ratio of the regularly (or directly) transmitted radiant power and the diffusely transmitted radiant power to the incident radiant power, respectively.

[0022] Reflection is the process by which electromagnetic radiation is returned at a boundary between two media (surface reflection) or inside a medium (volume reflection), while transmission is the passage of electromagnetic radiation through a medium. Both processes may be accompanied by diffusion (also called scattering), which is the process of deflecting a unidirectional beam of light into multiple directions. When no diffusion occurs, reflection or transmission of a unidirectional beam of light produces a unidirectional beam according to the laws of geometric optics. Reflection, transmission, and scattering leave the frequency of the radiation unchanged, although the Doppler effect may cause a frequency change when the reflecting material or surface moves. Reflectivity, transmittance, and absorptivity are dimensionless. Quantities such as reflectivity and transmittance are used to describe the optical properties of materials. These quantities can apply to either composite or monochromatic radiation.

[0023] For example, a method of making a dental restoration for a patient is described herein so that the dental restoration has optical properties that match the optical properties of the patient's teeth. The method may include: receiving a visible light volume model of at least a portion of the patient's teeth, wherein the volume model includes a representation of an outer surface of the patient's teeth and an enamel region extending from the outer surface of the patient's teeth to the dentin; further, wherein the visible light volume model includes an indication of two or more of: light absorption, light reflection, and light scattering of the outer surface, dentin surface, and enamel region of the patient's teeth by one or more wavelengths of light; and making a dental restoration based on the visible light volume model, wherein the surface and internal structure of the dental restoration have optical properties based on the visible light volume model.

[0024] Fabricating the dental restoration may include generating a volume model of the dental restoration comprising a plurality of voxels, wherein the voxels of the volume model of the restoration have values ​​based on values ​​of the voxels of the visible light volume model. The shape of the dental restoration may be predefined or selected, and the optical properties may be provided by the visible light volume model of one or more teeth of the patient.

[0025] Typically, based on an unrestored tooth and / or one or more adjacent teeth, a dental restoration can be manufactured so that its internal structure and surface have the same optical properties as the patient's actual teeth, so that the dental restoration looks similar to the patient's natural teeth. When manufacturing the actual dental restoration, the dental restoration can be formed manually (e.g., guided by a technician), semi-manually, or automatically (including by 3D printing technology) using the techniques described herein. Typically, for corresponding positions and / or depths within the tooth volume, manufacturing a dental restoration can give each voxel of the restoration a similar optical value compared to a reference tooth voxel (e.g., a voxel from a visible light volume model).

[0026] The dental restoration can be manually made from the visible light body model (e.g., by selecting a material having optical properties corresponding to the optical properties of the surface and internal structure of a portion from the visible light body model), or can be automatically made from the visible light body model (including forming a digital model of the dental restoration having optical properties derived from the visible light body model).

[0027] Typically, the step of receiving a visible light volume model may include receiving the visible light volume model from a memory, from a transmission, and / or from within the same system, for example by generating the visible light volume model. The received visible light volume model may be a visible light volume model of at least a portion of the patient's teeth adjacent to the patient's teeth to be restored by the dental restoration. Optionally, the received visible light model may be a visible light volume model for the teeth to be restored by the dental restoration and / or a visible light volume model for teeth corresponding to teeth located on both sides of the jaw where the teeth to be restored are located.

[0028] For example, receiving the visible light volume model may include generating the visible light volume model. Thus, receiving the visible light volume model may include: generating or receiving a volume model of at least a portion of a patient's teeth from a three-dimensional (3D) oral scanner that operates using both near infrared wavelengths and visible light wavelengths, wherein the volume model includes a representation of an outer surface of the patient's teeth and an enamel region extending from the outer surface of the patient's teeth to the patient's dentin; estimating values ​​of one or more of: light absorption, light reflection, light transmission, and light scattering for one or more visible light wavelengths for a plurality of voxels defining the outer surface of the patient's teeth and the enamel region extending from the outer surface of the patient's teeth to the patient's dentin; and adding the estimated values ​​to the volume model to form the visible light volume model.

[0029] Estimating the values ​​may include estimating values ​​of two or more of: light absorption, light reflection, light transmission, and light scattering for each of a plurality of voxels defining an outer surface of a patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin. Estimating the values ​​may include estimating values ​​of one or more of: light absorption, light reflection, light transmission, and light scattering for each of a plurality of voxels defining an outer surface of a patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin at three or more visible light wavelengths. The three or more visible light wavelengths include one or more red wavelengths, green wavelengths, and blue wavelengths.

[0030] In some embodiments, the estimation includes estimating values ​​of one or more of: light absorption, light reflection, light transmission, and light scattering at one or more visible light wavelengths for each of a plurality of voxels defining an outer surface of a patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin by setting the values ​​for one or more of the following to predetermined prior values.

[0031] Any of these methods may also include estimating values ​​of one or more of the following: light absorption, light reflection, light transmission, and light scattering for one or more visible light wavelengths for each of a plurality of voxels defining an outer surface of a patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin by setting one or more of the following values ​​to predetermined prior values ​​determined by parameter estimation.

[0032] The estimation may include estimating one or more of the following values ​​by iteratively estimating based on the reconstructed volume and camera position compared to the RGB data recorded when scanning the patient's teeth using an intraoral scanner to generate a volume model: light absorption, light reflection, light transmission, and light scattering of one or more visible light wavelengths for each of a plurality of voxels defining the outer surface of the patient's teeth and the enamel region extending from the outer surface of the patient's teeth to the patient's dentin to determine a value close to the optical property. In some variations, the estimation includes estimating one or more of the following values ​​by setting one or more of the following values ​​to a predetermined prior value: light absorption, light reflection, light transmission, and light scattering of one or more visible light wavelengths for each of a plurality of voxels defining the outer surface of the patient's teeth and the enamel region extending from the outer surface of the patient's teeth to the patient's dentin, the predetermined prior value being determined from a representative patient population. Wherein, the prior value is selected using one or more of the following: measured RGB data, volume information, and patient information recorded when scanning the patient's teeth using an intraoral scanner to generate a volume model. The volume information may include a path length from the tooth surface through the enamel to the dentin. The patient information may include one or more of: patient age, gender, and estimated jaw shape.

[0033] In any of these variations, the method may further include dividing the volume model into multiple sub-regions before estimating values ​​of one or more of the following: light absorption, light reflection, light transmission, and light scattering for one or more visible light wavelengths for the outer surface of the patient's teeth and the enamel region extending from the outer surface of the patient's teeth to the patient's dentin.

[0034] Systems, methods, and computer-readable media that can actually render teeth are described herein, including visible optical structures that can be used to generate dental restorations. For example, these systems may include a non-transitory computer-readable medium that stores instructions for being executed by a processor to prepare a dental restoration having optical properties that match the optical properties of a patient's teeth. Any of these systems, methods, and computer-readable media may include: generating or receiving a volume model of at least a portion of a patient's teeth from a three-dimensional (3D) oral scanner that operates using both near-infrared wavelengths and visible light wavelengths, wherein the volume model includes a representation of the outer surface of the patient's teeth and an enamel region extending from the outer surface of the patient's teeth to the patient's dentin; estimating the values ​​of one or more (e.g., two or more, three or more, etc.) optical properties such as: light absorption, light reflection, light transmission, and light scattering of one or more visible light wavelengths for multiple voxels that define the outer surface of the patient's teeth and the enamel region extending from the outer surface of the patient's teeth to the patient's dentin; adding the estimated values ​​to the volume model to form a visible light volume model; and making a dental restoration based on the visible light model.

[0035] A body model of at least a portion of a patient's teeth may be received, for example, by a processor, and the body model may include a plurality of voxels defining an outer surface of the patient's teeth and an enamel region extending from the outer surface of the patient's teeth to the patient's dentin. The body model may be received by a separate device (e.g., a dental scanner) including a dental scanner (e.g., an intraoral scanner) capable of forming a 3D body model, as more fully described in U.S. patent application Ser. No. 15 / 662,234, filed Jul. 27, 2017, entitled “INTRAORAL SCANNER WITH DENTAL DIAGNOSTICS CAPABILITIES,” which is incorporated herein by reference in its entirety. In some embodiments, the processor is part of the scanner or is coupled to the scanner. Alternatively or additionally, the body model may be stored in a memory accessed by the processor.

[0036] For example, a (3D) oral scanner can scan a patient's teeth concurrently or simultaneously at both near infrared wavelengths and visible light wavelengths. The scan can generate a volume model so that the initial volume model includes a representation of the outer surface of the patient's teeth and an enamel area extending from the outer surface of the patient's teeth to the patient's dentin. The penetration depth may depend on the scan. Near infrared light can penetrate the enamel to at least reach the dentin, so the volume model can be reconstructed by near infrared scanning to provide a high-precision three-dimensional model of the scanned area, including the thickness, shape, and distribution of the enamel and / or dentin. Visible light scanning can be used in conjunction with penetrating near infrared scanning, and the visible light scanning can include one or more (e.g., RGB) wavelengths.

