Oral scanning method, computing device and computer program product

Abstract

The invention provides an oral cavity scanning method, computing equipment and a computer program product. The method comprises the following steps: acquiring first scanning data including three-dimensional data of a scanning rod, an auxiliary feature body and a part of dental arch through an intraoral scanner, and determining a relative position relationship of the scanning rod based on the first scanning data; the method further includes removing three-dimensional data of the scan bar and the auxiliary feature from the first scan data by automated identification, retaining three-dimensional data of a portion of the dental arch, and then acquiring second scan data including the complete dental arch. And synthesizing a three-dimensional image of the oral cavity based on the three-dimensional data of the complete dental arch, the three-dimensional data of the reserved partial dental arch and the relative position relationship of the scanning rods. According to the embodiment of the invention, on the basis of the intraoral scanning technology, the accurate relative position relation between the scanning rods is obtained by using the auxiliary feature bodies, so that the positioning accuracy of the scanning rods is ensured while the scanning process is simplified.

Description

Background Art

[0001] Intraoral scanning is the process of using specialized optical technology to digitally obtain detailed three-dimensional (3D) images of the internal structures of the oral cavity (including teeth, gums and surrounding tissues). During intraoral scanning, dental professionals use a handheld device equipped with a camera and sensors (i.e., an intraoral scanner) to take multiple images of the oral cavity from different angles. These images are transmitted to a computer workstation and then quickly stitched together using complex algorithms to generate a 3D image of the patient's teeth and soft tissues.

[0002] In dental implant technology, the scanning body is a key auxiliary tool. It is a small component that usually has a specific shape and structure and is generally installed on the implant or implant abutment. Its main function is to help the intraoral scanner accurately obtain the three-dimensional position information of the implant and its surrounding tissues. The surface of the scanning body may have special markings or geometric shapes, which make it easier for the scanner to identify and accurately record its position and angle. How to accurately position the scanning body in the mouth poses a challenge to technicians. Summary of the invention

[0003] The embodiments of the present disclosure provide an oral scanning method, a computing device and a computer program product for implementing the method. The embodiments of the present disclosure are based on intraoral scanning technology and use auxiliary feature bodies to obtain the precise relative position relationship between scanning rods, thereby simplifying the scanning process and ensuring the positioning accuracy of the scanning rods.

[0004] According to the implementation of the present disclosure, an oral scanning method is proposed. The method includes: obtaining first scanning data of the oral cavity through an intraoral scanner, wherein a plurality of scanning rods are installed in the oral cavity, and the plurality of scanning rods are respectively connected to auxiliary feature bodies, and the first scanning data includes three-dimensional data of the plurality of scanning rods, three-dimensional data of the auxiliary feature bodies, and three-dimensional data of a portion of the dental arch; based on the first scanning data, determining the relative position relationship of the plurality of scanning rods; through automatic recognition, removing the three-dimensional data of the plurality of scanning rods and the three-dimensional data of the auxiliary feature bodies from the first scanning data to retain the three-dimensional data of the portion of the dental arch; in the absence of a scanning rod in the oral cavity, obtaining second scanning data of the oral cavity through the intraoral scanner, and the second scanning data includes three-dimensional data of the complete dental arch; and synthesizing a three-dimensional image of the oral cavity based on the three-dimensional data of the complete dental arch, the retained three-dimensional data of the portion of the dental arch, and the determined relative position relationship of the plurality of scanning rods.

[0005] According to a second aspect of the present disclosure, there is provided a computing device, comprising: a processing unit; and a memory, coupled to the processing unit and containing instructions stored thereon, which, when executed by the processing unit, causes the device to perform the following actions: acquiring first scanning data of an oral cavity through an intraoral scanner, wherein a plurality of scanning rods are installed in the oral cavity, and the plurality of scanning rods are respectively connected to auxiliary feature bodies, the first scanning data comprising three-dimensional data of the plurality of scanning rods, three-dimensional data of the auxiliary feature bodies, and three-dimensional data of a portion of a dental arch; determining a relative positional relationship among the plurality of scanning rods based on the first scanning data; removing the three-dimensional data of the plurality of scanning rods and the three-dimensional data of the auxiliary feature bodies from the first scanning data through automatic recognition to retain the three-dimensional data of the portion of the dental arch; acquiring second scanning data of the oral cavity through the intraoral scanner in the absence of a scanning rod in the oral cavity, the second scanning data comprising three-dimensional data of a complete dental arch; and synthesizing a three-dimensional image of the oral cavity based on the three-dimensional data of the complete dental arch, the retained three-dimensional data of the portion of the dental arch, and the determined relative positional relationship among the plurality of scanning rods.

[0006] According to a third aspect of the present disclosure, there is provided a computer program product, which is tangibly stored in a computer storage medium and includes computer executable instructions, which, when executed by a device, cause the device to perform the following actions, the actions including: acquiring first scanning data of the oral cavity through an intraoral scanner, wherein a plurality of scanning rods are installed in the oral cavity, the plurality of scanning rods are respectively connected to auxiliary feature bodies, the first scanning data including three-dimensional data of the plurality of scanning rods, three-dimensional data of the auxiliary feature bodies, and three-dimensional data of a portion of a dental arch; determining a relative positional relationship among the plurality of scanning rods based on the first scanning data; removing the three-dimensional data of the plurality of scanning rods and the three-dimensional data of the auxiliary feature bodies from the first scanning data through automatic recognition to retain the three-dimensional data of the portion of the dental arch; acquiring second scanning data of the oral cavity through the intraoral scanner in the absence of a scanning rod in the oral cavity, the second scanning data including three-dimensional data of a complete dental arch; and synthesizing a three-dimensional image of the oral cavity based on the three-dimensional data of the complete dental arch, the retained three-dimensional data of the portion of the dental arch, and the determined relative positional relationship among the plurality of scanning rods.

