Method and apparatus for obtaining dental models, equipment, and medium

Abstract

The method for obtaining a dental model includes the steps of generating and displaying a current dental model according to a preset tracking and combining algorithm and the current point cloud data frame in response to the currently collected point cloud data frame of the teeth, storing the current point cloud data frame in a preset database, and determining whether a preset model update condition is satisfied based on all the point cloud data frames included in the preset database; and when the preset model update condition is satisfied, determining a reference dental model from all the point cloud data frames and updating the current dental model according to the reference dental model.

Description

Technical Field

[0001] <Cross - reference to Related Applications> This disclosure claims the priority of a Chinese patent application filed with the China National Intellectual Property Administration on June 17, 2022, with the application number 202210722394.6 and the title of the invention "Method and Apparatus, Equipment, and Medium for Obtaining Dental Models", and all of its content is incorporated herein by reference.

[0002] This disclosure relates to the technical field of 3D modeling, and particularly to a method and apparatus, equipment, and medium for obtaining dental models.

Background Art

[0003] With the continuous maturity and practical application of oral digitalization and chair - side restoration technologies, the use of intra - oral scanners has been increasing continuously. More clinics are using intra - oral scanners to scan and obtain 3D data models of teeth in patients' oral cavities. In intra - oral scanning, since it is necessary to put the intra - oral scanner into the patient's mouth for scanning and collection, its scan head is generally relatively small, and its imaging window is generally about 15 mm. Therefore, it is impossible to directly obtain 3D data of teeth across the entire oral cavity. It is necessary to move and change the position and orientation of the intra - oral scanner to obtain 3D data of teeth in different regions of the oral cavity. Furthermore, through the tracking and combination during scanning and the subsequent optimization process, a consistent and complete 3D data model of teeth is finally obtained.

[0004] In the prior art, in order to ensure that during the scanning movement of an intraoral scanner, the point cloud data frame of the teeth in the newly scanned local area can be effectively combined with the point cloud data frame of the teeth in the scanned area, the point cloud data frame of the teeth in the oral cavity is scanned while moving the intraoral scanner, and a tracking and combining technique is adopted to determine the combining position of the point cloud data frame of the newly scanned teeth. According to this combining position, the combining process of the point cloud data frame of the teeth currently being scanned is performed to obtain a dental model. In such a continuous combining method, as the moving distance of the intraoral scanner (or the range of the scanned area) increases, the error of tracking and combining accumulates. The intraoral scanner starts scanning from a certain position, continuously moves the intraoral scanner while acquiring three-dimensional data of a new area, and finally moves back to the starting position to scan, forming a moving trajectory path that connects from end to end. The obtained point cloud data frames are continuously combined to obtain a complete model of the teeth.

[0005] However, due to the existence of the combining error, in the above-mentioned tracking and combining method based on the local area, as the moving distance of the intraoral scanner (or the range of the scanned area) increases, the error of tracking and combining accumulates. When the scan loop is closed, the three-dimensional data is shifted and cannot be closed, that is, a loop-back error occurs. After the loop-back error occurs, the data inconsistency leads to a combining error or failure of subsequent scans near the loop-back closure, and the scanning cannot be effectively continued, and a complete model of the teeth in the oral cavity cannot be obtained.

Summary of the Invention

Problems to be Solved by the Invention

[0006] To solve or at least partially solve the above problems, the present disclosure provides a method and apparatus for acquiring a dental model, a device, and a medium, whereby the generation and display of the dental model and the global optimization of the dental model are performed in parallel, and the dental model is updated at an appropriate timing according to the result after global optimization, so as to avoid the problem that the error of the dental model becomes large and the point cloud data frame of the teeth cannot be continuously collected, which affects the completeness of the acquisition of the dental model, and to ensure that the dental model can be displayed in real time based on the point cloud data frame, and to realize the completeness and accuracy of the acquired dental model.

Means for Solving the Problems

[0007] An embodiment of the present disclosure includes steps of generating and displaying a current dental model according to a preset tracking and combining algorithm and the current point cloud data frame in response to the currently collected point cloud data frame of the teeth; storing the current point cloud data frame in a preset database, and determining whether a preset model update condition is satisfied based on all the point cloud data frames included in the preset database; and when the preset model update condition is satisfied, determining a reference dental model from all the point cloud data frames, and updating the current dental model according to the reference dental model. A method for acquiring a dental model is provided.

[0008] Embodiments of the present disclosure provide an apparatus for obtaining a dental model, including a display module that generates and displays a current dental model according to a preset tracking and combining algorithm and the current point cloud data frame in response to the currently collected point cloud data frame of teeth; an optimization module that stores the current point cloud data frame in a preset database and determines whether a preset model update condition is satisfied based on all the point cloud data frames included in the preset database; and an update module that determines a reference dental model from all the point cloud data frames and updates the current dental model according to the reference dental model when the preset model update condition is satisfied.