[0037] One or more of the following values ​​may be estimated from the volume model: light absorption, light reflection, light transmission, and light scattering. In some variations, it may be beneficial to estimate the values ​​of two or more of light absorption, light reflection, light transmission, and light scattering (e.g., estimate the values ​​of: light absorption and light reflection; light absorption and light transmission; light absorption and light scattering; light reflection and light transmission; light reflection and light scattering; and / or light transmission and light scattering). In some variations, three or more of light absorption, light reflection, light transmission, and light scattering may be estimated (e.g., light absorption, light reflection, and light transmission; light absorption, light reflection, and light scattering; light absorption, light transmission, and light scattering; and / or light reflection, light transmission, and light scattering). In some variations, all four of light absorption, light reflection, light transmission, and light scattering may be estimated.

[0038] Estimates of light absorption, light reflection, light transmission, and light scattering may be derived based on dentin locations within the teeth extracted from the volume model. Some or all of the optical properties of light absorption, light reflection, light transmission, and light scattering may be estimated for multiple visible light wavelengths, for voxels defining at least a portion of the volume model (e.g., voxels defining an outer surface of a patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin). For example, visible light wavelengths may be provided for one or more of red, green, and blue wavelengths, and in some variations, each of red, green, and blue may be provided.

[0039] An estimate of one or more of the following can be provided by setting values: light absorption, light reflection, light transmission, and light scattering for voxels (and / or voxel regions) that define the outer surface of the patient's tooth and the enamel region extending from the outer surface of the patient's tooth to the patient's dentin. For example, estimating the values ​​may include setting the value for the outer surface of the tooth and the value for the volume of enamel between the tooth and the dentin to a predetermined value (e.g., a priori value), which may be selected based on (one or more) visible light wavelengths provided in the original volume data. In some variations, the processor may reference a database or memory including values ​​for one or more optical properties (e.g., light absorption, light reflection, light transmission, and light scattering). The value of the optical property may be determined by an average, a group value, or a similar value. When setting values ​​for one or more optical properties for a voxel, the value may be specified based on correlation with similar surface values. For example, a value may be specified or set for the outer surface by assuming basic values ​​(e.g., a priori features) for the outer surface and / or enamel and / or dentin surface. The 3D volume model may include a model of the outer surface of a single or multiple teeth, and one or more optical parameter values ​​may be set for corresponding voxels based on the fit of assumed parameters (modeling parameters) to the measured values ​​included in the volume model.

[0040] For example, one or more optical properties may be estimated based on assumed parameters that are set, and these assumed parameters may be tested against estimated parameter estimates, or similar methods may be used to estimate parameters from a volume model to generate an estimated image that may be compared to an actual image acquired by scanning to determine a 3D volume model, or derived from a 3D volume model. For example, assuming parameters for tooth enamel, these assumed parameters may be used to generate an expected image of the tooth, which may be compared to actual data from the patient contained in the original volume model; by comparing the fit of the actual measured data to the expected value model, a technique (e.g., parameter estimation, etc.) may be used to change the assumed values ​​of one or more optical properties to improve the fit between the measured data and the estimated (one or more) images.

[0041] Thus, by setting the values ​​to predetermined prior values, one or more optical properties (e.g., light absorption, light reflection, light transmission, and light scattering) for one or more visible light wavelengths for each of a plurality of voxels defining the outer surface of a patient's tooth and an enamel region extending from the outer surface of the tooth to the dentin can be estimated. The final estimate can be refined by comparing an image of the modeled tooth generated using these values ​​with an image from a volumetric model. Thus, one or more of the following values ​​can be set to predetermined prior values ​​determined by parameter estimation: light absorption, light reflection, light transmission, and light scattering for one or more visible light wavelengths for each of a plurality of voxels defining the outer surface of a patient's tooth and an enamel region extending from the outer surface of the tooth to the dentin of the patient. For example, a value approximating an optical property can be determined by iterating based on the reconstructed volume and the position of the camera compared to the RGB data recorded when scanning the patient's teeth using an intraoral scanner to generate a volumetric model.

[0042] In some variations, the values ​​of one or more optical properties may be set within a visible light volume model by setting the values ​​of the one or more optical properties to predetermined prior values ​​determined from a representative patient population, wherein the prior values ​​are selected using one or more of the following: measured RGB data, volume information, and patient information recorded when scanning the patient's teeth using an intraoral scanner to generate the volume model. Optionally or additionally, setting the values ​​to predetermined prior values ​​may be determined from a representative patient population, wherein the prior values ​​are selected using one or more of the following: measured RGB data, volume information, and patient information recorded when scanning the patient's teeth using an intraoral scanner to generate the volume model. For example, the volume information may include a path length from the tooth surface through the enamel to the dentin. The patient information may include one or more of the following: patient age, gender, and estimated jaw shape.

[0043] Thus, as described herein, estimating the value of one or more optical properties may include setting voxels (or voxel regions) in the region between the tooth surface and the dentin to one or more prior values. For example, the prior values ​​may be based on average light absorption and light scattering per wavelength (color); images (e.g., visible light images) taken when scanning to form an initial three-dimensional volume model may be used to estimate the optical properties of the surface and enamel. Specifically, the surface and enamel optical property values ​​may be estimated from the prior values ​​using an iterative method that solves for the optical properties (e.g., absorption, reflection, and transmission) based on the reconstructed volume and the position of the camera compared to the actual RGB image taken by the scanner.

[0044] For example, the present invention also describes a method for making a dental restoration for a patient so that the dental restoration has optical properties that match the optical properties of the patient's teeth. The method may include: generating or receiving a volume model of at least a portion of the patient's teeth from a three-dimensional 3D oral scanner operating at both near-infrared wavelengths and at least one visible light wavelength, wherein the volume model includes a representation of the outer surface of the patient's teeth and an enamel region extending from the outer surface of the patient's teeth to the dentin; wherein the volume model includes the thickness, shape, and distribution of the enamel and dentin; estimating one or more of the following values ​​based on the volume model: light absorption, light reflection, light transmission, and light scattering for one or more visible light wavelengths for the patient's teeth and the enamel region extending from the outer surface of the patient's teeth to the patient's dentin; adding the estimated values ​​to the volume model to form a visible light volume model; and sending information for making a dental restoration, wherein the surface and internal structure of the dental restoration have optical properties based on the visible light volume model.

[0045] In any of the methods, systems, and / or computer-readable media described herein, the volume model can be divided into a plurality of sub-regions prior to estimating values ​​of one or more optical properties (e.g., light absorption, light reflection, light transmission, and light scattering) at one or more visible light wavelengths. The sub-regions can include any number of voxels (e.g., one or more) and can be grouped based on the shape or morphology of the tooth. For example, regions of tooth enamel (e.g., isothermal regions and / or regions at a fixed range or distance from the surface) can be sub-regions.

[0046] The methods, systems and / or computer readable media described herein can form a model, such as a visible light volume model, which includes values ​​of one or more of the optical properties (e.g., light absorption, light reflection, light transmission, and light scattering) of one or more visible light wavelengths for the outer surface of the patient's teeth and the enamel region extending from the outer surface of the patient's teeth to the patient's dentin. The visible light volume model can also include the original volume model. A dental restoration can be formed from the visible light volume model.

[0047] For example, the present invention describes a non-transitory computer-readable medium storing instructions for execution by a processor to prepare a dental restoration having optical properties that match the optical properties of a patient's teeth; wherein, when the instructions are executed, the processor: generates or receives a volume model of at least a portion of the patient's teeth from a three-dimensional 3D oral scanner operating at both near-infrared wavelengths and at least one visible light wavelength, wherein the volume model includes a representation of the outer surface of the patient's teeth and an enamel region extending from the outer surface of the patient's teeth to the dentin; wherein the volume model includes the thickness, shape and distribution of the enamel and dentin; estimates one or more of the following values ​​based on the volume model: light absorption, light reflection, light transmission and light scattering for one or more visible light wavelengths for the patient's teeth and the enamel region extending from the outer surface of the patient's teeth to the patient's dentin; adds the estimated values ​​to the volume model to form a visible light volume model; and sends information for manufacturing a dental restoration, wherein the surface and internal structure of the dental restoration have optical properties based on the visible light volume model.

[0048] For example, described herein is a non-transitory computer-readable medium storing instructions for execution by a processor, which instructions, when executed, cause the processor to perform the following operations: generate or receive a volume model of at least a portion of a patient's teeth, wherein the volume model includes a representation of an outer surface of the patient's teeth and an enamel region extending from the outer surface of the patient's teeth to the patient's dentin; estimate values ​​for one or more of: light absorption, light reflection, light transmission, and light scattering for one or more visible light wavelengths for the outer surface of the patient's teeth and the enamel region extending from the outer surface of the patient's teeth to the patient's dentin; and add the estimated values ​​to the volume model to form a visible light volume model.

[0049] In some variations, estimating the value of one or more of the optical properties may include setting the outer surface and an enamel region between the outer surface and the dentin to predetermined (prior) values, and solving for the optical properties of the surface by using volume information (e.g., a path length from the tooth surface through the enamel to the dentin surface) to apply the measured RGB image data to the corresponding volume region. The predetermined value / prior value may be selected based on patient information (e.g., an estimated age of the patient based on the shape of the jaw, etc.), a set list of predetermined values / prior values ​​based on available restorative materials, etc.