[0007] According to a fifth aspect of the present disclosure, an oral scanning device is provided. The device includes: a first scanning unit, configured to acquire first scanning data of the oral cavity through an intraoral scanner, wherein a plurality of scanning rods are installed in the oral cavity, and the plurality of scanning rods are respectively connected to auxiliary feature bodies, and the first scanning data includes three-dimensional data of the plurality of scanning rods, three-dimensional data of the auxiliary feature bodies, and three-dimensional data of a portion of the dental arch; a position relationship determination unit, configured to determine the relative position relationship of the plurality of scanning rods based on the first scanning data; a data removal unit, configured to remove the three-dimensional data of the plurality of scanning rods and the three-dimensional data of the auxiliary feature bodies from the first scanning data through automatic recognition, so as to retain the three-dimensional data of the portion of the dental arch; a second scanning unit, configured to acquire second scanning data of the oral cavity through an intraoral scanner when there is no scanning rod in the oral cavity, and the second scanning data includes three-dimensional data of the complete dental arch; and an image synthesis unit, configured to synthesize a three-dimensional image of the oral cavity based on the three-dimensional data of the complete dental arch, the retained three-dimensional data of the portion of the dental arch, and the determined relative position relationship of the plurality of scanning rods.

[0008] This Summary is provided to introduce a selection of concepts in a simplified form that are further described in the Detailed Description below. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to limit the scope of the claimed subject matter. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 An exemplary environment in which various embodiments of the present disclosure can be implemented is shown;

[0010] Figure 2 A schematic diagram showing an exemplary dental arch with a scanbar installed;

[0011] Figure 3 shows an exemplary implementation of mounting a scan bar and an auxiliary feature according to some embodiments of the present disclosure;

[0012] Figure 4 Another exemplary implementation of mounting a scan bar and an auxiliary feature according to some embodiments of the present disclosure is shown;

[0013] Figure 5 A schematic flow chart of an oral scanning method according to some embodiments of the present disclosure is shown;

[0014] Figure 6 A schematic block diagram of an oral scanning device according to some embodiments of the present disclosure is shown;

[0015] Figure 7 A block diagram of a computing device capable of implementing some embodiments of the present disclosure is shown.

[0016] In these drawings, the same or similar reference symbols are used to represent the same or similar elements. The drawings are for illustrative purposes, and the sizes of the elements therein are not necessarily drawn to scale. DETAILED DESCRIPTION

[0017] The present disclosure will now be discussed with reference to several example implementations. It should be understood that these implementations are discussed only to enable those skilled in the art to better understand and thus implement the present disclosure, rather than implying any limitation on the scope of the present disclosure.

[0018] As used herein, the term "including" and variations thereof are to be interpreted as open-ended terms meaning "including but not limited to". The term "based on" is to be interpreted as "based at least in part on". The terms "an implementation" and "an implementation" are to be interpreted as "at least one implementation". The term "another implementation" is to be interpreted as "at least one other implementation". The terms "first", "second", etc. may refer to different or the same objects. Other explicit and implicit definitions may also be included below.

[0019] Implant scanning usually requires the use of some scanning rods, and the relative positions of multiple scanning rods and the position of the scanning rods relative to the dental arch in the mouth are accurately located through an intraoral scanner or an extraoral scanner. The current mainstream intraoral scanning rod is cylindrical. When using an intraoral scanner, the three-dimensional data of the patient's dental arch exposed through the cuff is usually collected first, a copy of the scanned three-dimensional data is copied, and the cuff data is removed to retain the dental arch data. Then, the scanning rod is installed on the cuff, and the three-dimensional data of the patient's dental arch with the scanning rod installed is continued to be collected on the three-dimensional data with the cuff copied and removed. Since the dental arch of the edentulous jaw is a non-rigid body, it is soft and easy to deform, and it is relatively flat, with unclear features and poor reflective properties. Therefore, the quality of the three-dimensional data collected from it is poor. Moreover, the scanning rod positioning of the traditional process is also based on the mutual registration of the three-dimensional data of the dental arch, so its accuracy is often not guaranteed.

[0020] Some existing solutions have introduced extraoral scanner technology based on intraoral scanners to solve the above-mentioned accuracy problems. The extraoral scanner uses photogrammetry technology to obtain the relative position relationship of the scanning rod, and then fuses it with the three-dimensional data of the dental arch obtained by the intraoral scanner. Although this solution improves the positioning accuracy of the scanning rod, the extraoral scanner equipment is expensive, and the process of extraoral and intraoral scanning is cumbersome, which limits its popularization.

[0021] In view of this, a solution for improving the scanning process based on intraoral scanner technology is proposed. According to the embodiment of the present disclosure, the scanning rod is rigidly connected using auxiliary feature bodies, and the auxiliary feature bodies can have rich three-dimensional features, which are helpful to accurately locate the relative position relationship between the scanning rods. In the scanning process of obtaining the scanning rod positioning information, the data of a part of the dental arch is also obtained to assist in obtaining the position relationship of the scanning rod relative to the complete dental arch. Compared with the existing solutions, the embodiments of the present disclosure improve the positioning accuracy of the scanning rod while simplifying the scanning process. The following reference Figures 1 to 7 Exemplary embodiments of the present disclosure are described in detail.

[0022] Figure 1 An exemplary environment in which multiple embodiments of the present disclosure can be implemented is shown. The exemplary environment shows an intraoral scanning system 100, which includes an intraoral scanner 110 and a computing device 120 (e.g., a laptop computer, a desktop computer, etc.) coupled together. The communication link between the intraoral scanner 110 and the computing device 120 allows the captured images to be transferred from the intraoral scanner 110 to the computing device 120 for further processing. The communication link between the intraoral scanner 110 and the computing device 120 can be a wired connection (e.g., a Universal Serial Bus USB) or a wireless connection (e.g., Wireless Fidelity Wi-Fi). It should be understood that other communication implementations are also possible.

[0023] The intraoral scanner 110 can be a handheld device that a user (dentist or related professional) can insert into the patient's mouth to capture images. As shown, the intraoral scanner 110 includes a tip 101 and a body 102. The tip 101 can be a pluggable component or can be integrated with the intraoral scanner 100. There is a camera or optical system on the top of the tip 101 for capturing images of teeth and surrounding tissues (such as gums). During the scanning process, the intraoral scanner 110 can obtain detailed information about intraoral entities, such as scanning rods, teeth, gums, and surrounding soft tissues and other oral structures, and convert the physical morphology of the oral cavity into digital image data.