[0009] Embodiments of the present disclosure further provide an electronic device including a processor and a memory storing instructions executable by the processor. The processor reads the executable instructions from the memory and executes the instructions to implement the method for obtaining a dental model according to the embodiments of the present disclosure.

[0010] Embodiments of the present disclosure further provide a computer-readable storage medium storing a computer program for executing the method for obtaining a dental model according to the embodiments of the present disclosure. In a fourth aspect, a computer storage medium capable of storing a program that, when executed, can implement some or all of the steps in each implementation form of the communication method according to the first aspect of the present disclosure is further provided.

Advantages of the Invention

[0011] The above-described technical solutions provided by the embodiments of the present disclosure have the following advantages compared with the prior art.

[0012] In the solution for obtaining a dental model according to an embodiment of the present disclosure, in response to the currently collected point cloud data frame of the teeth, a current dental model is generated and displayed according to a preset tracking and combining algorithm and the current point cloud data frame. Further, the current point cloud data frame is stored in a preset database, and it is determined whether a preset model update condition is satisfied based on all the point cloud data frames included in the preset database. Thus, when the preset model update condition is satisfied, a reference dental model is determined from all the point cloud data frames, and the current dental model is updated based on the reference dental model. Thereby, the generation and display of the dental model and the global optimization of the dental model are performed in parallel, and by updating the dental model at an appropriate timing according to the result after global optimization, the problem that the error of the dental model becomes large and it is impossible to continue collecting the point cloud data frame of the teeth, which affects the completeness of obtaining the dental model, is avoided, and while ensuring that the dental model can be displayed in real time based on the point cloud data frame, the completeness and accuracy of the obtained dental model are realized.

[0013] It should be understood that the above general description and the following detailed description are merely exemplary and explanatory, and do not limit the present disclosure.

Brief Description of the Drawings

[0014] The accompanying drawings incorporated in the specification and constituting a part of this specification show embodiments consistent with the present disclosure and are for explaining the principles of the present disclosure together with the specification. Hereinafter, in order to more clearly explain the embodiments of the present disclosure or the technical aspects in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described. However, it goes without saying that for those skilled in the art, other drawings can be obtained based on these drawings without creative labor.

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Embodiments for Carrying Out the Invention

[0015] Hereinafter, in order to make the objectives, technical solutions, and advantages of the embodiments of the present disclosure clearer, the technical solutions in the embodiments of the present disclosure will be clearly and completely described. It goes without saying that the described embodiments are only a part, not all, of the embodiments of the present disclosure. All other embodiments obtained by those skilled in the art based on the embodiments of the present disclosure without creative labor are included in the protection scope of the present disclosure. In order to solve the above problems, an embodiment of the present disclosure provides a method for obtaining a dental model, which will be introduced below with reference to specific embodiments.

[0016] FIG. 1 is a schematic flowchart of a method for obtaining a dental model according to an embodiment of the present disclosure. This method may be executed by a dental model acquisition device, which can be realized using software and / or hardware and can generally be integrated into an electronic device. As shown in FIG. 1, this method includes steps 101 to 103.

[0017] In step 101, in response to the currently collected point cloud data frame of the teeth, a current dental model is generated and displayed according to a preset tracking and combining algorithm and the current point cloud data frame.

[0018] In an embodiment of the present disclosure, it will be understood that by moving a scanning device such as an intraoral scanner within the user's oral cavity, a current point cloud data frame in the current collection period of the corresponding teeth in the oral cavity can be obtained. The current point cloud data frame can be understood as a combination of three-dimensional data points including a plurality of scan points of teeth scanned simultaneously.

[0019] As shown in FIG. 2, since the scan window of the intraoral scanner is usually small, it is necessary to move the intraoral scanner to collect the point cloud data frame in a plurality of consecutive collection periods. What is collected in each collection period is a local tooth point cloud data frame of all the teeth in the oral cavity. Therefore, a complete model of the teeth can be obtained only by combining a plurality of point cloud data frames.

[0020] In this embodiment, after obtaining the current point cloud data frame of the teeth, the current tooth model in the current collection period is determined from the point cloud data frame.

[0021] In an embodiment of the present disclosure, when constructing and obtaining the current tooth model based on the point cloud data frame, processes such as preprocessing, segmentation, triangulation, and mesh rendering are performed on the point cloud data frame in the point cloud data frame to obtain the corresponding current tooth model. The process of constructing and obtaining the current tooth model based on the point cloud data frame is obtained from the prior art (for example, a fusion method based on an octree voxel field, etc.), so the description thereof is omitted here.

[0022] In an embodiment of the present disclosure, when the current point cloud data frame is not the first point cloud data frame, in order to indicate that a tooth model has been constructed from the point cloud data frames collected in the previous history collection periods, in this embodiment, the current tooth model is obtained according to the tracking and combining technology.

