Method and equipment for three-dimensional overlapping measurement of teeth and facial bones using the entire skull base as the reference plane

Abstract

The present invention proposes a method and apparatus for three-dimensional overlay measurement of teeth and facial bones using the entire skull base as a reference plane. This method obtains CBCT (cone-beam computed tomography) data from the preceding and following phases to be compared, converts the CBCT data format, and then constructs three-dimensional models of the teeth and jaws for comparison. The coordinate system is then determined, and the landmarks of the entire skull base plane, including the skull base point (Ba), nasion point (N), bilateral supraorbital notches (UOrN), and bilateral infraorbital margin midpoints (O), are marked to determine the standard skull base plane. Using this standard plane as the reference plane, the CBCT data to be compared are overlaid. After automatic computer recognition, the overlay is re-registered, and the three-dimensional changes in the teeth, alveolar bones, and facial bones are marked and measured. Through the present invention, CBCT data of a patient's dentition and jaw can be converted into 3D models and overlaid, enabling the evaluation and measurement of changes in the teeth and jaws in three dimensions.

Description

Technical Field

[0001] The present invention relates to the field of three-dimensional measurement technology, and in particular to a method, device, equipment and storage medium for three-dimensional overlapping measurement of teeth and facial bones using the entire skull base as a reference plane. Background Art

[0002] Cephalometric measurement is an essential method for clinical orthodontic work. It measures the patient's teeth, jaws, and soft tissues before, during, and after treatment, providing reliable information for clinical diagnosis, rational treatment planning, and postoperative efficacy analysis. However, this method is susceptible to interference from overlapping or inaccurate fixed points, resulting in the inability to accurately measure some clinical indicators of interest. In addition, cephalometric measurement only reflects the two-dimensional position changes of the jaws and teeth in the sagittal and vertical directions, and cannot simultaneously achieve measurement and analysis in three-dimensional directions such as sagittal, vertical, and horizontal directions, limiting its scope of application.

[0003] With the clinical application of cone-beam CT (CBCT), comprehensive 3D data of the skull, jaw, and teeth can be simultaneously acquired. Existing software effectively establishes methods for measuring hard tissues such as the skull, jaw, and teeth in sagittal, vertical, and horizontal directions. Therefore, we propose a new 3D comparative measurement method that, using only CBCT data, can convert and overlay 3D models of the skull, jaw, and teeth at different stages, clearly demonstrating the dynamic changes in tooth movement and jaw morphology in 3D.

[0004] The goal of orthodontics is to better coordinate the relationship between teeth, jaws, and face. Understanding the relative position of teeth and jaws is crucial before, during, and after treatment to rationally plan treatment, adjust treatment options, and explore related mechanisms. Therefore, establishing a rational and effective three-dimensional measurement method for teeth and jaws has significant clinical application value and is a technical means to achieve precise orthodontic treatment.

[0005] Traditional comparative measurement methods include: Method 1, overlapping the lateral skull films that need to be compared, and evaluating the changes in the teeth and jaws by tracing the position changes of each landmark point. The disadvantages of this method are: it is difficult to achieve accurate repetition of the head position in each shot of the lateral skull film, and the lateral skull film is a two-dimensional imaging material. The overlap of the bilateral maxillofacial tissues affects the clarity of the results and easily causes errors in the fixed points. In addition, when the projection plane rotates, the tracing points of the lateral skull film become unreliable. Therefore, this method is affected by changes in head position and inaccurate fixed points, and can only reflect the approximate two-dimensional position changes of the jaws and teeth, but cannot accurately measure the distance they move.

[0006] Method 2: Cone-beam CT (CBCT) data is converted into a model and registered with tooth data acquired by an oral scanner to measure tooth movement distance before and after treatment. The disadvantages of this method are: long intraoral scanning times, requiring repeated scans for complex structures, resulting in a large workload; reuse of the oral scanner probe can easily lead to cross-infection; the oral scanner and CBCT model use different coordinate systems when constructing the 3D model, resulting in registration errors; and the oral scanner can only obtain data on the crown portion of the tooth, meaning that only the crown portion can be compared, lacking information on root morphology and jaw bone changes. This makes it impossible to match the root and jaw bone data from the CBCT scan during comparison, resulting in data waste.

[0007] In summary, the shortcomings of traditional comparison methods are as follows: due to the limitation of two-dimensional planes, the overlapping results of lateral skull radiographs cannot reflect the three-dimensional changes of the dentition and jaw; due to the influence of the overlap of soft and hard tissues on both sides, the distance measurement results are not accurate enough; oral scans need to be performed inside the patient's mouth, which increases the difficulty of operation and is not conducive to the implementation of epidemic prevention work; oral scans can only obtain data on the crowns, while root and jaw data are missing. Therefore, we proposed a new three-dimensional comparison measurement method, which can realize the transformation and overlap of the three-dimensional models of teeth and jaws only through CBCT data, and clearly show the morphological and positional changes of the overall teeth and jaws. This method optimizes the existing three-dimensional plane overlap measurement method, can help clinical workers observe the direction and position of the three-dimensional movement of teeth and jaws, and has intuitive and visual clinical guidance significance. Summary of the Invention

[0008] The present invention provides a method, device, equipment, and storage medium for measuring the three-dimensional overlap of teeth and facial bones using the entire skull base as a reference plane. The method aims to help clinical workers observe the direction and position of the three-dimensional movement of teeth and jaws, and has intuitive and visual clinical guidance significance.

