Occlusion contact quantitative analysis method and system for three-dimensional dentition scanning data and storage medium

Abstract

The invention discloses an occlusion contact quantitative analysis method and system for three-dimensional dentition scanning data and a storage medium, and relates to the field of oral medicine. The method comprises the following steps: acquiring upper and lower jaw dentition triangular mesh curved surface data by utilizing three-dimensional optical scanning; the method comprises the following steps: copying data of triangular mesh curved surfaces of dentitions of upper and lower jaws, independently cutting each tooth, and enabling the cut data to comprise a complete occlusal surface of the tooth; judging whether each triangular mesh on the grid curved surface of each cut tooth is an occlusion contact surface or not; and the size of the occlusal force is calculated according to the occlusal contact surface and the pressure intensity in the occlusal state. According to the invention, accurate quantitative analysis of the occlusal force and direction of each tooth can be realized, the cost is low, and the operation is simple and convenient.

Description

Technical Field

[0001] The present invention relates to the field of stomatology, and more particularly to a method, system and storage medium for quantitative analysis of occlusal contact of three-dimensional dentition scanning data. Background Art

[0002] The detection and analysis of tooth occlusal contact conditions is of great significance for diagnosing whether natural teeth or dentures / restorations are under abnormal stress. At present, related technologies have obvious shortcomings: First, articulating paper technology can only display imprints, and the position and size of the contact points must be judged by the human eye, making it difficult to quantitatively calculate the contact area; although some studies have measured the contact area by taking photos or scanning, they only process it as a two-dimensional plane image and cannot analyze the three-dimensional vector direction of the occlusal force, which is not conducive to the accurate analysis of the force on the teeth. The force direction of the teeth is crucial to periodontal health. For example, teeth can withstand large vertical forces but cannot withstand large lateral forces. If teeth are subjected to large mesiodistal forces, it may cause the separation of two adjacent teeth during occlusion, resulting in food impaction. In addition, this technology is also affected by factors such as saliva, and the color rendering accuracy is not high. It is impossible to calculate the angular relationship between the vector direction of the occlusal force and the long axis of the tooth or the occlusal plane, making it difficult to assess the harm of non-physiological loads such as lateral forces. Secondly, the bite force analyzer represented by T-scan places a piezoelectric film between the upper and lower teeth, asks the patient to bite, and uses a sensor to obtain the size of the tooth bite force. However, this technology is relatively expensive, and the occlusal contact surface is also two-dimensionally planarized, making it impossible to analyze the three-dimensional direction of the bite force and its angular relationship with the normal of the occlusal plane or the long axis of the tooth. At the same time, the piezoelectric film needs to be placed in the patient's mouth, which will interfere with the natural bite state and reduce the comfort level. It is also impossible to directly associate the bite force data with the three-dimensional shape of the teeth (such as the curvature of the occlusal surface and the direction of the long axis of the tooth), making it difficult to guide precise restoration design. Summary of the Invention

[0003] In view of this, the present invention provides a method, system and storage medium for quantitative analysis of occlusal contact of three-dimensional dental scan data, which can realize accurate quantitative analysis of the size and direction of the occlusal force of each tooth with low cost and easy operation.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A method for quantitatively analyzing occlusal contact for three-dimensional dentition scanning data comprises the following steps:

[0006] Use three-dimensional optical scanning to obtain triangulated mesh surface data of the upper and lower jaw dentition;

[0007] Copy the triangulated mesh surface data of the upper and lower jaw dentition and crop each tooth separately. The cropped data includes the complete occlusal surface of the tooth.

[0008] For each triangular mesh on the cut-out mesh surface of each tooth, determine whether it is an occlusal contact surface;

[0009] The bite force is calculated based on the bite contact surface and the pressure under the bite state.

[0010] Optionally, whether it is an occlusal contact surface is determined by setting a distance threshold. If the distance from the triangular mesh to the opposing dentition surface is less than the threshold, it is determined to be an occlusal contact surface.