[0023] In this embodiment, a target tooth model in the previous collection cycle of the teeth is obtained, and the current point cloud data frame is combined onto the target tooth model to obtain an updated model as the current tooth model. In this embodiment, by collating the point cloud data frame in the current point cloud data frame with the point cloud data frame on the target tooth model in the previous collection cycle, or by collating with the point cloud data frame in the previous collection cycle, the overlapping area between the current point cloud data frame and the point cloud data frame on the target tooth model in the previous collection cycle is determined. Based on the overlapping area, the combination position of the current point cloud data frame is positioned, and based on this combination position, the current point cloud data frame is combined onto the target tooth model in the previous collection cycle to obtain the current tooth model in the current cycle. When combining the current point cloud data frame onto the target tooth model in the previous collection cycle, algorithms such as the Iterative Closest Point (ICP) algorithm can be adopted, but they will not be enumerated one by one here.

[0024] Furthermore, after obtaining the current tooth model, in order to realize the real-time display of the scanned tooth model, the current tooth model is displayed on a preset display interface. The preset display interface can be understood as an interactive interface that displays the model obtained after tooth scanning in real time.

[0025] In step 102, the current point cloud data frame is stored in a preset database, and based on all the point cloud data frames included in the preset database, it is determined whether the preset model update condition is satisfied.

[0026] Since the current dental model in the current collection period described above is obtained based on a bonding technique, there may be a bonding error. If the bonding error gradually accumulates, the error of the obtained dental model will increase, and when scanning one round and returning to the starting point position, the dental model may not be closed. Therefore, it is easily understood that in order to eliminate such cumulative errors, it is necessary to optimize the error of the related model. On the other hand, if it is based on a global optimization algorithm in real time, it will take a considerable amount of time. After the global optimization algorithm is completed, when displaying the optimized dental model, it will cause a display delay, which is obviously affecting the user's visual experience and scanning efficiency, etc.

[0027] In one embodiment of the present disclosure, the current point cloud data frame is stored in a preset database, and without affecting the real-time performance of the display of the current dental model, it is determined by background processing whether all the point cloud data frames stored in the preset database meet the preset model update conditions. For example, the current dental model in the current collection period is determined from the point cloud data frame, and a first thread for displaying the current dental model on a preset display interface and a second thread for storing the current point cloud data frame in a preset database and determining whether all the point cloud data frames of the teeth in the preset database meet the preset model update conditions can be pre-constructed.

[0028] In this embodiment, in order to reduce computing power consumption, instead of performing global error optimization every time a point cloud data frame is acquired, it is determined whether a preset model update condition is satisfied based on all the point cloud data frames of the teeth in a preset database. Only when the preset model update condition is satisfied, there may be a large error in the current tooth model displayed in the foreground. The current tooth model may deviate greatly from the actual teeth due to the error, affecting the display effect, and further possibly affecting the smoothness of the scan and the closure of the tooth model.

[0029] Note that depending on the application scenario, the method for determining whether a preset model update condition is satisfied based on all the point cloud data frames of the teeth in a preset database is different, and examples are as follows.

[0030] In one embodiment of the present disclosure, the current frame numbers of all the point cloud data frames included in a preset database are counted. That is, starting from the first collection, the collected point cloud data frames are counted. When the current frame number is greater than a preset number threshold, it is determined that the preset model update condition is satisfied. The preset number threshold may be calibrated by experimental data.

[0031] In one embodiment of the present disclosure, as shown in FIG. 3, the step of determining whether a preset model update condition is satisfied based on all the point cloud data frames included in a preset database includes steps 301 to 304.

[0032] In step 301, based on all the current point cloud data frames included in a preset database, the first model position of each point cloud data frame is determined.

[0033] In this embodiment, based on all the current point cloud data frames included in a preset database, the first model position of each point cloud data frame is determined. Since this first model position is obtained by performing global error optimization from all the current point cloud data frames, the accuracy of the combined position with respect to the point cloud data frame in the dental model obtained based on the tracking technology is higher.

[0034] Performing the above global error optimization from all the current point cloud data frames can be realized according to any one of the global optimization algorithms in the prior art. In some possible embodiments, the first model position of each point cloud data frame is determined based on the bundle method. The bundle method is an algorithm that combines the calculation of external calibration elements (outer points) and model point coordinates (inner points). Bundle adjustment is a non-linear function with the collinearity equation as the mathematical model and the combined position of each point cloud data frame in the three-dimensional space as the unknown, and it is calculated according to the principle of the least squares method after linearization. This calculation provides an approximate solution and then gradually iterates until it becomes the combined position value of each point cloud data frame approaching the optimal value, and this combined position value is also used as the first model position.

[0035] In step 302, the second model position of each point cloud data frame in the currently displayed dental model is determined.

[0036] In this embodiment, the second model position of each point cloud data frame in the currently displayed dental model is determined, and the second model position is the coordinate position of the corresponding point cloud data frame in the currently displayed dental model.

[0037] In step 303, the position error of each point cloud data frame is calculated from the first model position and the second model position.

[0038] The second reference dental model is the model after global optimization processing obtained based on all current point cloud data frames, while the current dental model is a rough model obtained based on the tracking and bonding technology. Therefore, the position error of each point cloud data frame is calculated from the first model position and the second model position, and based on the calculation of the position error, it is possible to determine whether the degree of error of the current dental model is large, and whether the cumulative error becomes large and the dental model may not be closed.