[0024] The computing device 120 is the data processing and computing center of the intraoral scanning system 100. It receives the image data transmitted by the intraoral scanner 110 and processes the data using computing power. The computing device 120 uses a specific algorithm to perform splicing, fitting, and other processing on numerous discrete image data points to construct three-dimensional scanning data. The three-dimensional scanning data can be presented on the display screen 115 for users to browse and operate. The computing device 120 can also have data analysis capabilities, for example, automatically identifying the classification of data in the three-dimensional scanning data, such as dental arches, teeth, scanning rods or other components), thereby achieving image segmentation.

[0025] In some embodiments, the computing device 120 may use a deep neural network based on machine learning to implement image segmentation. Generally, machine learning can roughly include three stages, namely a training stage, a testing stage, and a use stage (also referred to as an inference stage). In the training stage, a given model can be trained using a large amount of training data, and the parameter values ​​are continuously updated iteratively until the model can obtain consistent reasoning that meets the expected goals from the training data. Through training, the model can be considered to be able to learn the association between input and output (also referred to as input-to-output mapping) from the training data. The parameter values ​​of the trained model are determined. In the testing stage, the test input is applied to the trained model to test whether the model can provide the correct output, thereby determining the performance of the model. In the use stage, the model can be used to process the actual input based on the parameter values ​​obtained from the training to determine the corresponding output.

[0026] Figure 2 FIG. 1 is a schematic diagram of an exemplary dental arch equipped with a scanning rod. As shown in the figure, a plurality of scanning rods 20 are installed on the dental arch 10. In the field of oral implantation, the scanning rod is used as an auxiliary scanning tool and is connected to the implant or implant base ( Figure 2 In the figure, the implant or implant base is blocked by the scanning body 20, not shown). The main function of the scanning rod is to help the intraoral scanner accurately obtain the three-dimensional position information of the implant in the oral cavity during the oral scanning process. Its surface usually has special markings or geometric shapes, which are designed to help the scanner recognize and accurately record the key data such as the position and angle of the implant.

[0027] In practical applications, the positioning accuracy of the scanning rod is very high. Any slight connection error may lead to inaccurate scanning data, which in turn affects the subsequent implant restoration work. For example, when making restorations such as crowns, if the scanning data is incorrect, the restoration may not be accurately matched with the implant, resulting in poor restoration effects, such as poor occlusion and loose edges.

[0028] In order to improve the positioning accuracy of the scanning rod, an improved scanning rod is provided, one end of which is fixed on the implant of the dental arch, and the other end is rigidly connected to an auxiliary feature body with scanning and identification features. During scanning, multiple scanning rods are installed in the patient's mouth, and a rigid connection is established between the scanning rods through the auxiliary feature body. The scanning rods, the auxiliary feature body and part of the dental arch are scanned in three dimensions to obtain the relative position relationship of the scanning rod and the three-dimensional data of part of the dental arch. In this article, the rigid connection can be a rigid connection relationship with physical contact, or it can be physically non-contact but close to each other, so that the same field of view of the intraoral scanner can cover multiple scanning rods or auxiliary feature bodies.

[0029] Figure 3An exemplary implementation of installing a scanning rod and an auxiliary feature body according to some embodiments of the present disclosure is shown. As shown in the figure, a dental arch 10 is equipped with a plurality of scanning rods 20, each of which is fixed on an implant implanted in the dental arch 10. One end of the auxiliary feature body 30 is connected to the scanning rod 20, for example, it can be connected to the corresponding scanning rod 20 in a detachable manner. Alternatively, the auxiliary feature body 30 can be connected to the corresponding scanning rod 20 in an integrally formed manner. In this article, the auxiliary feature body 30 can be regarded as a part of the scanning rod, and the scanning rod can be regarded as including a component 20 connected to the implant and an additional auxiliary feature body 30. In some embodiments, in a non-fastened state, the auxiliary feature body 30 can rotate around the scanning rod 20 connected thereto. During scanning, the auxiliary feature body 30 is fastened to the scanning rod 20. The other end of the auxiliary feature body 30 can extend outside the mouth. By extending the auxiliary feature body 30 outside the mouth, the patient does not need to open his mouth for a long time, which is conducive to obtaining a stable scan image and improving the patient's experience.

[0030] Outside the oral cavity, multiple auxiliary feature bodies 30 can be close to or in contact with each other, so that a single field of view of the intraoral scanner can accommodate multiple auxiliary feature bodies 30 to determine the relative positional relationship between them. Then, the relative positional relationship between multiple scanning rods 20 can be calculated based on the corresponding relationship between the posture of the auxiliary feature body 30 and the position of the scanning body 20 to which it is connected, wherein the relative positional relationship of multiple scanning rods 20 is obtained by the scanning registration relationship of the auxiliary feature bodies 30 connected to the scanning rod 20. Since these three-dimensional auxiliary feature bodies are rigid objects, have good reflective properties, and have prominent three-dimensional features, they are easy to scan and image, and obtain high-quality images, thereby greatly improving the positioning accuracy of the scanning rod.

[0031] In some implementations, the field of view of the intraoral scanner does not necessarily need to cover all the auxiliary features 30, but only needs to cover at least two scanning rods or auxiliary features, so that the relative positions of at least two scanning rods can be determined. If there are more scanning rods, the relative position relationship between all scanning rods can be determined by deducing the spatial relationship in a two-to-two manner. This can ensure that the cumulative error during actual scanning is smaller, especially the end-to-end distance between the two farthest scanning rods is minimized as much as possible by being brought together. Therefore, there is no need to scan or reconstruct the entire scanning rod (including the auxiliary feature, which can be regarded as a part of the scanning rod), only a partial area of ​​the scanning rod or the auxiliary feature needs to be scanned or reconstructed. When the field of view of the intraoral scanner can cover a partial area of ​​at least two scanning rods, the relative position relationship between the two scanning rods can be reliably determined, and then the relative position relationship between all scanning rods can be obtained.

[0032] In some embodiments, if multiple auxiliary features 30 are far apart, the end of the auxiliary feature 30 away from the scanning rod 20 can be connected to a tray 40 in an immovable manner, for example, the tray 40 is bonded to all the auxiliary features 30 outside the mouth. After installation, it is only necessary to perform a three-dimensional scan on the tray 40 and the multiple auxiliary features 30 on the tray, wherein the three-dimensional position of each auxiliary feature can uniquely determine the position of the intraoral scanning rod to which it is connected, thereby determining the relative position relationship of multiple scanning rods in the mouth.