[0011] Optionally, the distance from the triangular mesh to the opposing dentition surface is calculated by calculating the geometric center point C of the three vertices of the triangular mesh. m , from the geometric center point C m Project onto the opposing dentition surface to obtain the projection point and calculate the Euclidean distance D between the center point and the projection point. m If point C m Above the curved surface of the opposing dentition, D m Take a positive value. If it is below the opposing dentition surface, Dm takes a negative value. The calculation formula for determining whether a triangle mesh m belongs to the occlusal contact surface S is as follows:

[0012] S={m|D m <th,m∈M}。

[0013] Optionally, the specific formula for calculating the bite force is as follows:

[0014]

[0015] in is the bite force on the triangular mesh m, s m is the area of ​​the triangle mesh m, Is a vector whose direction is the triangle mesh unit normal vector In the opposite direction. P is the pressure on the occlusal surface. If P is not measured, the above formula can still calculate the relative occlusal force of each tooth and the direction of the occlusal force.

[0016] A system for quantitative analysis of occlusal contact for three-dimensional dentition scanning data, comprising:

[0017] Triangular mesh surface data acquisition module: used to acquire triangular mesh surface data of upper and lower jaw dentition using three-dimensional optical scanning;

[0018] Complete occlusal surface cropping module: used to copy the triangular mesh surface data of the upper and lower jaw teeth and crop each tooth separately. The cropped data includes the complete occlusal surface of the tooth;

[0019] Occlusal contact surface determination module: used to determine whether each triangular mesh on each cut-out tooth mesh surface is an occlusal contact surface;

[0020] Bite force calculation module: used to calculate the bite force based on the bite contact surface and the pressure under the bite state.

[0021] A computer storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the computer program implements any one of the steps of the method for quantitative analysis of occlusal contact for three-dimensional dentition scanning data.

[0022] As can be seen from the above technical solutions, compared with the prior art, the present invention provides a method, system, and storage medium for quantitative analysis of occlusal contact based on three-dimensional dentition scanning data, which can achieve accurate quantitative analysis of the magnitude and direction of the occlusal force of each tooth, with low cost and simple operation, and has the following beneficial effects:

[0023] 1. Accurately quantify the three-dimensional direction of bite force to improve clinical diagnostic capabilities

[0024] Analyzing harmful lateral forces: Traditional methods can only measure the magnitude or two-dimensional distribution of occlusal force, while this patent can calculate the three-dimensional vector direction of occlusal force (vertical, buccal-lingual, and mesio-distal), thereby identifying non-physiological lateral forces that may cause periodontal damage, loose teeth, or food impaction.

[0025] Evaluate occlusal stability: By analyzing the angle between the occlusal force and the long axis of the tooth or the normal of the occlusal plane, it is determined whether the force on the teeth is reasonable, so as to avoid tooth displacement or temporomandibular joint disorder (TMD) caused by abnormal occlusion.

[0026] Early screening of occlusal abnormalities: Combined with the bite force database of healthy people, patients' occlusal abnormalities (such as unilateral chewing, early contact, interference points) can be quickly screened to improve the accuracy of early intervention.

[0027] 2. Optimize restoration design and improve the bionics of occlusal reconstruction

[0028] Guiding the adjustment of restoration morphology: During implant, crown and bridge or orthodontic treatment, the occlusal surface morphology of the restoration can be optimized based on three-dimensional occlusal force analysis, so that the force direction is closer to the physiological state of natural teeth, reducing the risk of restoration fracture or abutment tooth damage.

[0029] Improve occlusal balance: The occlusal force distribution ratio of each tooth in the entire dentition can be quantified to ensure the left-right symmetry and front-back balance of the occlusal force after restoration, and avoid occlusal disorders caused by excessively high restorations or poor morphology.

[0030] Reduce clinical adjustment time: Traditional restorations need to be repeatedly adjusted after being put in, but this patent can generate highly bionic occlusal contacts during the digital design stage, reducing the number of adjustments during clinical trial fitting.

[0031] 3. Enhance the value of scientific research and teaching, and promote research on occlusal biomechanics

[0032] Establish a healthy occlusion database: By collecting occlusal data from a large number of healthy people, a standard reference range for the size, direction, and distribution of occlusal force is established to provide an objective basis for clinical diagnosis.

[0033] Promote personalized occlusal treatment: Combined with artificial intelligence (AI) analysis, personalized occlusal treatment plans can be developed, such as orthodontic force system optimization and implant occlusal design.

[0034] Promote occlusal biomechanics research: This method can be applied to studies such as temporomandibular joint (TMJ) force analysis and periodontal ligament stress distribution simulation, deepening the understanding of occlusal-periodontal-joint interactions.