[0050] For example, the present invention also describes a non-transitory computer-readable medium storing instructions for execution by a processor, which instructions, when executed, cause the processor to perform the following operations: generate or receive a volume model of at least a portion of the patient's teeth from a three-dimensional 3D oral scanner operating at both near-infrared wavelengths and at least one visible light wavelength, wherein the volume model includes a representation of the outer surface of the patient's teeth and an enamel region extending from the outer surface of the patient's teeth to the dentin; wherein the volume model includes the thickness, shape, and distribution of the enamel and dentin; estimate one or more of the following values ​​based on the volume model: light absorption, light reflection, light transmission, and light scattering for one or more visible light wavelengths for the patient's teeth and the enamel region extending from the outer surface of the patient's teeth to the patient's dentin; add the estimated values ​​to the volume model to form a visible light volume model; and send information for manufacturing a dental restoration, wherein the surface and internal structure of the dental restoration have optical properties based on the visible light volume model. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The novel features of the invention are set forth with particularity in the appended claims.The features and advantages of the invention may be better understood by referring to the following detailed description and the accompanying drawings, which set forth illustrative embodiments utilizing the principles of the invention.

[0052] Figure 1 is an example of a method for creating a visible light volume model that can be used to manufacture a dental restoration.

[0053] Figure 2 is an example of a system that can generate a visible light volume model that can be used to make a dental restoration. Therefore, a portion of the system can be referred to as a dental reconstruction manufacturing system.

[0054] Figure 3A An example of a 3D (color) intraoral scanner that may be adapted to generate a volume model of a subject's teeth as described herein, the volume model having an internal map (identified by near infrared) and an external (e.g., surface) Figure 2 Those that do include visible light wavelengths.

[0055] Figure 3B An example of an intraoral scanner configured to generate a model of a subject's teeth having both surface and internal features is schematically shown.

[0056] Figure 3CA schematic diagram of an intraoral scanner configured to perform both surface scanning (e.g., visible light, non-penetrating) and penetrating scanning using near infrared (IR) wavelengths is shown. The scanner includes polarizers and filters to block near infrared light reflected from tooth surfaces while still collecting near infrared light reflected from internal structures.

[0057] Figure 4A A prior art method of forming a dental implant is shown.

[0058] Figure 4B A method of forming a dental implant is shown by using an intraoral scanner operating at both non-penetrating (e.g., surface scanning and / or color scanning) wavelengths and penetrating (e.g., near infrared) wavelengths to determine a visible light volume model having one or more optical properties of voxels within a volume in addition to structural information of the tooth. DETAILED DESCRIPTION

[0059] Described herein are devices (systems and apparatus), automated methods and / or computer-readable media for assisting in creating dental restorations (e.g., dental implants) that closely resemble a patient's natural teeth, particularly including their internal optical structures. In general, the systems, methods and / or computer-readable media can actually render a model of a patient's (single or multiple) teeth, including the internal optical structures. The patient's teeth can be teeth to be repaired by a dental restoration, adjacent teeth, corresponding bilateral teeth, or other natural teeth of the patient. This model (which is referred to as a visible light body model) can be used manually or automatically to create high-precision dental restorations, such as artificial teeth, crowns, dentures, dental veneers, and bridges, etc., that have the same or similar optical properties as the patient's natural teeth.

[0060] Most dental restorative implants apply only surface properties. Such estimates fail to accurately approximate the visual properties of teeth (which may vary based on the lighting of the teeth), resulting in a poor match between the restorative implant and the patient's natural teeth, especially in environments with varying lighting. Teeth have specific optical properties, including color and transparency, which can be a function of both external and internal features. When creating a dental restoration, it is highly desirable to make the dental restoration have a realistic, and preferably customized, color and transparency that matches or is consistent with the patient's existing teeth. Visible light volume models can provide a model of a tooth (single or multiple) that can guide the formation of the dental restoration.

[0061] As described herein, a visible light volume model may include both a structural map of a volume of a patient's (single or multiple) teeth (which may form part or all of a dental restoration) and one or more optical properties associated with a region within the volume of the structural map. Although a variety of optical properties may be associated, one or more of the following may be particularly helpful for making a dental restoration: light absorption, light reflection, light transmission, and light scattering. Additional or alternative optical properties that may be used include: hue, transparency, translucency, opalescence, saturation, brightness, gloss, and fluorescence. These optical properties may be specific to one or more wavelengths (e.g., visible light wavelengths, such as red, green, and / or blue wavelengths or groups of wavelengths).

[0062] When a visible light volume model is used (automatically or manually) to generate a dental restoration, the structures and / or optical properties in the model can be used. A visible light volume model is a volume model that provides information about the external and internal structures; the addition of optical properties can then provide a guide or map for forming the restoration. The optical properties can be used to select materials for forming the dental restoration. In some variations, the optical properties can be used to select (one or more) materials to form the dental restoration. For example, the optical properties can match the optical properties of the materials (e.g., plastics, ceramics, dyes / colorants, etc.) used to form the dental restoration. In some variations, the system, method and / or computer-readable medium can automatically convert the optical properties provided in the visible light volume model into one or more materials that can be used. Optionally or additionally, the values ​​of the optical properties within the visible light volume model can be converted or adjusted to values ​​that can be used to select (one or more) materials for forming the dental restoration, or can simply be replaced with an indication (e.g., name, number, etc.) for (one or more) materials with the same or similar optical properties.

[0063] The visible light volume model can be a collection of voxels that describe the volume of the patient's (single or multiple) teeth. In some variations, as described in Example 1 below, the volume is determined directly from the patient's existing teeth, for example by scanning using an intraoral scanner. In other variations, the volume is a reconstructed volume based on another area of ​​the patient's (single or multiple) teeth. For example, when making a dental restoration of a patient's teeth, it may not be possible to scan the missing teeth. However, a 3D volume scan of other patient teeth (e.g., symmetrical teeth and / or adjacent teeth) can be used as a template for the visible light volume model of the dental restoration. Optionally, the visible light volume model can be a model of the patient's existing teeth, and the manufacturer can use the visible light volume model (manually or automatically) as a guide for forming the missing teeth and matching the internal structure (e.g., enamel and / or dentin) and optical properties.

[0064] The systems, methods, and / or computer-readable media described herein may provide more accurate information that can be used to form a restorative implant. The visible light volume model described herein may also be used for other purposes, not limited to the formation of dental restorations. For example, the visible light volume model may be used to track a patient's dental health, plan or track dental treatments, provide guidance to dentists during treatment of patients (e.g., performing fillings, oral surgery, etc.), and / or during cosmetic procedures such as teeth whitening.

[0065] Figure 1 is a general overview of an exemplary method for creating a visible light volume model (which may be performed by the system described herein) that may be used to fabricate a dental restoration. Optionally, a scan of at least a portion of a patient's teeth using both near infrared wavelengths and visible light wavelengths may be used to generate a 3D volume model that includes a representation 101 of an outer surface of the patient's teeth and an enamel region extending from the outer surface of the patient's teeth to the patient's dentin. Scan information (which includes images taken while scanning for either or both of the visible light wavelength(s) and the near infrared wavelength(s)) may be included in or as part of a 3D volume scan. The scan may be performed by an intraoral scanner that is part of the overall system or a separate system. The 3D volume model can then be received 103 by a processor (e.g., as described below with reference to a dental restoration manufacturing system) and used to estimate values ​​105 of one or more optical properties (e.g., light absorption, light reflection, light transmission, and light scattering, etc.) for one or more visible light wavelengths for a plurality of voxels defining an outer surface of the patient's tooth and an enamel region extending from the outer surface of the tooth to the dentin. The estimated values ​​of the optical properties can then be added to the 3D volume model to form a visible light volume model. Typically, the visible light volume model includes a plurality of voxels describing a 3D volume of a patient's (single or multiple) teeth, and at least some of these voxels (e.g., a region between the outer surface and the enamel, which is located between the outer surface and the dentin) contain information about the optical properties for one or more visible light wavelengths.

[0066] Figure 2201 is a diagram showing an example of a dental prosthesis manufacturing system 201, which is optionally shown as part of a larger modeling system 200. The modules of the dental prosthesis manufacturing system 201 may include one or more engines and data storage. The computer system may be implemented as an engine, a part of an engine, or implemented by multiple engines. As used herein, an engine includes one or more processors or a part of one or more processors. A part of one or more processors may include: some parts of hardware (e.g., a subset of registers) that are less than the entire hardware of any given one or more processors, a part of a processor dedicated to one or more threads of a multi-threaded processor, a time segment in which a processor is fully or partially dedicated to executing a portion of the functions of an engine, etc. In this way, the first engine and the second engine may have one or more dedicated processors, or the first engine and the second engine may share one or more processors with each other or with other engines. Depending on the specific implementation or other considerations, the engine may be centralized or its functions may be distributed. The engine may include hardware, firmware, or software embodied in a computer-readable medium for execution by a processor. The processor converts data into new data using implemented data structures and methods, such as described with reference to the drawings of this article.

[0067] The engine described herein or the engine by which the systems and devices described herein can be implemented can be a cloud-based engine. As used herein, a cloud-based engine is an engine that can use a cloud-based computing system to run applications and / or functions. All or part of the application and / or function can be distributed on multiple computing devices without being limited to only one computing device. In some embodiments, a cloud-based engine can execute functions and / or modules accessed by an end user through a web browser or a container application without having to install the functions and / or modules locally on the end user's computing device.

[0068] As used herein, a data store is intended to include a repository having any applicable data organization, including tables, comma-separated value (CSV) files, traditional databases (e.g., SQL), or other applicable known or convenient organizational formats. For example, a data store may be implemented, for example, as software embodied in a physical computer-readable medium on a dedicated machine, in firmware, in hardware, in a combination thereof, or in an applicable known or convenient device or system. Components related to data stores, such as database interfaces, may be considered part of the data store, part of some other system component, or a combination thereof, although the physical location and other characteristics of the components related to the data store are not critical to understanding the techniques described herein.