[0033] Figure 4 Another exemplary implementation of mounting a scan bar and an auxiliary feature according to some embodiments of the present disclosure is shown. Figure 3 The auxiliary feature 30 is entirely located inside the oral cavity, and its ends away from the scanning rod 20 are close to (or in contact with) each other. Optionally, the auxiliary feature 30 can be connected to a tray 40. The tray 40 can be temporarily bonded to the dental arch 10 or the scanning rod 20.

[0034] The tray 40 can be a rigid object with a fixed shape and relatively rich three-dimensional features, and can be connected to the auxiliary feature body 30, the scanning rod 20 or the patient's dental arch 10 by mechanical fixing or bonding methods such as positioning screws and buckles. The tray can also be made of easy-to-solidify materials such as alginate and glue, and can be temporarily bonded to the auxiliary feature body 30, the scanning rod 20 or the patient's dental arch 10. The tray 40 can have rich three-dimensional features, such as a certain degree of ups and downs on the whole, and the details can be relatively rich and random, avoiding the appearance of large pieces of smooth flat surfaces. The role of the tray 40 is that when the mutual connection distance between the auxiliary feature bodies or the scanning rods is far, or the scannable range is relatively small relative to the field of view of the scanner, some rigid features on the tray can be used to help establish a better scanning registration relationship between the scanning rods.

[0035] The tray 40 is an optional auxiliary scanning accessory. Its main function is to help the scanning rods better establish a scanning alignment relationship with the help of some rigid features on the tray when the interconnected distances between scannable rigid objects (scanning rods 20 or auxiliary features 30) are far, or the scannable range of the scannable rigid objects is relatively small relative to the field of view of the scanner. If the scanning rods 20 have established a relatively close or contacting connection relationship with a sufficient scannable area through the auxiliary features 30, and multiple scanning rods (at least 2) are covered within the same field of view of the scanner and the covered scannable feature range is large enough, the tray may not be used. On the other hand, if the distances between multiple scanning rods 20 with auxiliary features 30 are far, and it is difficult for the scanner to simultaneously cover the relatively rich feature morphologies between multiple scanning rods 20 within the same field of view, the tray 40 may be used. Figure 3 and Figure 4shown.

[0036] Figure 5 Schematic flow chart of an oral scanning method 500 according to some embodiments of the present disclosure is shown. The method 500 may be performed by, for example Figure 1 The method 500 is implemented by the computing device 120 shown. It should be understood that the method 500 may also include additional actions not shown and / or may omit the actions shown, and the scope of the present disclosure is not limited in this respect.

[0037] In general, method 500 synthesizes a three-dimensional image of the oral cavity through two scans, wherein one scan is performed with a scanning rod installed in the oral cavity to obtain the relative position relationship of the scanning rod and partial dental arch data, and the other scan is performed without the scanning rod to obtain data of the complete dental arch. It should be noted that the order of the two scans can be changed, and the present disclosure does not limit this aspect. The following description is based on an example of performing a scan with a scanning rod in the oral cavity first.

[0038] The method 500 includes, at block 510, acquiring first scan data of an oral cavity by an intraoral scanner. Prior to scanning, a plurality of scan bars are installed in the oral cavity, each scan bar being connected to an auxiliary feature. The acquired first scan data includes three-dimensional data of the scan bar, three-dimensional data of the auxiliary feature, and three-dimensional data of a portion of a dental arch. Optionally, the auxiliary feature or the scan bar can be connected to a tray, and accordingly, the first scan data also includes three-dimensional data of the tray.

[0039] In box 520, based on the first scanning data, the relative position relationship of multiple scanning rods is determined. In some embodiments, the end of the auxiliary feature body away from the scanning rod can be set to be close to or in contact with each other. In this scan, a single field of view of the intraoral scanner accommodates at least two auxiliary feature bodies, so that the relative position relationship between the corresponding scanning rods connected to the auxiliary feature bodies can be determined. Specifically, the relative position relationship between the scanning rods is obtained by the scanning registration relationship of the auxiliary feature bodies without referring to the soft tissue (such as gums) in the oral cavity. Compared with soft tissue with fewer features, the auxiliary feature body is a rigid object with good reflective properties and prominent three-dimensional features, which can significantly improve the positioning accuracy of the scanning rod.

[0040] At block 530, the three-dimensional data of the plurality of scanbodies and the plurality of auxiliary features are removed from the first scan data by automated recognition to retain the three-dimensional data of the portion of the dental arch. The retained three-dimensional data of the portion of the dental arch may include data of the portion of the dental arch (e.g., gums connected to the scanbodies or near the bottom of the scanbodies).

[0041] Traditionally, the method of deleting part of the data needs to be implemented through human-computer interaction by manually specifying the range. In order to simplify the process and improve user efficiency, automatic recognition can be achieved through deep neural networks. The deep neural network can be trained to identify the point cloud category in the three-dimensional data and determine whether it belongs to a scanning rod, an auxiliary feature body or a dental arch. In some embodiments, the three-dimensional data can be classified into three categories, including dental arch categories, scanning rod categories, and auxiliary feature body categories. Alternatively, the scan data can be classified into two categories, including dental arch categories and categories of scanning rods and / or auxiliary feature rods. Then, based on the results of the automated recognition, the point clouds identified as scanning rods and auxiliary feature bodies are deleted, and the data of part of the dental arch is retained.

[0042] In some embodiments, a deep neural network can be trained by the following method. First, point cloud data of a dental arch including a scanning rod and an auxiliary feature body is collected, and the point cloud data has annotated category information. The point cloud data may include three-dimensional point coordinate information, normal vector information, color information, etc. The point cloud is manually labeled, and different types of point clouds are labeled with unique labels, for example, the label of the gum is 0, the scanning rod is 1, and the auxiliary feature body is 2, etc.

[0043] Then, the three-dimensional point cloud data is normalized and enhanced. Data normalization may include, but is not limited to, using methods such as maximum and minimum normalization and mean normalization to normalize information such as coordinates and normal vectors of the point cloud, in order to eliminate the impact of dimensional differences between data on the network. Data enhancement is used to enhance the collected point cloud to expand the data volume, for example, to create one or more rotation matrices so that the dental arch, scanning rod or auxiliary feature body has various orientations to enhance the robustness of the network.