[0035] 4. Improve clinical efficiency, reduce costs and invasiveness

[0036] No additional equipment required: Only conventional oral scans or model scan data are required, without the need for additional consumables or sensors such as articulating paper and T-scan, thus reducing clinical costs.

[0037] Non-invasive analysis: Traditional bite force meters require a thin film to be placed in the mouth, which may interfere with natural occlusion. However, this patent is based on existing scanning data and does not affect the patient's occlusal status.

[0038] Digital workflow integration: It can be seamlessly connected with existing CAD / CAM restoration systems and orthodontic software to achieve full digitalization of diagnosis-design-treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0040] Figure 1 The present invention provides a flow chart of the method. DETAILED DESCRIPTION

[0041] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0042] The embodiment of the present invention discloses a method for quantitative analysis of occlusal contact for three-dimensional dentition scanning data, such as Figure 1 As shown, the following steps are included:

[0043] Use three-dimensional optical scanning to obtain triangulated mesh surface data of the upper and lower jaw dentition;

[0044] Copy the triangulated mesh surface data of the upper and lower jaw dentition and crop each tooth separately. The cropped data includes the complete occlusal surface of the tooth.

[0045] For each triangular mesh on the cut-out mesh surface of each tooth, determine whether it is an occlusal contact surface;

[0046] The bite force is calculated based on the bite contact surface and the pressure under the bite state.

[0047] First, a conventional 3D optical scan is performed to obtain triangulated surface data of the upper and lower jaw dentition (at least the complete occlusal surface), named upperjaw and lowerjaw, respectively. These data are then registered to the maximum contact position. This data can be directly acquired through intraoral scanning or by first taking a traditional impression and pouring a plaster model before scanning. This part utilizes established and mature technology.

[0048] Next, the obtained upper and lower dentition data is copied, and then each tooth is individually cropped out. The cropped data must at least contain the complete occlusal surface of the tooth, and the position of each tooth in the dentition is kept unchanged during the cropping process.

[0049] Afterwards, for each triangular mesh m on the cut-out mesh surface M of each tooth, determine whether it is an occlusal contact surface. The judgment method is to set a distance threshold th (usually 0.02-0.1mm). If the distance between the triangular mesh m and the opposing dentition surface is less than the threshold, it is determined to belong to the occlusal contact surface S (S is a collection of triangular meshes m that are very close to the opposing jaw). There are many ways to calculate the distance from the triangular mesh to the opposing dentition surface. One of the recommended methods is: first calculate the geometric center point C of the three vertices of the triangular mesh m (i.e. the average value of the three vertex coordinates), project this point onto the opposing dentition surface (projection uses the existing mature algorithm), and after obtaining the projection point, calculate the center point Cm Euclidean distance D from the projection point m , if point C m Above the curved surface of the opposing dentition, D m Take a positive value. If it is below the curved surface of the opposing dentition, D m Taking a negative value, the calculation formula to determine whether a certain triangle mesh m belongs to the occlusal contact surface S is as follows:

[0050] S={m|D m <th,m∈M}。

[0051] To simplify the model, we assume that the mechanical properties of the surfaces of all teeth in the same patient are similar. We assume that all occlusal contact surfaces are subjected to the same pressure in the occlusal state, which is set as P (this can be measured or not. If not measured, the relative bite force and direction can be calculated). From this, we can calculate the force on each triangular mesh belonging to the occlusal contact surface in the centric occlusion state. The formula is:

[0052]

[0053] (where is the bite force on the triangular mesh m, s m is the area of ​​the triangle mesh m). It should be noted that the above formula only calculates the magnitude of the force. The actual force on the triangle mesh m is a vector, and its direction is the unit normal vector of the triangle mesh (denoted as Obtained through a mature algorithm, the calculation method is the opposite of the innovation of this patent), that is:

[0054]

[0055] Based on this, the resultant occlusal force on all occlusal contact surfaces of tooth M can be calculated by the following formula:

[0056]

[0057] By performing the above operations on all teeth, the distribution of the bite force (magnitude and direction) of each tooth can be obtained.

[0058] Subsequently, the obtained occlusal force distribution is analyzed: the occlusal force of each tooth is decomposed along the occlusal plane / tooth long axis, mesiodistal direction, and buccal and lingual direction to analyze possible abnormal lateral forces; the occlusal force ratio of the left and right teeth with the same name (such as the left first molar and the right first molar) is calculated to perform a symmetry analysis; the anterior-posterior distribution balance of the occlusal force of the entire dentition is analyzed. If the occlusal force of a tooth is significantly higher than that of the adjacent tooth (such as >2 times the standard deviation), or there is an isolated high-stress contact point, it is judged as occlusal interference, and interference point identification is achieved.