[0069] Data storage may include data structures. As used herein, a data structure is associated with a specific way of storing and organizing data in a computer so that it can be used efficiently within a given context. Data structures are typically based on the ability of a computer to retrieve and store data at any location in its memory, specified by an address, a bit string that itself can be stored in memory and manipulated by a program. Thus, some data structures are based on calculating the addresses of data items using arithmetic operations; while other data structures are based on storing the addresses of data items within the structure itself. Many data structures use both principles, sometimes combined in a meaningful way. The implementation of a data structure typically requires writing a set of programs that create and manipulate instances of the structure. The data storage described herein may be a cloud-based data storage. A cloud-based data storage is a data storage that is compatible with a cloud-based computing system and with an engine.

[0070] The dental restoration manufacturing system 201 may include a computer readable medium, a visible light volume model engine 205, one or more optical property estimation engines (e.g., light absorption estimation engine 207, light reflection estimation engine 209, light emission estimation engine 213, and light transmission estimation engine 211, etc.), and a priori value data storage 215. Additional data storage 217 may be included, such as reference patient information and / or material information. One or more modules of the dental restoration manufacturing system may be coupled to each other (e.g., via Figure 2 The exemplary coupling shown) or coupled to Figure 2 The computer-readable medium may include any computer-readable medium, including but not limited to a bus, a wired network, a wireless network, or some combination thereof.

[0071] The optical property estimation engine may implement one or more automated agents configured to learn optical property information-based matching from a 3D virtual representation of the subject's teeth (eg, other 3D body models).

[0072] Estimate one or more optical properties

[0073] In a first example, a restorative implant with more realistic optical properties can be made from a visible light volume model in which one or more optical properties of the outer surface and the region (or regions) between the outer surface and dentin of the volume model are estimated using structural information in the volume model, including the location of dentin within a tooth or portion of a tooth in the volume model. Volume data can be used to indicate where the dentin is located in the tooth relative to the outer surface, thereby providing an estimate of the thickness of the enamel. By using the morphology of the tooth or region of the tooth, including the thickness of the enamel and the location of the dentin in the enamel, and using optical information obtained or extracted from (one or more) visible light wavelengths acquired via scanning (such information being included as part of the volume model), optical properties (e.g., light absorption, light reflection, light transmission, and light scattering at one or more visible light wavelengths) of a tooth or tooth portion within the volume model can be determined for each of a plurality of voxels within the volume model.

[0074] For example, in some variations, the optical properties of the outer surface and the area between the outer surface and the dentin (and in some variations, including the dentin), the average light absorption and light scattering and / or scattering of each wavelength (e.g., color) can be estimated from (one or more) visible light images in a volume model (e.g., a visible light volume model engine) that is passed to a processor that operates to estimate the optical properties. For example, when the visible light images taken by the intraoral scanner used to generate the volume model are RGB images, these images can be used to estimate the optical properties of the surface and enamel. In some variations, the optical properties can be determined by assuming starting prior values ​​for (one or more) different regions of the tooth (including the outer surface, enamel, and in some cases dentin). For example, enamel at different depths can be set with different starting prior values ​​of one or more optical properties, or the enamel can be initially considered to be uniform and initially set to have the same prior values ​​for these one or more optical properties. The intermediate rendered model with these starting optical property values ​​can then be compared with the actual volume model, and in particular with (one or more) visible light images of the volume model (or used to form the volume model). The volume model may include a camera position (or may assume a camera position) at the time of scanning. This allows the system to generate an estimated image from the intermediate rendered model ("estimated image") that can be directly compared to an image captured by the scanner ("real image"). By iteratively adjusting the starting optical property values ​​until the estimated image converges to a value within an acceptable range within the real image, the comparison between the real image and the estimated image can be quantified, and the difference between the real image and the estimated image can be minimized. The acceptable range can be predetermined, or can be determined based on the rate of change of the difference. Any suitable iterative minimization protocol can be used. Any suitable iterative minimization protocol can be used. For example, a nonlinear minimization technique can be used.

[0075] In this first example, the methods, systems and / or computer readable media described herein can assume that the prior value is a constant. The prior value can be used not only to represent the optical properties of the outer surface, but also to represent the thickness of the enamel between the outer surface and the dentin. The methods, systems and / or computer readable media described herein benefit from the use of an intraoral scanner that can determine the shape (external features, including external enamel) and thickness of the enamel of the tooth and the location and distribution of the dentin within the tooth.

[0076] Initial parameters may preferably be adjusted on certain areas, including on the outer surface and / or within the enamel, or within areas of the enamel. In some variations, optical properties (e.g., one or more or two or more of light absorption, light reflection, light transmission, and light scattering) may be set based on guesses from the visible light portion of the initial volume model. In some variations, the system, in particular the parameter value setting engine portion of the system, may be configured as an agent that is capable of performing machine learning based on volume models from multiple patients to set initial values ​​for optical properties.

[0077] Once the iterative minimization has sufficiently converged to values ​​of one or more (e.g., two or more) optical properties for the voxels that constitute the external tooth surface and the region between the external tooth surface and dentin, these optical properties can be added to all or part of the original volume model to form a visible light volume model.

[0078] In use, a visible light volume model can be used to generate a dental restoration. The visible light volume model can provide a more realistic model of the optical appearance of the patient's (single or multiple) teeth. The more realistic visible light volume model can then be applied automatically or manually to form a dental implant. The model can be used to replace or repair teeth. In some examples, the original volume model can be formed by scanning the tooth to be replaced or repaired to determine the position (and shape) of the dentin in the tooth relative to the surface (e.g., the thickness of the enamel), so the method described above can be used to form a more accurate visible light volume model of the tooth, which includes the dentin position in the tooth. If the patient's mouth lacks a target tooth to be reshaped and / or replaced, one or more teeth adjacent to the target tooth can be scanned, or more preferably, if there are complementary teeth on the opposite side of the jaw, the complementary teeth on the opposite side of the jaw can be scanned (e.g., if the upper right canine is replaced, the upper left canine can be scanned). Therefore, it is assumed that the restored tooth has similar optical properties to the remaining teeth.

[0079] The dental restoration may be formed from a visible light volume model that includes one or more optical properties within some or all of the voxels that describe the external and internal structure of the tooth. For example, the optical properties of materials representing dentin and / or enamel may be manually or automatically applied to or in the dental restoration as it is formed to mimic more natural-looking optical properties. The teeth may be manually or, more preferably, automatically manufactured using a 3D printer or other additive manufacturing technology.

[0080] In addition to information about the shape and extension of the dentin and the thickness of the enamel, the model of the target tooth can also incorporate a more realistic representation of the optical properties of the patient's dentin and enamel. For example, a target tooth or a region of a target tooth can be modeled (and / or manufactured) using a volume model of the target tooth or a similar tooth that describes the relative dentin position within the tooth, as well as prior information about the optical properties of the dentin and enamel. Prior information on dentin and enamel can include values ​​for the average color of dentin (and in some variations, scattering and absorption) and values ​​for enamel absorption and scattering. These values ​​can be for each wavelength. Prior values ​​can be assumed values ​​and can be based on average values ​​or population values.

[0081] Using prior values ​​about teeth as well as volumetric information, the systems and methods described herein can determine estimates of the optical properties of teeth, since teeth can appear at any point and angle (actual image data).

[0082] The optical properties of a tooth can depend in part on the volumetric properties of the tooth when viewed from a position outside the tooth. For example, as light passes through different layers (e.g., enamel and dentin), light scattering and absorption at different illumination wavelengths and the surface properties of the tooth may change. Therefore, the appearance of the tooth is built on different layers. A volume model of a tooth acquired using a penetrating wavelength (e.g., near-infrared light) can provide a three-dimensional volumetric data set of the tooth, and the model can be used to estimate the effects of these different layers on the optical properties of the tooth. For example, for a specific wavelength, the color Y of a tooth from a specific location (e.g., from outside the tooth, at a given point and angle relative to the tooth) can be estimated as the difference between the product of the enamel contribution and the dentin contribution and the length from that point (e.g., from the outer surface) to the dentin.

[0083] As described above, the estimate of the optical properties per wavelength can be compared to the actual optical properties seen or measured from outside the tooth. For example, a scanner (e.g., in some variations, the same scanner determines a volume model of the tooth) can record RGB information of the tooth from outside the tooth, and this measurement at a particular point and angle X can be compared to the calculated value Y. The difference between X and Y per wavelength can provide a value (e.g., a "reinterpreted X value" or error) that can be minimized when forming a tooth model. For example, a priori values ​​of average optical properties of dentin (e.g., scattering and absorption) and a priori values ​​of optical properties of enamel (e.g., absorption and scattering) can be modified to minimize the reinterpreted X value over a range of (visible) wavelengths.

[0084] In practice, the materials used to form enamel and dentin in the model may be limited to a limited number of materials with optical properties such as average light scattering (light reflection) and light absorption. To determine which materials are used to model enamel and dentin, the optical properties of the available materials may be used as prior values ​​used to calculate the optical property Y at different wavelengths, and the resulting material that best fits the observed color (e.g., the smallest reinterpreted X value) may be used to model the tooth or tooth portion. Thus, by setting the prior values ​​to values ​​obtained from the available materials, the material that provides the best fit may be determined.