[0044] Then, the normalized and enhanced three-dimensional point cloud data is used as training data to train a deep neural network to obtain a trained deep neural network. A classification-related deep neural network (including but not limited to a dynamic graph convolutional network, etc.) is used to perform classification training based on the training data, wherein the input of the deep neural network is the enhanced point cloud data, and the output label is the label of each point cloud. After the deep network model converges, the final network for the classification task is determined.

[0045] In block 540, without the scan bar in the oral cavity, the second scan data of the oral cavity is acquired by the intraoral scanner, and the second scan data includes the three-dimensional data of the complete dental arch. After the scanning in step 510 is completed, the scan bar, auxiliary features and tray (if any) in the oral cavity are removed, and the complete dental arch data is acquired by the intraoral scanner and transmitted to the computing device 120.

[0046] In block 550 , a three-dimensional image of the oral cavity is synthesized based on the three-dimensional data of the complete dental arch, the three-dimensional data of the retained partial dental arch, and the determined relative positional relationship of the plurality of scan arms.

[0047] Traditionally, the oral scanning system is responsible for locally collecting the scan data of the dental arch and the scanning rod, and sending the scan data to the laboratory, which synthesizes the oral image. The problem with this approach is that the laboratory may lack sufficient information to determine the positional relationship of the scanning rod relative to the dental arch. To address this problem, the computing device 120 can use the three-dimensional data of the retained portion of the dental arch to determine the positional information of the scanning rod relative to the complete dental arch, because this portion of the dental arch is adjacent to the scanning rod and carries the positional information of the scanning rod. Then, based on the positional relationship of the scanning rod relative to the complete dental arch and the relative positional relationship between the scanning rods, a three-dimensional image of the oral cavity is synthesized. The resulting three-dimensional image of the oral cavity has the spatial information of the dental arch and the precise positioning of the scanning rod therein.

[0048] Figure 6 FIG. 6 is a schematic block diagram of a device 600 for oral scanning according to an embodiment of the present disclosure. The device 600 may be implemented in Figure 1 At the computing device 120 shown. Figure 6 As shown, the device 600 includes: a first scanning unit 610 , a position relationship determining unit 620 , a data removing unit 630 , a second scanning unit 640 , and an image synthesizing unit 650 .

[0049] The first scanning unit 610 is configured to obtain first scanning data of the oral cavity through an intraoral scanner, wherein a plurality of scanning rods are installed in the oral cavity, and the plurality of scanning rods are respectively connected to the auxiliary feature bodies, and the first scanning data includes three-dimensional data of the plurality of scanning rods, three-dimensional data of the auxiliary feature bodies, and three-dimensional data of a portion of the dental arch. The position relationship determination unit 620 is configured to determine the relative position relationship of the plurality of scanning rods based on the first scanning data. The data removal unit 630 is configured to remove the three-dimensional data of the plurality of scanning rods and the three-dimensional data of the auxiliary feature bodies from the first scanning data through automatic recognition to retain the three-dimensional data of the portion of the dental arch. The second scanning unit 640 is configured to obtain second scanning data of the oral cavity through an intraoral scanner in the absence of a scanning rod in the oral cavity, and the second scanning data includes three-dimensional data of a complete dental arch. The image synthesis unit 650 is configured to synthesize a three-dimensional image of the oral cavity based on the three-dimensional data of the complete dental arch, the retained three-dimensional data of the portion of the dental arch, and the determined relative position relationship of the plurality of scanning rods.

[0050] In some embodiments, the assist feature may be removably connected to a corresponding scanbar.

[0051] In some embodiments, the assist feature may be integrally connected to the corresponding scan bar.

[0052] In some embodiments, in the unfastened state, the assist feature can rotate about the scanbar to which it is connected.

[0053] In some embodiments, one end of the assist feature is connected to the scanning rod and the other end is immovably connected to the tray having the three-dimensional feature.

[0054] In some embodiments, one end of the assist feature is connected to the scan bar and the other end is located outside of the oral cavity.

[0055] In some embodiments, one end of the plurality of auxiliary features is respectively connected to the corresponding scanning rod, and the other ends are close to or in contact with each other.

[0056] In some embodiments, when acquiring first scanning data through an intraoral scanner, a single field of view of the intraoral scanner can accommodate at least two auxiliary features, so that the relative position relationship between scanning rods connected to the at least two auxiliary features can be determined.

[0057] In some embodiments, the apparatus further comprises a data recognition unit configured to use a trained deep neural network to recognize data belonging to a dental arch and three-dimensional data belonging to the scan arm and / or the auxiliary feature in the first scan data.

[0058] In some embodiments, the positional relationship determining unit may be configured to determine the relative positional relationship of the plurality of scanning rods based on the identified three-dimensional data belonging to the auxiliary feature and / or the three-dimensional data of the plurality of scanning rods.

[0059] In some embodiments, a deep neural network can be obtained in the following manner: collecting three-dimensional point cloud data of a dental arch including a scanning rod and auxiliary feature bodies, the three-dimensional point cloud data having labeled category information; normalizing and enhancing the three-dimensional point cloud data; and using the normalized and enhanced three-dimensional point cloud data to train a deep neural network to obtain a trained deep neural network.

[0060] In some embodiments, the image synthesis unit can be configured to: determine the positional relationship of multiple scanning rods relative to the complete dental arch based on the three-dimensional data of the partial dental arch and the three-dimensional data of the complete dental arch; and synthesize a three-dimensional image of the oral cavity based on the positional relationship of the multiple scanning rods relative to the complete dental arch and the relative positional relationship between the multiple scanning rods.

[0061] In some embodiments, apparatus 600 may be implemented by a computing device that is locally connected to an intraoral scanner.

[0062] It should be noted that the reference Figure 5 Further actions or steps shown can be performed by Figure 6For example, the device 600 may include more modules or units to implement the actions or steps described above, or Figure 6 Some of the units or modules shown may be further configured to implement the actions or steps described above, which will not be repeated here.