[0059] When designing the occlusal form of the restoration, the appropriate occlusal force size and direction of the tooth to be restored can be determined based on the symmetry of the occlusal force, the balance of the anterior-posterior distribution, and the numerical proportional relationship of the occlusal force of each tooth in healthy people, thereby constraining the three-dimensional design form of the occlusal contact surface.

[0060] This embodiment also discloses a quantitative analysis system for occlusal contact of three-dimensional dentition scanning data, comprising:

[0061] Triangular mesh surface data acquisition module: used to acquire triangular mesh surface data of upper and lower jaw dentition using three-dimensional optical scanning;

[0062] Complete occlusal surface cropping module: used to copy the triangular mesh surface data of the upper and lower jaw teeth and crop each tooth separately. The cropped data includes the complete occlusal surface of the tooth;

[0063] Occlusal contact surface determination module: used to determine whether each triangular mesh on each cut-out tooth mesh surface is an occlusal contact surface;

[0064] Bite force calculation module: used to calculate the bite force based on the bite contact surface and the pressure under the bite state.

[0065] Finally, this embodiment discloses a computer storage medium having a computer program stored thereon. When the computer program is executed by a processor, the computer program implements any one of the steps of the method for quantitative analysis of occlusal contact for three-dimensional dentition scanning data.

[0066] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Reference can be made to the common and similar parts between the various embodiments. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the method description.

[0067] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for quantitative analysis of occlusal contact for three-dimensional dentition scanning data, characterized in that: The following steps are involved: Use three-dimensional optical scanning to obtain triangulated mesh surface data of the upper and lower jaw dentition; Copy the triangulated mesh surface data of the upper and lower jaw dentition and crop each tooth separately. The cropped data includes the complete occlusal surface of the tooth. For each triangular mesh on the cut-out mesh surface of each tooth, determine whether it is an occlusal contact surface; The bite force is calculated based on the bite contact surface and the pressure under the bite state.

2. The method for quantitative analysis of occlusal contact for three-dimensional dentition scanning data according to claim 1, characterized in that: To determine whether it is an occlusal contact surface, the judgment method is to set a distance threshold. If the distance from the triangular mesh to the opposing dentition surface is less than the threshold, it is determined to be an occlusal contact surface.

3. The method for quantitative analysis of occlusal contact for three-dimensional dentition scanning data according to claim 2, characterized in that: The distance from the triangular mesh to the opposing dentition surface is calculated as follows: calculate the geometric center point C of the three vertices of the triangular mesh m , from the geometric center point C m Project onto the opposing dentition surface to obtain the projection point and calculate the Euclidean distance D between the center point and the projection point. m If point C m Above the curved surface of the opposing dentition, D m Take a positive value. If it is below the opposing dentition surface, D m Taking a negative value, the calculation formula to determine whether a certain triangle mesh m belongs to the occlusal contact surface S is as follows: S={m|D m <th,m∈M}。 4. The method for quantitative analysis of occlusal contact for three-dimensional dentition scanning data according to claim 1, characterized in that: The specific formula for calculating the bite force is as follows: in is the bite force on the triangular mesh m, s m is the area of ​​the triangle mesh m, Is a vector whose direction is the triangle mesh unit normal vector in the opposite direction.

5. A quantitative analysis system for occlusal contact of three-dimensional dentition scanning data, characterized in that: include: Triangular mesh surface data acquisition module: used to acquire triangular mesh surface data of upper and lower jaw dentition using three-dimensional optical scanning; Complete occlusal surface cropping module: used to copy the triangular mesh surface data of the upper and lower jaw teeth and crop each tooth separately. The cropped data includes the complete occlusal surface of the tooth; Occlusal contact surface determination module: used to determine whether each triangular mesh on each cut-out tooth mesh surface is an occlusal contact surface; Bite force calculation module: used to calculate the bite force based on the bite contact surface and the pressure under the bite state.

6. A computer storage medium, characterized in that The computer storage medium stores a computer program, which, when executed by a processor, implements the steps of a method for quantitative analysis of occlusal contact of three-dimensional dentition scanning data according to any one of claims 1 to 4.

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