[0039] In some possible embodiments, the average value of the coordinate difference values between the key feature points at the first model position and the second model position may be used as the position error of each point cloud data frame.

[0040] In other possible embodiments, alignment processing of the first model position and the second model position may be performed according to the relevant alignment algorithm, optical flow information from the first model position to the second model position may be calculated, and the position error may be determined based on the optical flow information.

[0041] In step 304, based on the position error, it is determined whether a preset model update condition is satisfied.

[0042] In this embodiment, after obtaining the position error, based on the position error, it is determined whether a preset model update condition is satisfied. In some possible embodiments, the average error value of all position errors is calculated, and it is determined whether the error average value is greater than a preset average error threshold. If it is greater than the preset average error threshold, it is determined that the preset model update condition is satisfied.

[0043] In other possible embodiments, the maximum position error among all position errors is determined, and it is determined whether the maximum position error is greater than a preset maximum error threshold. If it is greater than the maximum error threshold, it is determined that the preset model update condition is satisfied.

[0044] In step 103, when the preset model update condition is satisfied, a reference dental model is determined from all point cloud data frames, and the current dental model is updated according to the reference dental model.

[0045] In this embodiment, when the preset model update condition is satisfied, a reference dental model is determined from all point cloud data frames, and the current dental model is updated based on the reference dental model. If it is not the first time that the reference dental model is generated in the background currently, the current reference dental model can be determined from all point cloud data frames based on the previous reference dental model.

[0046] In the embodiments of the present disclosure, when the preset model update condition is satisfied, that is, when the error of the currently displayed dental model may be large, in order to ensure the display effect and avoid the problem that the cumulative error becomes large and the dental model displayed in the foreground may not be closed, the currently displayed dental model is updated with a more accurate reference dental model obtained from all point cloud data frames in a preset database stored in the background, so as to improve the accuracy of the currently displayed dental model, enable the point cloud data frames of the teeth to continue to be scanned, and it can be understood that the accuracy of the currently visually displayed dental model is guaranteed.

[0047] As described above, since the generation of the reference dental model is parallel to the generation and display of the current dental model according to the preset tracking and combining algorithm and the current point cloud data frame, for example, the generation of the reference dental model can be executed in the background. The background integrates the previously acquired point cloud data frames into the currently acquired point cloud data frame each time to construct a fusion field in order to obtain a more accurate reference dental model. Also, the foreground quickly acquires and displays the current dental model based on the tracking and combining technology, and without visually delaying the display of the dental model, switches to display the more accurate reference dental model obtained in the background on the foreground as needed, thereby ensuring that the dental model can be displayed based on the point cloud data frame and realizing the integrity and accuracy of the acquired dental model.

[0048] When the collection of the point cloud data frame of the teeth is completed, the currently displayed current dental model is determined as the target dental model, that is, the last displayed target dental model is regarded as the complete dental model. When the collection of the point cloud data frame of the teeth has not been completed, the above steps are repeated until the complete dental model is gradually acquired. During the acquisition of the above dental model, if it is determined that all the point cloud data frames included in the preset database do not meet the preset model update conditions, the current dental model generated and displayed according to the preset tracking and combining algorithm and the current point cloud data frame is taken as the dental model obtained last in the current cycle.

[0049] Note that depending on the application scenario, the method for determining the reference dental model from all the point cloud data frames is different. In the embodiments of the present disclosure, since the method for determining the reference dental model from all the point cloud data frames and their spatial combination positions is obtained from the prior art (for example, the fusion method based on the octree voxel field, etc.), the description thereof is omitted here.

[0050] In some possible embodiments, as shown in FIG. 4, the step of determining the reference dental model from all the point cloud data frames includes the following steps 401 to 404.

[0051] In step 401, when the previous reference dental model determined by the previous optimization is obtained, an initial reference dental model is generated based on all the point cloud data frames included in a preset database and the first model positions of each point cloud data frame in the previous reference dental model.

[0052] It will be understood that currently, if it is not the first time that the reference dental model is constructed in the background, that is, when the previous reference dental model determined by the previous optimization is obtained, an initial reference dental model is generated based on all the point cloud data frames included in a preset database and the first model positions of each point cloud data frame in the previous reference dental model.

[0053] In an embodiment of the present disclosure, currently, if it is the first time that the reference dental model is constructed in the background, an initial reference dental model can be obtained by directly fusing all the point cloud data frames included in a preset database.

[0054] In step 402, it is determined whether the number of remaining point cloud data frames in the preset database is less than a preset number threshold.

[0055] The preset number threshold may be calibrated by experimental data.

[0056] In step 403, if it is greater than or equal to the preset number threshold, the initial reference dental model is updated according to the remaining point cloud data frames until the number of remaining point cloud data frames in the preset database is less than the preset number threshold.