[0063] Figure 7 A schematic block diagram of an example device 700 that can be used to implement an embodiment of the present disclosure is shown. As shown, the device 700 includes a computing unit 701, which can perform various appropriate actions and processes according to computer program instructions stored in a read-only memory (ROM) 702 or loaded from a storage unit 706 into a random access memory (RAM) 703. In the RAM 703, various programs and data required for the operation of the device 700 can also be stored. The computing unit 701, the ROM 702, and the RAM 703 are connected to each other via a bus 704. An input / output (I / O) interface 705 is also connected to the bus 704.

[0064] A number of components in the device 700 are connected to the I / O interface 705, including: an input unit 706, such as a keyboard, a mouse, etc.; an output unit 707, such as various types of displays, speakers, etc.; a storage unit 708, such as a disk, an optical disk, etc.; and a communication unit 709, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 709 allows the device 700 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0065] The computing unit 701 may be a variety of general and / or special processing components with processing and computing capabilities. Some examples of the computing unit 701 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, digital signal processors (DSPs), and any appropriate processors, controllers, microcontrollers, etc. The computing unit 701 performs the various methods and processes described above, such as method 500. For example, in some embodiments, the method 500 may be implemented as a computer software program, which is tangibly contained in a machine-readable medium, such as a storage unit 708. In some embodiments, part or all of the computer program may be loaded and / or installed on the device 700 via ROM 702 and / or communication unit 709. When the computer program is loaded into RAM 703 and executed by the computing unit 701, one or more steps of the method 500 described above may be performed. Alternatively, in other embodiments, the computing unit 701 may be configured to perform the method 500 in any other appropriate manner (e.g., by means of firmware).

[0066] In some embodiments, the methods and processes described above may be implemented as a computer program product. The computer program product may include a computer-readable storage medium carrying computer-readable program instructions for executing various aspects of the present disclosure.

[0067] A computer-readable storage medium may be a tangible device that can hold and store instructions used by an instruction execution device. A computer-readable storage medium may be, for example, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. More specific examples of computer-readable storage media (a non-exhaustive list) include: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disk read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanical encoding device, such as a punch card or a raised structure in a groove on which instructions are stored, and any suitable combination of the foregoing. As used herein, a computer-readable storage medium is not to be interpreted as a transient signal per se, such as a radio wave or other freely propagating electromagnetic wave, an electromagnetic wave propagating through a waveguide or other transmission medium (e.g., a light pulse through a fiber optic cable), or an electrical signal transmitted through a wire.

[0068] The computer-readable program instructions described herein can be downloaded from a computer-readable storage medium to each computing / processing device, or downloaded to an external computer or external storage device via a network, such as the Internet, a local area network, a wide area network, and / or a wireless network. The network can include copper transmission cables, optical fiber transmissions, wireless transmissions, routers, firewalls, switches, gateway computers, and / or edge servers. The network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards the computer-readable program instructions for storage in the computer-readable storage medium in each computing / processing device.

[0069] The computer program instructions for performing the disclosed operation may be assembler instructions, instruction set architecture (ISA) instructions, machine instructions, machine-related instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages, and conventional procedural programming languages. Computer-readable program instructions may be executed completely on a user's computer, partially on a user's computer, executed as an independent software package, partially on a user's computer, partially on a remote computer, or completely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., utilizing an Internet service provider to connect via the Internet). In certain embodiments, by utilizing the state information of a computer-readable program instruction to customize an electronic circuit, such as a programmable logic circuit, a field programmable gate array (FPGA), or a programmable logic array (PLA), the electronic circuit may execute a computer-readable program instruction, thereby realizing various aspects of the present disclosure.

[0070] These computer-readable program instructions can be provided to a processing unit of a general-purpose computer, a special-purpose computer, or other programmable data processing device, thereby producing a machine, so that when these instructions are executed by the processing unit of the computer or other programmable data processing device, a device that implements the functions / actions specified in one or more boxes in the flowchart and / or block diagram is generated. These computer-readable program instructions can also be stored in a computer-readable storage medium, and these instructions cause the computer, programmable data processing device, and / or other equipment to work in a specific manner, so that the computer-readable medium storing the instructions includes a manufactured product, which includes instructions for implementing various aspects of the functions / actions specified in one or more boxes in the flowchart and / or block diagram.

[0071] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device so that a series of operating steps are performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to implement the functions / actions specified in one or more boxes in the flowchart and / or block diagram.

[0072] The flow chart and block diagram in the accompanying drawings show the possible architecture, function and operation of the equipment, method and computer program product according to multiple embodiments of the present disclosure. In this regard, each square box in the flow chart or block diagram can represent a part of a module, program segment or instruction, and a part of the module, program segment or instruction includes one or more executable instructions for realizing the specified logical function. In some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two continuous square boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs the specified function or action, or can be implemented with a combination of special hardware and computer instructions.

[0073] Some example implementations of the present disclosure are listed below.

[0074] In a first aspect, the present disclosure provides an oral scanning method, comprising: acquiring first scanning data of an oral cavity through an intraoral scanner, wherein a plurality of scanning rods are installed in the oral cavity, the plurality of scanning rods are respectively connected to auxiliary feature bodies, the first scanning data comprising three-dimensional data of the plurality of scanning rods, three-dimensional data of the auxiliary feature bodies and three-dimensional data of a portion of a dental arch; determining a relative position relationship of the plurality of scanning rods based on the first scanning data; removing the three-dimensional data of the plurality of scanning rods and the three-dimensional data of the auxiliary feature bodies from the first scanning data through automatic recognition to retain the three-dimensional data of the portion of the dental arch; acquiring second scanning data of the oral cavity through the intraoral scanner in the absence of the scanning rod in the oral cavity, the second scanning data comprising three-dimensional data of a complete dental arch; and synthesizing a three-dimensional image of the oral cavity based on the three-dimensional data of the complete dental arch, the retained three-dimensional data of the partial dental arch, and the determined relative position relationship of the plurality of scanning rods.

[0075] In some implementations, the assist feature is removably connected to a corresponding scanbar.

[0076] In some implementations, the assist feature is integrally connected to the corresponding scan bar.

[0077] In some implementations, the assist feature can rotate about the scanbar to which it is connected in the unsecured state.

[0078] In some implementations, one end of the auxiliary feature is connected to the scanning rod, and the other end is non-movably connected to the tray having the three-dimensional feature.

[0079] In some implementations, one end of the assist feature is connected to the scan bar and the other end is located outside of the oral cavity.