[0085] Optionally, prior values ​​for optical properties of enamel and / or dentin can be estimated based on one or more patient- or tooth-specific properties. For example, prior values ​​for enamel and / or dentin can be estimated based on one or more properties (e.g., known properties such as the patient's age), or based on an estimate of the patient's age based on jaw shape, tooth structure, or other internal structure, or from measured properties of the teeth (e.g., near-infrared transparency, absorption, or scattering of the teeth). These additional properties can be used to refine the estimate of enamel and / or dentin so that it can be specifically calibrated for the patient. For example, the system can be trained to calibrate between known parameters of dentin and / or enamel and optical properties (e.g., prior values ​​that can be used).

[0086] Optionally, in addition to using a priori values ​​for the optical properties of the tooth in order to model the tooth (or region of the tooth) to generate a visible light volume model, the tooth can be scanned to determine the geometric distribution of dentin and enamel within the tooth volume (e.g., using a near infrared wavelength or wavelength range), as well as using one or more visible light wavelengths that are partially absorbed and scattered by the enamel. The near infrared wavelength scan information can be combined, and estimates of the volume transparency and scattering and / or absorption of the tooth at specific visible light wavelengths can be derived from these additional (e.g., RGB) visible light wavelength scans, and an accurate approximation of the internal structure can be provided. Although these additional (e.g., RGB) wavelengths are less penetrating, due to the poorer transparency of enamel at these wavelengths, it may be difficult to obtain the volume distribution of internal structure (e.g., dentin) within the tooth using only this information. However, if this information is combined with the volume information from the more penetrating near infrared information, thereby providing the precise location of the internal structure, then the transparency and absorption at each visible light wavelength can be approximated by modifying the same process that would otherwise be used to discover the internal structure.

[0087] For example, volume information can be determined from a tooth by scanning from multiple different locations around the tooth using near-infrared wavelengths. The scan provides both the location of the scanner (e.g., the location of emitted / received near-infrared light) and an image taken through the tooth at that location. Assuming that enamel has a high degree of transparency to near-infrared light, while other internal structures (such as dentin, caries, etc.) have a low degree of transparency, this data can be used to reconstruct the internal volume. When the tooth is scanned using visible light (enamel is not transparent to visible light but may instead be absorbing and / or scattering), parameters for transparency and / or absorption / scattering can be set as variables, where the internal structure can be known from the near-infrared imaging. Therefore, in some variations, the visible light volume model can be determined more directly from the initial volume model to include optical properties such as transparency and / or absorption / scattering generated at multiple visible light wavelengths.

[0088] For example, a technique called volume backpropagation can be used. Volume backpropagation can be used to estimate (e.g., track) rays of the sensing wavelength that pass through the tooth volume and enter the camera. The actual intensity reaching the sensor for each ray can be determined by the penetration image and the position and orientation of the sensor (camera). For each ray, the intensity attenuation caused by scattering in the volume through which it passes can be estimated. For example, when using near-infrared light, the transmission of light through strongly scattering and weakly absorbing materials can be modeled by a technique (e.g., Monte Carlo method, etc.) using a hybrid computational scheme of scattering to obtain the spatial variation of the transmittance of light through the material. A set of projection data can be estimated by spatially extrapolating the difference in optical density between the absorbing object and the non-absorbing reference for the shortest flight time. Therefore, this technique may produce differences in absorption coefficients. For example, see E. Wolf, "Three-dimensional structure determination of semi-transparent objects from holographic data", Optics Communications, 1(4), pp. 153-156 (1969). The volume scattering can then be estimated by solving for the actual intensity reaching the sensor.

[0089] Given a volumetric structure model from NIR data, another wavelength (e.g., from the visible spectrum) can be used to solve for one or more optical properties, such as transparency. This can be done, for example, using the volumetric model from the NIR directly, or by modifying the volumetric model using a predetermined method (e.g., specifying some previously measured function / mapping from NIR transparency to R / G / B transparency).

[0090] In any of these methods, when solving for the optical properties of visible light of different frequencies within the tooth volume (e.g., light transparency and / or light absorption / light scattering), some assumptions may be made to simplify the procedure. For example, the method may assume that the enamel on the tooth has uniform optical properties (e.g., transparency, absorption, and scattering, etc.). Therefore, any estimates of the optical properties can be consistently applied to the modeled teeth or tooth regions. Optionally, the method may assume that a single tooth (or group of teeth) has similar or identical optical properties. Therefore, when more than one tooth or group of teeth is modeled, the method may model these different groups of teeth separately to determine the optical properties of the different teeth or groups of teeth in the model. Finally, the method may assume that the optical properties of each point or subvolume (e.g., voxel) within the enamel can have different values ​​at a certain resolution; therefore, the method can calculate maps or models of these optical properties, which can correspond to volume models (e.g., models generated by near-infrared imaging).

[0091] As mentioned above, the volume model obtained from the near infrared wavelengths and the optical properties (which form a combined visible light volume optical model) can be used to construct a model of a tooth or a portion of a tooth (or multiple teeth) having optical properties similar to or identical to the optical properties of the patient's natural teeth. This information can be used to generate a more precise digital model of the (single or multiple) teeth and / or a more accurate physical model, such as a restorative implant. For example, a restorative implant can be manufactured by 3D modeling using materials corresponding to the identified optical properties and volume structure.

[0092] Although the above exemplary methods generally use volume information obtained from near infrared scanning and modeling to determine internal structure (e.g., the area between dentin and enamel in addition to visible light (e.g., RGB) wavelengths, any of these methods may alternatively or additionally be used with visible light wavelengths, particularly red (e.g., wavelengths in the range of about 650 nm, such as between 600-750 nm, between 600-740 nm, between 600-730 nm, between 600-720 nm, between 600-710 nm, and between 600-700 nm, etc.). In some variations, both near infrared wavelengths and visible light wavelengths may be used to determine a volume model of the tooth (or multiple volume models that may be combined), and additional optical properties may be used to determine the color and / or transparency of the tooth.

[0093] For example, in one example, volume data derived from visible wavelengths (such as red) can be used to determine the relative position of dentin in a replaced or simulated tooth, and the optical properties of the simulated tooth or tooth portion can be estimated. Internal structures can be formed in a model (e.g., as part of a restorative implant and / or a digital model), and enamel with an estimated or matched color can be used.

[0094] In another example, volume data derived from visible wavelengths (e.g., red) can be used to determine the relative position of dentin in a tooth, and prior information about the optical properties of dentin and enamel can be used (e.g., such as values ​​for average color, scattering, and absorption for dentin, and values ​​for absorption and scattering for enamel). This information can then be used to generate a model, such as a restorative implant for a tooth as described above.

[0095] Also described herein is a method in which optical properties of a tooth or tooth region (e.g., light absorption, light transmission, light reflection, and light emission, etc.) can be determined by directly scanning with wavelengths of light within the visible light spectrum alone, and a volume estimate for each wavelength can be generated for each wavelength. This information can provide each color component individually, and the resulting information can be used to determine the contribution of each color component at depth within the volume. In this example, volume reconstruction using each different wavelength (e.g., red, blue, and green wavelengths) can provide an estimate of the contribution of each of these wavelengths to the final optical properties to be modeled. For example, although blue wavelengths of light typically penetrate teeth very low, and therefore the penetration depth of the volume information may be quite low, this information can be combined with volume models of other visible wavelengths to provide a model of the visible properties of the tooth.

[0096] For example, volume back propagation or any other appropriate method can be used to estimate a volume model using each visible light wavelength. The scanner can provide position information for the emission / sensing of the visible light wavelength relative to the tooth, as well as multiple different images taken with each wavelength from known positions. This combination of information can then be used to solve for volume information within the scanned tooth.

[0097] A combined model that incorporates volume reconstructions of each visible (e.g., RGB) wavelength can be used to form a more accurate digital model, which in turn can be used to generate a physical model, such as a prosthetic implant. For example, a 3D printer that allows specification of the RGB components of each voxel can receive this information for each voxel within the reconstruction volume.

[0098] Example

[0099] The methods, systems, and / or computer-readable media described herein can be used with or include a scanner, such as an intraoral scanner, that scans under illumination with near infrared (penetrating) light and visible light (e.g., white light, at about 400-600 nm). For example, Figure 3A and 3B Such an intraoral scanner is shown. In addition to using penetrating wavelengths such as near infrared illumination (e.g., 850 nm), the use of visible light can also allow optical properties in addition to volume properties to be determined. The visible light volume model can include and associate two types of information (e.g., internal and external structural information and optical properties) that can generate a more accurate mapping of (single or multiple) teeth, which can be used, for example, in the process of making a dental restoration to more accurately identify (and later match) the color, transparency, and coloring of the teeth. The visible light volume model can be used with one or more technologies (e.g., 3D printing) to repair or generate the entire 3D structure of all or part of the original tooth with matching optical properties, thereby obtaining a better simulation of the tooth for a dental restoration (e.g., crowns and implants). The original volume model can be generated as described herein using, for example, near infrared and / or transmitted illumination scanning combined with a 3D scan of the tooth surface.