[0057] In step 404, when the number of remaining point cloud data frames in the preset database is smaller than the preset number threshold, the collection of the point cloud data frames of the tooth is interrupted, and the initial reference tooth model is updated according to the remaining point cloud data frames to obtain a reference tooth model. When updating the initial reference tooth model according to the remaining point cloud data frames to obtain a reference tooth model, the bonding position on the initial reference tooth model can be determined based on local duplication, and bonding can be performed to quickly obtain a reference tooth model.

[0058] That is, in one embodiment of the present disclosure, since the scanning of the point cloud data frames by the front ground is continuous, in order to ensure that the generated initial reference tooth model contains as many collected point cloud data frames as possible, in the process of determining the reference tooth model from all the point cloud data frames described in the above embodiment, first, according to all the current point cloud data frames in the current database, an initial reference tooth model is generated by fusing based on a global optimization algorithm (the method for generating the initial reference tooth model can refer to the above embodiment, and the description thereof is omitted here). When obtaining the previous reference tooth model determined by the previous optimization, an initial reference tooth model is generated based on all the point cloud data frames included in the preset database and the first model positions of each point cloud data frame in the previous reference tooth model.

[0059] Since it takes time to generate the initial reference dental model, during the generation of the initial reference dental model, the point cloud data frame scanned by the foreground is added to the background database. Therefore, after generating the initial reference dental model, determine the remaining number of point cloud data frames in the current background database that have not participated in the generation of the initial reference dental model, and determine whether the remaining number is greater than a preset data threshold. If it is less than or equal to the preset data threshold, interrupt the scanning process, perform global optimization and fusion of the remaining point cloud data frames and the initial reference dental model to obtain an updated reference dental model, and then replace the current dental model in the foreground with the updated reference dental model. At this time, determine whether all teeth have been scanned. If not, proceed to the scanning and collection process of the next cycle.

[0060] Conversely, if it is greater than the preset data threshold, perform global optimization and fusion of the remaining point cloud data frames and the current initial reference dental model to obtain an updated initial reference dental model. At this time, repeat the above judgment. When the remaining point cloud data frames are less than or equal to the preset data threshold, interrupt the foreground scanning process, perform global optimization and fusion of the remaining point cloud data frames and the initial reference dental model to obtain an updated reference dental model. At the same time, if the preset model update condition is satisfied, replace the current dental model in the foreground with the finally obtained reference dental model. At this time, determine whether all teeth have been scanned. If not, proceed to the scanning and collection process of the next cycle.

[0061] As described above, in the method for obtaining a dental model according to an embodiment of the present disclosure, in response to the currently collected point cloud data frame of the teeth, a current dental model is generated and displayed according to a preset tracking and combining algorithm and the currently collected point cloud data frame. Further, the currently collected point cloud data frame is stored in a preset database, and based on all the point cloud data frames included in the preset database, it is determined whether a preset model update condition is satisfied. And when the preset model update condition is satisfied, a reference dental model is determined from all the point cloud data frames, and the current dental model is updated according to the reference dental model. Thereby, the generation and display of the dental model and the global optimization of the dental model are performed in parallel, and by updating the dental model at an appropriate timing according to the result after the global optimization, the error of the dental model becomes large, and the point cloud data frame of the teeth cannot be continuously collected, avoiding the problem of affecting the completeness of the acquisition of the dental model, ensuring that the dental model can be displayed in real time based on the point cloud data frame, and realizing the completeness and accuracy of the obtained dental model.

[0062] To implement the above-described embodiments, the present disclosure further proposes an apparatus for obtaining a dental model.

[0063] FIG. 5 is a schematic configuration diagram of an apparatus for obtaining a dental model according to an embodiment of the present disclosure. This apparatus can be implemented by software and / or hardware, and is generally integrated into an electronic device to perform the acquisition of a dental model. As shown in FIG. 5, this apparatus includes a display module 510, an optimization module 520, and an update module 530.

[0064] The display module 510 generates and displays a current dental model according to a preset tracking and combining algorithm and the currently collected point cloud data frame in response to the currently collected point cloud data frame of the teeth.

[0065] The optimization module 520 stores the current point cloud data frame in a preset database, and determines whether the preset model update conditions are met based on all the point cloud data frames included in the preset database.

[0066] When the preset model update conditions are met, the update module 530 determines a reference dental model from all the point cloud data frames and updates the current dental model according to the reference dental model.

[0067] The dental model acquisition device according to the embodiments of the present disclosure can execute the dental model acquisition method according to any embodiment of the present disclosure, and includes functional modules and beneficial effects corresponding to the execution of the method. In some possible embodiments, When the collection of the point cloud data frame of the teeth is completed, it further includes a model determination module that determines the currently displayed current dental model as the target dental model.

[0068] In some possible embodiments, the display module 510 specifically If the current point cloud data frame is the first point cloud data frame collected, a current dental model is constructed and displayed based on the current point cloud data frame, If the current point cloud data frame is not the first point cloud data frame collected, the most recently displayed historical dental model is obtained, The current point cloud data frame is combined on the historical dental model to obtain and display the current dental model.