[0080] In some implementations, one end of the plurality of auxiliary features is respectively connected to the corresponding scanning rod, and the other ends of the plurality of auxiliary features are close to or in contact with each other.

[0081] In some implementations, when the first scanning data is acquired using the intraoral scanner, a single field of view of the intraoral scanner can accommodate at least two auxiliary features, so that the relative position relationship between the scanning rods connected to the at least two auxiliary features can be determined.

[0082] In some implementations, the method further includes using a trained deep neural network to identify data belonging to a dental arch and three-dimensional data belonging to the scanbar and / or the auxiliary feature in the first scan data.

[0083] In some implementations, determining the relative positional relationship of the plurality of scan bars includes determining the relative positional relationship of the plurality of scan bars based on the identified three-dimensional data belonging to the auxiliary feature and / or the three-dimensional data of the plurality of scan bars.

[0084] In some implementations, the deep neural network is obtained in the following manner: collecting three-dimensional point cloud data of the dental arch including the scanning rod and the auxiliary feature body, the three-dimensional point cloud data having labeled category information; normalizing and enhancing the three-dimensional point cloud data; and using the normalized and enhanced three-dimensional point cloud data to train the deep neural network to obtain the trained deep neural network.

[0085] In some implementations, synthesizing the three-dimensional image of the oral cavity includes: determining the positional relationship of the multiple scanning arms relative to the complete dental arch based on the three-dimensional data of the partial dental arch and the three-dimensional data of the complete dental arch; and synthesizing the three-dimensional image of the oral cavity based on the positional relationship of the multiple scanning arms relative to the complete dental arch and the relative positional relationship between the multiple scanning arms.

[0086] In some implementations, the method is performed by a computing device locally connected to the intraoral scanner.

[0087] In a second aspect, the present disclosure provides a computing device, comprising: a processing unit; and a memory, coupled to the processing unit and containing instructions stored thereon, the instructions, when executed by the processing unit, causing the device to perform the following actions:

[0088] Acquire first scanning data of the oral cavity by an intraoral scanner, wherein a plurality of scanning rods are installed in the oral cavity, and the plurality of scanning rods respectively have or are connected to auxiliary feature bodies, and the first scanning data at least includes three-dimensional data of the plurality of scanning rods and a part of the dental arch;

[0089] Determining the relative position relationship of the plurality of scanning rods based on the first scanning data;

[0090] Removing the three-dimensional data of the plurality of scan bars and the plurality of auxiliary features from the first scan data by automated recognition to retain the three-dimensional data of the portion of the dental arch;

[0091] In the absence of the scanning rod in the oral cavity, acquiring second scanning data of the oral cavity by using the intraoral scanner, wherein the second scanning data includes three-dimensional data of a complete dental arch; and

[0092] A three-dimensional image of the oral cavity is synthesized based on the three-dimensional data of the complete dental arch, the retained three-dimensional data of the partial dental arch, and the determined relative positional relationship of the plurality of scanning rods.

[0093] In some implementations, when the first scan data is acquired using the intraoral scanner, a single field of view of the intraoral scanner includes the auxiliary feature connected to at least two scanning rods, so that a relative positional relationship between the at least two scanning rods can be determined.

[0094] In some implementations, the actions further include: using a trained deep neural network to identify data belonging to a dental arch and three-dimensional data belonging to the scanbar and / or the auxiliary feature in the first scan data.

[0095] In some implementations, determining the relative positional relationship of the plurality of scan bars includes determining the relative positional relationship of the plurality of scan bars based on the identified three-dimensional data belonging to the auxiliary feature and / or the three-dimensional data of the plurality of scan bars.

[0096] In some implementations, synthesizing the three-dimensional image of the oral cavity includes: determining the positional relationship of the multiple scanning arms relative to the complete dental arch based on the three-dimensional data of the partial dental arch and the three-dimensional data of the complete dental arch; and synthesizing the three-dimensional image of the oral cavity based on the positional relationship of the multiple scanning arms relative to the complete dental arch and the relative positional relationship between the multiple scanning arms.

[0097] In a third aspect, a computer program product is provided, the computer program product being tangibly stored in a computer storage medium and comprising computer executable instructions, which when executed by a device cause the device to perform the following actions, the actions comprising:

[0098] Acquire first scanning data of the oral cavity by an intraoral scanner, wherein a plurality of scanning rods are installed in the oral cavity, and the plurality of scanning rods respectively have or are connected to auxiliary feature bodies, and the first scanning data at least includes three-dimensional data of the plurality of scanning rods and a part of the dental arch;

[0099] Determining the relative position relationship of the plurality of scanning rods based on the first scanning data;

[0100] Removing the three-dimensional data of the plurality of scan bars and the plurality of auxiliary features from the first scan data by automated recognition to retain the three-dimensional data of the portion of the dental arch;

[0101] In the absence of the scanning rod in the oral cavity, acquiring second scanning data of the oral cavity by using the intraoral scanner, wherein the second scanning data includes three-dimensional data of a complete dental arch; and

[0102] A three-dimensional image of the oral cavity is synthesized based on the three-dimensional data of the complete dental arch, the retained three-dimensional data of the partial dental arch, and the determined relative positional relationship of the plurality of scanning rods.

[0103] In a fourth aspect, the present disclosure provides a computer-readable medium having machine-executable instructions stored thereon, which, when executed by a device, cause the device to perform one or more implementations of the method of the first aspect described above.

[0104] The embodiments of the present disclosure have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. An oral scanning method, comprising: Acquire first scanning data of the oral cavity by an intraoral scanner, wherein a plurality of scanning rods are installed in the oral cavity, and the plurality of scanning rods are respectively connected to the auxiliary feature bodies, and the first scanning data includes three-dimensional data of the plurality of scanning rods, three-dimensional data of the auxiliary feature bodies, and three-dimensional data of a part of the dental arch; Determining the relative position relationship of the plurality of scanning rods based on the first scanning data; Removing the three-dimensional data of the plurality of scan bars and the three-dimensional data of the auxiliary feature from the first scan data through automated recognition to retain the three-dimensional data of the portion of the dental arch; In the absence of the scanning rod in the oral cavity, obtaining second scanning data of the oral cavity by using the intraoral scanner, wherein the second scanning data includes three-dimensional data of a complete dental arch; as well as A three-dimensional image of the oral cavity is synthesized based on the three-dimensional data of the complete dental arch, the retained three-dimensional data of the partial dental arch, and the determined relative positional relationship of the plurality of scanning rods.