[0100] Methods and apparatus described herein may include intraoral scanners and methods of using such scanners for generating a three-dimensional (3D) model of an intraoral region of a subject (e.g., single or multiple teeth, gums, jaws, etc.), which may include internal features of the teeth and may also include models of the surfaces. For example, Figure 3A An example of an intraoral scanner 301 that may be configured or adapted to generate a 3D model having both surface and internal features as described herein is shown. Figure 3B As shown in Figure 1, an exemplary intraoral scanner may include a wand 303 that may be held by an operator (e.g., a dentist, dental hygienist, technician, etc.) and moved over a subject's (single or multiple) teeth to scan both the surface and the internal structure. The wand may include one or more sensors 305 (e.g., cameras such as CMOS, CCD, and detectors, etc.) and one or more light sources 309, 310, 311. Figure 3BIn FIG. 1 , three light sources are shown: a first light source 309 configured to emit light in a first spectral range for detecting surface features (e.g., visible light, monochromatic visible light, etc.; the light does not have to be visible light); a second color light source (e.g., white light in a wavelength range between 400-700 nm, such as approximately between 400-600 nm); and a third light source 311 configured to emit light in a second spectral range for detecting internal features within a tooth (e.g., by transillumination, small-angle penetration imaging, laser fluorescence, etc., which may generally be referred to as penetration imaging, such as in the near infrared). Although in Figure 3B A separate illumination source is shown in FIG. 3 , but in some variations, an alternative light source may be used. The light source may be any suitable light source, including LEDs, fiber optics, etc. The wand 303 may include one or more controls (buttons, switches, dials, touch screens, etc.) to assist in control (e.g., turning the wand on / off, etc.); and optionally or additionally, one or more controls not shown may be present on other parts of the intraoral scanner, such as a foot pedal, keyboard, console, touch screen, etc.

[0101] In general, any suitable light source may be used, particularly a light source that matches the pattern being detected. For example, any of these devices may include a visible light source or other (including invisible) light source for surface detection (e.g., at a wavelength of 680 nm or about 680 nm, or other suitable wavelength). A color light source, typically a visible light source (e.g., a "white light" light source), may also be included for color imaging. In addition, a penetrating light source (e.g., infrared, such as, in particular, a near-infrared light source) may also be included for penetrating imaging.

[0102] The intraoral scanner 301 may also include one or more processors, including linked processors or remote processors, for controlling the operation of the wand 303, including coordinating the scanning and reviewing and processing the scanning and generation of a 3D model including surface and internal features. Figure 3B As shown, one or more processors 313 may include a memory 315, or may be coupled to a memory 315, which is used to store scan data (surface data, internal feature data, etc.). Communication circuits 317 (including wireless communication circuits or wired communication circuits) may also be included, which are used to communicate with components of the system (including sticks) or external components including external processors. For example, the system can be configured to send and receive scans or 3D models. One or more additional outputs 319 for outputting or presenting information may also be included, and the additional outputs 319 may include display screens, printers, etc. As described above, inputs 321 (buttons, touch screens, etc.) may be included, and the device may allow or request user input for controlling scanning and other operations.

[0103] Any of the devices and methods described herein can be used to scan and / or identify internal structures in enamel and / or dentin, such as cracks, caries (cavities), and damage. Therefore, any of the devices described herein can be configured to perform a scan that can be used to detect internal structures using a penetration wavelength or a spectral range of a penetration wavelength. Also described herein are methods for detecting cracks, caries, and / or damage or other internal features (e.g., tooth fillings, etc.). A variety of penetration scanning techniques (penetration imaging) can be used or incorporated into a device, including but not limited to transillumination and small-angle penetration imaging, both of which detect the passage of light of a penetration wavelength from or through tissue (e.g., from or through a single or multiple teeth).

[0104] Figure 3C A schematic diagram of an intraoral scanner configured to perform surface scanning (e.g., non-penetrating scanning using visible light) and penetrating scanning using near infrared (IR) wavelengths is shown. Figure 3C In an intraoral scanner, the scanner includes a polarizer (e.g., linear polarizer 281) and a filter 283 to block near-infrared light reflected from the tooth surface while still collecting near-infrared light reflected from internal structures. In this example, near-infrared light is applied with a known polarization (P) (850nm in this example); the emitted light illuminates the tooth, and specular light reflected from the tooth surface (e.g., enamel) is reflected while maintaining the specular polarization state. In contrast, light impinging on internal features such as dentin may be scattered, which can change the polarization state. Within the intraoral scanner, light returning through the rod to a sensor (e.g., a CMOS detector) is first filtered through a filter 283, which transmits scattered (S) light from internal structures to the detector, but does not pass specular light with the original polarization (P) to the detector. Other intraoral scanner configurations (e.g., Figure 3C those shown) can be used as part of the probe.

[0105] The methods, systems and / or computer readable media described herein can provide more detailed visual characteristics of teeth, and can also or alternatively allow automatic and / or more accurate 3D restoration of the internal structure of teeth. These benefits can make the restoration closer to the original tooth, while being more robust to light conditions, lighting angles, viewing angles, backgrounds, spectra, and other factors that affect the appearance of dental implants (including restorations such as artificial teeth, crowns, dentures, dental veneers, bridges, etc.).

[0106] Reconstruction of the internal and surface features of teeth (e.g., using segmentation of internal regions such as dentin and enamel thickness) can be used as restorative laboratory data to generate a 3D reconstruction of a single tooth, multiple teeth, or a portion of a single or multiple teeth. Thus, a model of a patient's teeth including internal structure (e.g., a volume model or data representing a volume model) can be converted into restorative laboratory data, which will allow for more accurate manual formation of implants (e.g., artificial teeth, crowns, dentures, and dental veneers, etc.) or automatic formation of implants (e.g., by 3D printing or robotic formation). The use of these volume models can facilitate the formation of implants that replicate or mimic the internal structure, transparency, and color (hue and intensity, etc.) of the teeth that are part of the implant, and thereby best resemble the patient's real teeth.

[0107] In any of the methods and devices described herein for modeling surfaces and internal structures, the device (e.g., scanner) can be configured to simultaneously record color (e.g., visible light, RGB, etc.) data from the teeth, and this color information can be included as part of the volume model data (e.g., 3D reconstruction). These volume models can be adapted to form visible light volume models by including volume visible light information.

[0108] Examples of intraoral scanners and methods of operating them to generate volume models are provided below. Penetrating images (e.g., images taken using a near-infrared intraoral scanner) can generate a volume model of the teeth. Based on the more accurate tooth structure and optical properties provided by the visible light volume model engine, the volume model can be modified to include optical property information as described herein and can be used to construct a dental prosthesis device. See, for example, the following description of the Figure 4B . Although the methods and apparatus described herein are provided in the context of using near infrared or infrared light to determine internal structure, any of these methods and apparatus and particularly methods for modeling and constructing more accurate dental implants can be combined with or used in conjunction with other imaging techniques that provide internal structure of teeth, including, for example, X-ray or CBCT imaging.

[0109] When near infrared is used, a volume model can be formed from near infrared or infrared images collected by an intraoral scanner (or any other wavelength that can penetrate the tooth surface, such as 800nm, 850nm, 900nm, etc.). The volume model can include a 3D density map of the internal tooth structure, a 3D map of the optical properties of the outer surface and / or the area between the outer surface and dentin, dentin, etc. (e.g., for each point or voxel inside the tooth model), and optionally a segmentation of different structures (e.g., dentin, enamel, and / or the surfaces separating them).

[0110] Any intraoral scanner described herein can be configured to capture three or more of the above-mentioned imaging modes in real time: for example, surface 3D scanning, RGB color capture of the tooth surface, and near-infrared or infrared images that can penetrate the tooth surface and the image structure inside the tooth. This information (and especially the penetrating images) can be used to generate a volume map of the tooth. The ability to capture at least these three imaging modes simultaneously or nearly simultaneously (for example, by quickly scanning between them) can allow the generation of a three-dimensional model of (single or multiple) teeth, which can be modified to include optical properties such as light absorption, light reflection, light transmission and / or light emission. Therefore, this information can be used to produce precise dental implants, including tooth replacements or restorations, such as crowns, dental veneers, dentures, bridges, etc.

[0111] In restorative treatment, a restorative implant (e.g., a crown or bridge) can use the information used to color and glaze the implant. The methods, systems, and / or computer-readable media described herein can generate one or more models of the internal and external structure and 3D optical properties of a tooth for at least the outer surface and the area between the outer surface and the dentin.

[0112] Figure 4A An example of a process flow for a method for forming a denture (e.g., a dental restoration) 2701 such as the one currently being processed is shown. These steps may include taking measurements of the patient's teeth, including the teeth to be corrected and the patient's other teeth 2703. These measurements may be taken manually (e.g., using a cast of the teeth) and / or using a digital scanner (e.g., an intraoral scanner). These methods may also generate a visible light volume model 2705 from the initial volume model. After iterative processing of the optical properties as described above, the resulting optical property match may be based on an overall impression of the teeth. Depending on how the optical properties were initially set / assigned, their spatial distribution may be very limited. All of this information may be sent to a laboratory 2709 to manufacture an implant 2711, which may then be checked for fit 2713 (and modified if not) and mounted on the patient 2715.

[0113] Intraoral scanners may be used to provide surface measurements of a patient's teeth and may be adapted to provide optical properties for voxels within a volume.

[0114] The optical properties within the volume can be related to the thickness of the enamel, which can be easily estimated when the three-dimensional distribution of the outer surface and dentin is known. Therefore, the optical property information can be combined with the shape and / or visible light information from the original volume model of the tooth. Figure 4BAs described, a restorative implant 2701 may be prepared using an intraoral scanner 2726, which may provide both a volumetric map and optical properties of the scanned tooth, including data of 3D dimensions; this information may be used directly (digitally) to form the implant, or it may be sent to a laboratory to form the implant from the data 2729. The implant may then be checked for fit 2713 (and modified if not), and mounted on the patient 2715.