[0069] In some possible embodiments, the optimization module 520 specifically Counts the current number of frames of all the point cloud data frames included in the preset database, and if the current number of frames is greater than a preset number threshold, determines that the preset model update conditions are met.

[0070] In some possible embodiments, the optimization module 520 specifically determines a first model position of each point cloud data frame based on all current point cloud data frames included in the preset database, determines a second model position of each point cloud data frame in the currently displayed dental model, calculates a position error of each point cloud data frame from the first model position and the second model position, judges whether preset model update conditions are satisfied based on the position error.

[0071] In some possible embodiments, the optimization module 520 specifically calculates an error average value of all the position errors, judges whether the error average value is greater than a preset average error threshold, and if it is greater than the preset average error threshold, determines that the preset model update conditions are satisfied.

[0072] In some possible embodiments, the optimization module 520 specifically determines a maximum position error among all the position errors, judges whether the maximum position error is greater than a preset maximum error threshold, and if it is greater than the preset maximum error threshold, determines that the preset model update conditions are satisfied.

[0073] In some possible embodiments, the update module 530 specifically When obtaining the previous reference dental model determined by the previous optimization, generates an initial reference dental model based on all point cloud data frames included in the preset database and a first model position of each point cloud data frame in the previous reference dental model, judges whether the number of remaining point cloud data frames in the preset database is smaller than a preset number threshold, When it is greater than or equal to the preset number threshold, update the initial reference dental model according to the remaining point cloud data frames in the preset database until the number of the remaining point cloud data frames in the preset database becomes smaller than the preset number threshold. When the number of the remaining point cloud data frames in the preset database is smaller than the preset number threshold, interrupt the collection of the point cloud data frames of the teeth, and update the initial reference dental model according to the remaining point cloud data frames to obtain the reference dental model.

[0074] In some possible embodiments, specifically, the update module 530 determines whether the collection of the point cloud data frames of the teeth is completed. If the collection is not completed, continue to collect the current point cloud data frames of the teeth.

[0075] To implement the above embodiments, the present disclosure further proposes a computer program product including a computer program / instruction that, when executed by a processor, implements the method for obtaining a dental model in the above embodiments.

[0076] The embodiments of the present disclosure further provide a computer storage medium that can store a program that, when executed, can implement some or all of the steps in each implementation form of the above-described method for obtaining a dental model.

[0077] FIG. 6 is a schematic configuration diagram of an electronic device according to an embodiment of the present disclosure.

[0078] Hereinafter, specifically referring to FIG. 6, a schematic configuration diagram of an electronic device 600 for realizing an embodiment of the present disclosure is shown. The electronic device 600 in the embodiment of the present disclosure may include, for example, mobile terminals such as mobile phones, notebook computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (tablet computers), PMPs (Portable Multimedia Players), in-vehicle terminals (for example, in-vehicle navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc., but is not limited thereto. The electronic device shown in FIG. 6 is merely an example and does not limit the functions and usage ranges of the embodiments of the present disclosure in any way.

[0079] As shown in FIG. 6, the electronic device 600 may include a processor (for example, a central processing unit, a graphics processor, etc.) 601 that can execute various appropriate operations and processes according to a program stored in a read-only memory (ROM) 602 or a program loaded from a memory 608 into a random access memory (RAM) 603. In the RAM 603, various programs and data necessary for the operation of the electronic device 600 are further stored. The processor 601, the ROM 602, and the RAM 603 are connected to each other via a bus 604. An input / output (I / O) interface 605 is also connected to the bus 604.

[0080] Normally, the I / O interface 605 may be connected to an input device 606 including, for example, a touch screen, a touch pad, a keyboard, a mouse, a camera, a microphone, an accelerometer, a gyroscope, etc., an output device 607 including, for example, a liquid crystal display (LCD), a speaker, an oscillator, etc., a memory 608 including, for example, a magnetic tape, a hard disk, etc., and a communication device 609. The communication device 609 enables the electronic device 600 to perform wireless or wired communication with other devices to exchange data. It should be understood that FIG. 6 shows the electronic device 600 equipped with various devices, but it is not necessary to implement or provide all the shown devices. Alternatively, more or fewer devices may be implemented or provided.

[0081] In particular, according to an embodiment of the present disclosure, the process described above with reference to the flowchart may be implemented as a computer software program. For example, an embodiment of the present disclosure includes a computer program product including a computer program carried on a non-transitory computer-readable medium, the computer program including program code for executing the method shown in the flowchart. In such an embodiment, the computer program may be downloaded and installed from a network via the communication device 609, or installed from the memory 608, or installed from the ROM 602. When the computer program is executed by the processor 601, it executes the above-described functions limited to the method for obtaining a dental model according to an embodiment of the present disclosure.