2. The oral scanning method according to claim 1, wherein: The assist feature is removably connected to a corresponding scan bar.

3. The oral scanning method according to claim 1, wherein: The auxiliary feature is connected to the corresponding scanning rod in an integrally formed manner.

4. The oral cavity scanning method according to any one of claims 1 to 3, wherein: In the unfastened state, the auxiliary feature can rotate around the scanning rod connected thereto.

5. The method according to any one of claims 1 to 3, wherein: One end of the auxiliary feature body is connected to the scanning rod, and the other end is immovably connected to the tray with three-dimensional features.

6. The method according to claim 1, wherein: One end of the auxiliary feature is connected to the scanning rod, and the other end is located outside the oral cavity.

7. The method according to claim 1, wherein: One ends of the plurality of auxiliary feature bodies are respectively connected to corresponding scanning rods, and the other ends thereof are close to or in contact with each other.

8. The method according to claim 1, wherein: When the intraoral scanner is used to acquire the first scanning data, a single field of view of the intraoral scanner can accommodate at least two auxiliary features, so that the relative position relationship between the scanning rods connected to the at least two auxiliary features can be determined.

9. The method according to claim 1, further comprising: The trained deep neural network is used to identify data belonging to a dental arch and three-dimensional data belonging to the scanbar and / or the auxiliary feature in the first scan data.

10. The method according to claim 9, wherein: Determining the relative position relationship of the plurality of scanning rods comprises: Based on the identified three-dimensional data belonging to the auxiliary feature and / or the three-dimensional data of the plurality of scan bars, a relative positional relationship of the plurality of scan bars is determined.

11. The method according to claim 9, wherein: The deep neural network is obtained by: Collecting three-dimensional point cloud data of a dental arch including the scanning rod and the auxiliary feature body, wherein the three-dimensional point cloud data has annotated category information; Normalizing and enhancing the three-dimensional point cloud data; as well as A deep neural network is trained using the normalized and enhanced three-dimensional point cloud data to obtain the trained deep neural network.

12. The method according to claim 1, wherein: Synthesizing the three-dimensional image of the oral cavity comprises: Determining a positional relationship of the plurality of scanning rods relative to the complete dental arch based on the three-dimensional data of the partial dental arch and the three-dimensional data of the complete dental arch; and A three-dimensional image of the oral cavity is synthesized based on the positional relationship of the plurality of scanning arms relative to the complete dental arch and the relative positional relationship between the plurality of scanning arms.

13. The method of claim 1 performed by a computing device locally connected to the intraoral scanner.

14. A computing device comprising: Processing unit; as well as A memory coupled to the processing unit and containing instructions stored thereon, which, when executed by the processing unit, cause the device to perform the following actions: Acquire first scanning data of the oral cavity by an intraoral scanner, wherein a plurality of scanning rods are installed in the oral cavity, and the plurality of scanning rods are respectively connected to the auxiliary feature bodies, and the first scanning data includes three-dimensional data of the plurality of scanning rods, three-dimensional data of the auxiliary feature bodies, and three-dimensional data of a part of the dental arch; Determining the relative position relationship of the plurality of scanning rods based on the first scanning data; Removing the three-dimensional data of the plurality of scan bars and the three-dimensional data of the auxiliary feature from the first scan data through automated recognition to retain the three-dimensional data of the portion of the dental arch; In the absence of the scanning rod in the oral cavity, obtaining second scanning data of the oral cavity by using the intraoral scanner, wherein the second scanning data includes three-dimensional data of a complete dental arch; as well as A three-dimensional image of the oral cavity is synthesized based on the three-dimensional data of the complete dental arch, the retained three-dimensional data of the partial dental arch, and the determined relative positional relationship of the plurality of scanning rods.

15. The computing device of claim 14, wherein: When the intraoral scanner is used to acquire the first scanning data, a single field of view of the intraoral scanner can accommodate at least two auxiliary features, so that the relative position relationship between the scanning rods connected to the at least two auxiliary features can be determined.

16. The computing device of claim 14, the actions further comprising: The trained deep neural network is used to identify data belonging to a dental arch and three-dimensional data belonging to the scanbar and / or the auxiliary feature in the first scan data.

17. The computing device of claim 16, wherein determining the relative positional relationship of the plurality of scanning rods comprises: Based on the identified three-dimensional data belonging to the auxiliary feature and / or the three-dimensional data of the plurality of scan bars, a relative positional relationship of the plurality of scan bars is determined.

18. The computing device of claim 14, wherein: Synthesizing the three-dimensional image of the oral cavity comprises: Determining a positional relationship of the plurality of scanning rods relative to the complete dental arch based on the three-dimensional data of the partial dental arch and the three-dimensional data of the complete dental arch; and A three-dimensional image of the oral cavity is synthesized based on the positional relationship of the plurality of scanning arms relative to the complete dental arch and the relative positional relationship between the plurality of scanning arms.

19. A computer program product tangibly stored in a computer storage medium and comprising computer executable instructions which, when executed by a device, cause the device to perform the following actions, the actions comprising: Acquire first scanning data of the oral cavity by an intraoral scanner, wherein a plurality of scanning rods are installed in the oral cavity, and the plurality of scanning rods are respectively connected to the auxiliary feature bodies, and the first scanning data includes three-dimensional data of the plurality of scanning rods, three-dimensional data of the auxiliary feature bodies, and three-dimensional data of a part of the dental arch; Determining the relative position relationship of the plurality of scanning rods based on the first scanning data; Removing the three-dimensional data of the plurality of scan bars and the three-dimensional data of the auxiliary feature from the first scan data through automated recognition to retain the three-dimensional data of the portion of the dental arch; In the absence of the scanning rod in the oral cavity, obtaining second scanning data of the oral cavity by using the intraoral scanner, wherein the second scanning data includes three-dimensional data of a complete dental arch; as well as A three-dimensional image of the oral cavity is synthesized based on the three-dimensional data of the complete dental arch, the retained three-dimensional data of the partial dental arch, and the determined relative positional relationship of the plurality of scanning rods.

Images