[0115] Using near infrared and / or infrared data to enhance the volumetric data of the scanned tooth allows for the association of optical properties within the volumetric model (or in a separate data structure associated with the volumetric model).

[0116] In practice, a laboratory may receive a request for a 3D measurement as well as information about its optical properties within the volume. An intraoral scanner (IOS) can be configured to automatically acquire the 3D and optical properties of the tooth.

[0117] Any method described herein (including user interface) may be implemented as software, hardware, or firmware, and may be described as a non-transitory computer-readable storage medium storing a set of instructions executable by a processor (e.g., a computer, tablet computer, smartphone, etc.), which, when executed by the processor, causes the processor control to perform any of the following steps, including but not limited to: displaying, communicating with a user, analyzing, modifying parameters (including timing, frequency, and intensity, etc.), determining, and issuing an alarm, etc.

[0118] When a feature or element is referred to as "on" another feature or element in this article, it can be directly located on the other feature or element, and / or there may also be intermediate features and / or elements. On the contrary, when a feature or element is referred to as "directly on" another feature or element, there is no intermediate feature or element. It should also be understood that when a feature or element is referred to as "connected", "attached" or "coupled" to another feature or element, it can be directly connected, attached or coupled to the other feature or element, or there may be intermediate features or elements. On the contrary, when a feature or element is referred to as "directly connected", "directly attached" or "directly coupled" to another feature or element, there is no intermediate feature or element. Although described or shown relative to an embodiment, the features and elements described or shown in this way can be applied to other embodiments. Those skilled in the art will also recognize that the reference to the structure or feature set for "adjacent" another feature can have a part overlapping with adjacent features or located below adjacent features.

[0119] The terms used herein are only used for the purpose of describing specific embodiments and are not intended to limit the present invention. For example, unless the context clearly indicates, as used herein, the singular forms "a", "an", and "the" are intended to include the plural forms as well. It should be further understood that the terms "comprises" and / or "comprising" when used in this specification specify the presence of stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items and may be abbreviated as " / ".

[0120] Spatially related terms such as "under", "below", "lower", "over", and "upper" may be used herein to describe the relationship between an element or feature and another element or feature, or with multiple elements or features as shown in the drawings. It will be understood that spatially related terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the drawings. For example, if the device in the drawings is inverted, the elements described as "under" or "beneath" other elements or features will be oriented to be "over" other elements or features. Therefore, the exemplary term "under" may include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or in other orientations), and the spatially relative descriptors used herein are interpreted accordingly. Similarly, unless otherwise specifically stated, the terms "upwardly", "downwardly", "vertical", "horizontal", etc. are used herein for illustrative purposes only.

[0121] Although the terms "first" and "second" may be used herein to describe various features / elements (including steps), these features / elements should not be limited by these terms unless the context indicates otherwise. These terms may be used to distinguish one feature / element from another feature / element. Therefore, without departing from the teachings of the present invention, the first feature / element discussed below may be referred to as the second feature / element, and similarly, the second feature element discussed below may be referred to as the first feature / element.

[0122] In this specification and the appended claims, unless the context requires otherwise, the word "comprise" and variations such as "comprises" and "comprising" mean that various components (e.g., compositions and devices including apparatus and methods) can be used together in methods and articles. For example, the term "comprising" will be understood to imply the inclusion of any stated elements or steps but not the exclusion of any other elements or steps.

[0123] Generally, any apparatus and method described herein should be understood to be inclusive, but all or a subset of components and / or steps may optionally be exclusive and may be expressed as "consisting of" or "consisting essentially of" the various components, steps, subcomponents or sub-steps.

[0124] As used herein in the specification and claims, including in the examples, unless otherwise expressly stated, all numbers may be understood as if preceded by the word "about" or "approximately", even if the term does not explicitly appear. The phrase "about" or "approximately" may be used when describing an amplitude and / or position to indicate that the value and / or position described is within a reasonably expected range of values ​​and / or positions. For example, a numerical value may have a value of + / -0.1% of the value (or range of values), + / -1% of the value (or range of values), + / -2% of the value (or range of values), + / -5% of the value (or range of values), + / -10% of the value (or range of values), etc. Any numerical value given herein should be understood to include about that value or approximately that value, unless the context indicates otherwise. For example, if the value "10" is disclosed, "about 10" is also disclosed. Any numerical range recited herein is intended to include all subranges contained therein. It should also be understood that when a value is disclosed as "less than or equal to" the value, "greater than or equal to the value" and possible ranges between the values ​​are also disclosed, as appropriately understood by those skilled in the art. For example, if a value "X" is disclosed, "less than or equal to X" and "greater than or equal to X" (e.g., where X is a numerical value) are also disclosed. It should be understood that throughout the application, data is provided in a variety of different formats and that the data represents end points and starting points and ranges for any combination of data points. For example, if a specific data point "10" and a specific data point "15" are disclosed, it should be understood that greater than, greater than or equal to, less than, less than or equal to, and equal to 10 and 15, as well as between 10 and 15 are considered disclosed. It should also be understood that every unit between two specific units is also disclosed. For example, if 10 and 15 are disclosed, 11, 12, 13, and 14 are also disclosed.

[0125] Although various illustrative embodiments are described above, any of several changes may be made to the various embodiments without departing from the scope of the invention as described in the claims. For example, in optional embodiments, the order in which the various described method steps are performed may generally be changed, and in other optional embodiments, one or more method steps may be skipped altogether. Optional features of the various device and system embodiments may be included in some embodiments and not included in other embodiments. Therefore, the foregoing description is provided primarily for exemplary purposes and should not be construed as limiting the scope of the present disclosure as set forth in the claims.

[0126] The examples and descriptions included herein show by way of illustration and not limitation specific embodiments in which the subject matter can be practiced. As mentioned, other embodiments can be utilized and derived therefrom, so that structural and logical replacements and changes can be made without departing from the scope of the present disclosure. For convenience only, the term "invention" may be used herein individually or collectively to refer to these embodiments of the subject matter of the present invention, and it is not intended that the scope of the present application is actively limited to any single invention or inventive concept, if in fact more than one invention or inventive concept is disclosed. Therefore, although specific embodiments have been illustrated and described herein, any arrangement predicted to achieve the same purpose may replace the specific embodiments shown. The present disclosure is intended to cover any and all modifications or variations of various embodiments. By reading the above description, the combination of the above embodiments and other embodiments not specifically described herein will be apparent to those skilled in the art.

Claims

1. A method for making a dental restoration for a patient so that the dental restoration has optical properties that match the optical properties of the patient's teeth, the method comprising: generating or receiving a volumetric model of at least a portion of the patient's teeth from a three-dimensional intraoral scanner operating at both near infrared wavelengths and at least one visible wavelength, wherein the volumetric model includes a representation of an outer surface of the patient's teeth and an enamel region extending from the outer surface of the patient's teeth to the dentin, wherein the volumetric model includes the thickness, shape, and distribution of the enamel and dentin; estimating, based on the volumetric model, values ​​of one or more of: light absorption, light reflection, light transmission, and light scattering for one or more visible wavelengths of light for the patient's teeth and a region of the enamel extending from an outer surface of the patient's teeth to the patient's dentin; adding the estimated values ​​to the volume model to form a visible light volume model; and Information for making a dental restoration is transmitted, wherein the surface and the inner structure of the dental restoration have optical properties based on the visible light volume model.

2. The method according to claim 1, wherein: Generating or receiving the volumetric model includes receiving a volumetric model of at least a portion of the patient's teeth for teeth adjacent to the patient's teeth to be restored by the dental restoration.

3. The method according to claim 1, wherein: Fabricating the dental restoration comprises generating a volume model of the dental restoration comprising a plurality of voxels, wherein voxels of the volume model of the restoration have values ​​based on values ​​of voxels of the visible light volume model.

4. The method according to claim 1, wherein: The estimated values ​​include estimating values ​​of one or more of: light absorption, light reflection, light transmission, and light scattering for each of a plurality of voxels defining an outer surface of the patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin.

5. The method according to claim 1, wherein: The estimated values ​​include estimating values ​​of one or more of: light absorption, light reflection, light transmission, and light scattering at three or more visible light wavelengths for each of a plurality of voxels defining an outer surface of a patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin.

6. The method according to claim 5, wherein: The three or more visible light wavelengths include one or more red wavelengths, green wavelengths, and blue wavelengths.

7. According to the method of claim 1, the estimating includes estimating the values ​​of one or more of the following by setting the values ​​of one or more of the following to predetermined prior values: light absorption, light reflection, light transmission and light scattering at one or more visible light wavelengths for each of a plurality of voxels defining an outer surface of a patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin.

8. The method of claim 1 further comprising setting one or more of the following values ​​to predetermined prior values ​​determined by parameter estimation: light absorption, light reflection, light transmission, and light scattering at one or more visible light wavelengths for each of a plurality of voxels defining an outer surface of a patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin.

9. The method according to claim 1, wherein: The estimation includes iteratively estimating values ​​of one or more of the following: light absorption, light reflection, light transmission, and light scattering at one or more visible light wavelengths for each of a plurality of voxels defining an outer surface of the patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin, based on a reconstructed volume and the position of the camera compared to RGB data recorded when the patient's teeth were scanned using an intraoral scanner to generate the body model, so as to determine a value close to the optical property.