[0082] Note that the computer-readable medium of the present disclosure may be a computer-readable signal medium, a computer-readable storage medium, or any combination thereof. The computer-readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of the computer-readable storage medium may include, but are not limited to, an electrical connection having one or more conductors, a portable computer magnetic disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact magnetic disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In the present disclosure, the computer-readable storage medium may be any tangible medium that includes or stores a program that can be used by or in combination with an instruction execution system, apparatus, or device. On the other hand, in the present disclosure, the computer-readable signal medium may include a data signal propagated in a baseband or as part of a carrier wave carrying a computer-readable program code. Such a propagated data signal can use various forms, including, but not limited to, electromagnetic signals, optical signals, or any suitable combination thereof. The computer-readable signal medium may be any computer-readable medium other than the computer-readable storage medium, and this computer-readable signal medium can transmit, propagate, or transmit a program used by or in combination with an instruction execution system, apparatus, or device. The program code included in the computer-readable medium can be transmitted through any suitable medium, including, but not limited to, conductive wires, optical cables, RF (radio frequency), etc., or any suitable combination thereof.

[0083] In some embodiments, the client and the server can communicate using any currently known or future-developed network protocol such as HTTP (HyperText Transfer Protocol), and can communicate with digital data in any form or medium (e.g., via a communication network) and be interconnected. Examples of communication networks include local area networks ("LAN"), wide area networks ("WAN"), extranets (e.g., the Internet), end-to-end networks (e.g., ad hoc end-to-end networks), and any network currently known or future-developed.

[0084] The computer-readable medium may be included in the electronic device or may exist separately without being incorporated into the electronic device.

[0085] One or more programs are carried on the above computer-readable medium. When the above one or more programs are executed by this electronic device, the electronic device is caused to generate and display a current dental model according to a preset tracking combination algorithm and the current point cloud data frame in response to the currently collected point cloud data frame of the teeth. Further, the current point cloud data frame is stored in a preset database, and it is determined whether a preset model update condition is satisfied based on all the point cloud data frames included in the preset database. Thus, when the preset model update condition is satisfied, a reference dental model is determined from all the point cloud data frames, and the current dental model is updated according to the reference dental model. Thereby, the generation and display of the dental model and the global optimization of the dental model are performed in parallel, and the dental model is updated at an appropriate timing according to the result after the global optimization, so as to avoid the problem that the error of the dental model becomes large and the collection of the point cloud data frame of the teeth cannot be continued, which affects the completeness of the acquisition of the dental model, and to ensure that the dental model can be displayed in real time based on the point cloud data frame, while realizing the completeness and accuracy of the acquired dental model.

[0086] The electronic device may create computer program code for executing the operations of the present disclosure in one or more programming languages or combinations thereof. The programming languages include, but are not limited to, object-oriented programming languages such as Java, Smalltalk, C++, etc., and further include conventional procedural programming languages such as the "C" language or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, executed as an independent software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. When a remote computer is involved, 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., connected via the Internet using an Internet service provider).

[0087] Flowcharts and block diagrams in the drawings illustrate the architecture, functionality, and operation of systems, methods, and computer program products according to various embodiments of the present disclosure. In this regard, each block in the flowchart or block diagram can represent one module, program segment, or part of code that includes one or more executable instructions for realizing a given logical function. It should be noted that in some alternative implementations, the functions described in the blocks may occur in an order different from that described in the drawings. For example, two consecutively shown blocks may actually be executed substantially in parallel or in reverse order, which is determined according to the relevant functions. Also, it should be noted that each block in the block diagram and / or flowchart, and combinations of blocks in the block diagram and / or flowchart, may be realized by a dedicated system in hardware for performing a given function or operation, or may be realized by a combination of dedicated hardware and computer instructions.

[0088] The units described in the embodiments of the present disclosure may be realized by software or by hardware. The name of the unit may not limit the unit itself.

[0089] The functions described above in this specification may be executed, at least in part, by one or more hardware logic components. For example, without limitation, exemplary types of hardware logic components that can be used include field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), system on chips (SOCs), complex programmable logic devices (CPLDs), and the like.

[0090] In the context of the present disclosure, a machine-readable medium may be a tangible medium that can contain or store a program for use by or in combination with an instruction execution system, apparatus, or device. The machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. The machine-readable medium may include, but is not limited to, electronics, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination thereof. More specific examples of the machine-readable storage medium may include electrical connections by one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disc read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0091] Note that in this specification, related terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Also, since the terms "comprising", "having" or any variation thereof are intended to include non-exclusive things, a process, method, article or device comprising a series of elements includes not only these elements but also other elements not explicitly shown, or elements inherent to such a process, method, article or device. Unless there are further limitations, elements defined in the sentence "comprising one..." do not exclude the existence of other identical elements in the process, method, article or device comprising the above elements.

[0092] The above are merely specific examples of the present disclosure and are for those skilled in the art to understand or implement the present disclosure. Various modifications to these examples can be easily achieved by those skilled in the art, and the general principles defined in this specification can be implemented in other examples without departing from the spirit or scope of the present disclosure. Therefore, the present disclosure should not be limited to these examples shown in this specification, but should be adapted to the broadest scope consistent with the principles and novel features disclosed herein.

[0093] In the method for obtaining a dental model according to the present disclosure, the generation and display of the dental model and the global optimization of the dental model are performed in parallel, and the dental model is updated at an appropriate timing according to the result after global optimization, so as to avoid the problem that the error of the dental model becomes large and it is impossible to continuously collect the point cloud data frame of the teeth, which affects the completeness of the acquisition of the dental model, and to ensure that the dental model can be displayed in real time based on the point cloud data frame. On this basis, the completeness and accuracy of the obtained dental model are realized, and it has high industrial applicability.

Claims

1. responding to the currently collected point cloud data frame of the teeth, generating and displaying a current dental model according to a preset tracking and combining algorithm and the current point cloud data frame; storing the current point cloud data frame in a preset database, and determining whether a preset model update condition is satisfied based on all the point cloud data frames included in the preset database; when the preset model update condition is satisfied, determining a reference dental model from all the point cloud data frames, and updating the current dental model according to the reference dental model; A method for obtaining a dental model, characterized by comprising the above steps.

2. When the collection of the point cloud data frame of the teeth is completed, further comprising the step of determining the currently displayed current dental model as the target dental model. The method according to claim 1, characterized by the above.

3. The step of generating and displaying a current dental model according to a preset tracking and combining algorithm and the current point cloud data frame includes: when the current point cloud data frame is the first point cloud data frame collected, constructing and displaying a current dental model based on the current point cloud data frame; when the current point cloud data frame is not the first point cloud data frame collected, obtaining the most recently displayed historical dental model; combining the current point cloud data frame on the historical dental model to obtain and display a current dental model. The method according to claim 1 or 2, characterized by the above.

4. The step of determining whether a preset model update condition is satisfied based on all the point cloud data frames included in the preset database includes: counting the current number of frames of all the point cloud data frames included in the preset database, and when the current number of frames is greater than a preset number threshold, determining that the preset model update condition is satisfied. The method according to any one of claims 1 to 3, characterized by the above.

5. The step of determining whether a preset model update condition is satisfied based on all the point cloud data frames included in the preset database includes: Determining a first model position of each point cloud data frame based on all current point cloud data frames included in the preset database; Determining a second model position of each point cloud data frame in the currently displayed dental model; Calculating a position error of each point cloud data frame from the first model position and the second model position; Determining whether a preset model update condition is satisfied based on the position error, including: The method according to any one of claims 1 to 4, characterized in that.

6. The step of determining whether a preset model update condition is satisfied based on the position error is: Calculating an error average value of all the position errors; Determining whether the error average value is greater than a preset average error threshold, and if it is greater than the preset average error threshold, determining that the preset model update condition is satisfied; The method according to any one of claims 1 to 5, characterized in that.

7. The step of determining whether a preset model update condition is satisfied based on the position error is: Determining a maximum position error among all the position errors; Determining whether the maximum position error is greater than a preset maximum error threshold, and if it is greater than the preset maximum error threshold, determining that the preset model update condition is satisfied; The method according to any one of claims 1 to 6, characterized in that.

8. The step of determining a reference dental model from all the point cloud data frames is: When obtaining the previous reference dental model determined by the previous optimization, generating an initial reference dental model based on all the point cloud data frames included in the preset database and the first model position of each point cloud data frame in the previous reference dental model; Determining whether the number of remaining point cloud data frames in the preset database is less than a preset number threshold; If it is greater than or equal to the preset number threshold, updating the initial reference dental model according to the remaining point cloud data frames until the number of remaining point cloud data frames in the preset database is less than the preset number threshold; When the number of remaining point cloud data frames in the preset database is smaller than the preset number threshold, interrupt the collection of the point cloud data frame of the tooth, and update the initial reference tooth model according to the remaining point cloud data frames to obtain the reference tooth model. The method according to any one of claims 1 to 7, characterized in that.

9. Determine whether the collection of the point cloud data frame of the tooth is completed. If the collection is not completed, further include the step of continuing to collect the current point cloud data frame of the tooth. The method according to any one of claims 1 to 8, characterized in that.

10. A display module that generates and displays a current tooth model according to a preset tracking combination algorithm and the current point cloud data frame in response to the currently collected point cloud data frame of the tooth. A storage module that stores the current point cloud data frame in a preset database, and determines whether a preset model update condition is satisfied based on all the point cloud data frames included in the preset database. When the preset model update condition is satisfied, a reference tooth model is determined from all the point cloud data frames, and an update module that updates the current tooth model according to the reference tooth model. A tooth model acquisition device, characterized by comprising.

11. A processor. A memory that stores instructions executable by the processor, and the processor reads the executable instructions from the memory and executes the executable instructions to implement the method for acquiring a tooth model according to any one of claims 1 to 9. An electronic device, characterized in that.

12. A computer-readable storage medium, characterized in that a computer program for executing the method for acquiring a tooth model according to any one of claims 1 to 9 is stored. ​

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