10. The method according to claim 1, wherein: The estimation includes estimating one or more of the following values: light absorption, light reflection, light transmission, and light scattering at one or more visible light wavelengths for each of a plurality of voxels defining an outer surface of a patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin by setting one or more of the following values ​​to predetermined prior values ​​determined from a representative patient population, wherein the prior values ​​are selected using one or more of the following: measured RGB data, volume information, and patient information recorded when scanning the patient's teeth using an intraoral scanner to generate the body model.

11. The method according to claim 10, wherein: The volume information includes the path length from the tooth surface through the enamel to the dentin.

12. The method according to claim 10, wherein: The patient information includes one or more of the following: patient age, gender, estimated jaw shape.

13. The method of claim 1 further comprises dividing the volume model into a plurality of sub-regions prior to estimating values ​​of one or more of: light absorption, light reflection, light transmission, and light scattering for one or more visible light wavelengths for an outer surface of a patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin.

14. A non-transitory computer readable medium storing instructions for execution by a processor to prepare a dental restoration having optical properties that match the optical properties of a patient's teeth, wherein: When the instructions are executed, the processor: generating or receiving a volumetric model of at least a portion of the patient's teeth from a three-dimensional intraoral scanner operating at both near infrared wavelengths and at least one visible wavelength, wherein the volumetric model includes a representation of an outer surface of the patient's teeth and an enamel region extending from the outer surface of the patient's teeth to the dentin; wherein the volume model includes the thickness, shape and distribution of enamel and dentin; estimating, based on the volumetric model, values ​​of one or more of: light absorption, light reflection, light transmission, and light scattering for one or more visible wavelengths of light for the patient's teeth and a region of the enamel extending from an outer surface of the patient's teeth to the patient's dentin; adding the estimated values ​​to the volume model to form a visible light volume model; and Information for manufacturing a dental restoration is transmitted, wherein the surface and the inner structure of the dental restoration have optical properties based on the visible light volume model.

15. The non-transitory computer readable medium of claim 14, wherein: The instructions cause the processor to receive a volumetric model of at least a portion of the patient's tooth, wherein the volumetric model includes a plurality of voxels defining an outer surface of the patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin.

16. The non-transitory computer readable medium of claim 14, wherein: The instructions cause the processor to estimate values ​​of two or more of: light absorption, light reflection, light transmission, and light scattering for each of a plurality of voxels defining an outer surface of a patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin.

17. The non-transitory computer readable medium of claim 14, wherein: The instructions cause the processor to estimate values ​​of one or more of: light absorption, light reflection, light transmission, and light scattering at three or more visible light wavelengths for each of a plurality of voxels defining an outer surface of a patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin.

18. The non-transitory computer readable medium of claim 17, wherein: The three or more visible light wavelengths include one or more red wavelengths, green wavelengths, and blue wavelengths.

19. The non-transitory computer readable medium of claim 14, wherein: The instructions cause the processor to estimate values ​​of one or more of: light absorption, light reflection, light transmission, and light scattering for one or more visible light wavelengths for each of a plurality of voxels defining an outer surface of a patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin by setting one or more of the following values ​​to predetermined prior values.

20. The non-transitory computer readable medium of claim 14, wherein: The instructions cause the processor to set values ​​of one or more of the following to predetermined prior values ​​determined by parameter estimation: light absorption, light reflection, light transmission, and light scattering for one or more visible light wavelengths for each of a plurality of voxels defining an outer surface of a patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin.

21. The non-transitory computer readable medium of claim 14, wherein: The instructions cause the processor to iteratively estimate values ​​of one or more of the following: light absorption, light reflection, light transmission, and light scattering at one or more visible light wavelengths for each of a plurality of voxels defining an outer surface of the patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin, by based on a reconstructed volume and the position of the camera compared to RGB data recorded when the patient's teeth were scanned using an intraoral scanner to generate the body model, so as to determine a value close to the optical property.

22. The non-transitory computer readable medium of claim 14, wherein: The instructions cause the processor to estimate one or more of the following values: light absorption, light reflection, light transmission, and light scattering at one or more visible light wavelengths for each of a plurality of voxels defining an outer surface of a patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin by setting one or more of the following values ​​to predetermined prior values ​​determined from a representative patient population, wherein the prior values ​​are selected using one or more of the following: measured RGB data, volume information, and patient information recorded when scanning the patient's teeth using an intraoral scanner to generate the body model.

23. The non-transitory computer readable medium of claim 22, wherein: The volume information includes the path length from the tooth surface through the enamel to the dentin.

24. The non-transitory computer readable medium of claim 22, wherein: The patient information includes one or more of the following: patient age, gender, estimated jaw shape.

25. The non-transitory computer readable medium of claim 14, wherein: The instructions cause the processor to divide the volume model into a plurality of sub-regions prior to estimating values ​​for one or more of: light absorption, light reflection, light transmission, and light scattering for one or more visible light wavelengths for an outer surface of a patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin.

26. A non-transitory computer readable medium storing instructions for execution by a processor, which when executed cause the processor to: generating or receiving a volumetric model of at least a portion of a patient's teeth from a three-dimensional intraoral scanner operating at both near infrared wavelengths and at least one visible wavelength, wherein the volumetric model includes a representation of an outer surface of the patient's teeth and an enamel region extending from the outer surface of the patient's teeth to the patient's dentin, wherein the volumetric model includes thickness, shape, and distribution of the enamel and dentin; estimating, based on the volumetric model, values ​​of one or more of: light absorption, light reflection, light transmission, and light scattering for one or more visible wavelengths of light for the patient's teeth and a region of the enamel extending from an outer surface of the patient's teeth to the patient's dentin; adding the estimated values ​​to the volume model to form a visible light volume model; and Information for making a dental restoration is transmitted, wherein the surface and the inner structure of the dental restoration have optical properties based on the visible light volume model.

27. The non-transitory computer readable medium of claim 26, wherein: The instructions cause the processor to receive the volume model from a three-dimensional oral scanner operating at both near infrared wavelengths and visible light wavelengths.

28. The non-transitory computer readable medium of claim 26, wherein: The instructions cause the processor to receive a volumetric model of at least a portion of the patient's tooth, wherein the volumetric model includes a plurality of voxels defining an outer surface of the patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin.

29. The non-transitory computer readable medium of claim 26, wherein: The instructions cause the processor to estimate values ​​for two or more of: light absorption, light reflection, light transmission, and light scattering.

30. The non-transitory computer readable medium of claim 26, wherein: The instructions cause the processor to estimate values ​​of one or more of: light absorption, light reflection, light transmission, and light scattering at three or more visible light wavelengths.

31. The non-transitory computer readable medium of claim 30, wherein: The three or more visible light wavelengths include one or more red wavelengths, green wavelengths, and blue wavelengths.

32. The non-transitory computer readable medium of claim 26, which when executed further causes the processor to fabricate a dental restoration based on the visible light volume model.

33. The non-transitory computer readable medium of claim 26, wherein: The instructions cause the processor to estimate one or more of the following values ​​by setting one or more of the following values ​​to predetermined prior values: light absorption, light reflection, light transmission, and light scattering for one or more visible light wavelengths for the outer surface of the patient's teeth and the enamel region extending from the outer surface of the patient's teeth to the patient's dentin.

34. The non-transitory computer readable medium of claim 26, wherein: The instructions cause the processor to set values ​​for one or more of the following to predetermined prior values ​​determined by parameter estimation: light absorption, light reflection, light transmission, and light scattering for one or more visible light wavelengths for an outer surface of a patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin.

35. The non-transitory computer readable medium of claim 26, wherein: The instructions cause the processor to iteratively estimate values ​​of one or more of: light absorption, light reflection, light transmission, and light scattering for one or more visible light wavelengths for an outer surface of the patient's teeth and an enamel region extending from the outer surface of the patient's teeth to the patient's dentin by iterating based on a reconstructed volume and the position of the camera compared to RGB data recorded when the patient's teeth were scanned using an intraoral scanner to generate the body model, so as to determine a value close to an optical property.

36. The non-transitory computer readable medium of claim 26, wherein: The instructions cause the processor to estimate one or more of the following values ​​by setting one or more of the following values ​​to predetermined prior values ​​determined from a representative patient population: light absorption, light reflection, light transmission, and light scattering for one or more visible light wavelengths for the outer surface of the patient's teeth and the enamel region extending from the outer surface of the patient's teeth to the patient's dentin; wherein the prior values ​​are selected using one or more of the following: measured RGB data, volume information, and patient information recorded when scanning the patient's teeth using an intraoral scanner to generate the body model.

37. The non-transitory computer readable medium of claim 36, wherein: The volume information includes the path length from the tooth surface through the enamel to the dentin.

38. The non-transitory computer readable medium of claim 36, wherein: The patient information includes one or more of: patient age, gender, and estimated jaw shape.

39. The non-transitory computer readable medium of claim 26, wherein: The instructions cause the processor to divide the volume model into a plurality of sub-regions prior to estimating values ​​for one or more of: light absorption, light reflection, light transmission, and light scattering for one or more visible light wavelengths for an outer surface of a patient's tooth and an enamel region extending from the outer surface of the patient's tooth to the patient's dentin.

Images