[0009] To this end, the first object of the present invention is to provide a three-dimensional overlapping measurement method of teeth and facial bones using the entire skull base as a reference plane, comprising:

[0010] Acquire the before-and-after cone beam computed tomography (CBCT) data to be compared and convert the CBCT data format;

[0011] Build and compare three-dimensional models of the front and back teeth and jaws, determine the coordinate system, mark the landmark points of the entire skull base plane to determine the standard skull base plane;

[0012] Using the standard plane as the reference plane, the CBCT data will need to be compared and overlapped, and the overlap and points will be identified and aligned to measure the changes in the teeth, alveolar bones, and facial and maxillary bones in the three-dimensional direction.

[0013] The steps of establishing and comparing three-dimensional models of the front and back teeth and jaws include:

[0014] Obtain the target dentition and jaw data of the patient to be compared through CBCT scanning, and import the CBCT data into the modeling software in DICOM format;

[0015] Generate the three-dimensional coordinates of the model, adjust the contrast of the model, separate the upper and lower jaws and upper and lower dentitions through threshold segmentation, and perform three-dimensional reconstruction;

[0016] Use modeling software to cut the model, cut the jaw and teeth into separate parts, and create them into groups.

[0017] Among them, in the step of marking the landmark point of the whole skull base plane to determine the standard skull base plane,

[0018] The skull base point (Ba), nasion point (N), bilateral supraorbital notches (UOrN), and bilateral midpoints of the infraorbital margins (O) of the whole skull base plane were marked as landmarks;

[0019] The standard plane is determined by the landmark points, and the CBCT data models to be compared are preliminarily overlapped using the standard plane as a reference plane, and then automatically aligned and overlapped by a computer.

[0020] Among them, using the standard plane as the reference plane, it is necessary to compare the CBCT data for overlap, identify and perform registration overlap and mark points, and measure the changes of teeth, alveolar bones and facial and maxillary bones in the three-dimensional direction, including:

[0021] By adjusting different colors and transparency, the two CBCT data models that need to be compared are distinguished;

[0022] Mark the measuring points on the teeth or jaws in the three-dimensional direction, and measure the three-dimensional movement position change of the same point on the overlapped model to obtain the movement distance of the teeth and jaws;

[0023] Separate the overlapping model of the target tooth or jaw part and measure the rotation and axial inclination angles based on the long axis of the tooth. Measure the rotation angle of the maxilla based on the ANS-PNS and the rotation angle of the mandible based on the mandibular plane.

[0024] The cone beam computed tomography (CBCT) data at least includes three-dimensional data of the position and morphological structure of the maxilla, mandible, alveolar bone, dentition, tooth crowns, and tooth roots.

[0025] Among them, the measurement points of the marked teeth are the root apex or tooth cusp points of the target teeth before and after treatment, and the movement distances of the root apex and tooth cusp points along the X-axis, Y-axis, and Z-axis before and after orthodontic treatment are measured respectively to quantify the three-dimensional movement of the teeth.

[0026] Among them, the marking of the mandibular landmarks includes selecting the upper alveolar seat point, anterior nasal ridge point, nasion point, infraorbital point, etc., and measuring the movement distance of the same landmark along the X-axis, Y-axis, and Z-axis before and after orthodontic treatment to quantify the three-dimensional movement coordinate system of the mandible;

[0027] The tooth rotation angle is the rotation angle of the tooth around the long axis of the tooth observed after overlapping the three-dimensional models;

[0028] The mandibular rotation angle is the rotation angle of the maxilla around the ANS-PNS or the rotation angle of the mandibular around the mandibular plane observed after overlapping the three-dimensional models.

[0029] A second object of the present invention is to provide a three-dimensional tooth and facial bone overlap measurement device using the entire skull base as a reference plane, comprising:

[0030] A data acquisition module, used to acquire cone beam computed tomography (CBCT) data before and after comparison and convert the CBCT data format;

[0031] The model building module is used to build three-dimensional models of the front and back teeth and jaws, determine the coordinate system, mark the landmark points of the entire skull base plane, and determine the standard skull base plane;

[0032] The measurement module is used to overlap the CBCT data that needs to be compared using the standard plane as the reference plane, identify and perform registration overlap and mark points, and measure the changes of teeth, alveolar bones and facial and maxillary bones in the three-dimensional direction.

[0033] The third object of the present invention is to provide an electronic device, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute each step in the method of the aforementioned technical solution.

[0034] A fourth object of the present invention is to provide a non-transitory computer-readable storage medium storing computer instructions, wherein the computer instructions are used to enable a computer to execute each step in the method according to the aforementioned technical solution.

[0035] Different from the existing technology, the present invention provides a three-dimensional overlapping measurement method for teeth and facial bones using the entire skull base as the reference plane. By obtaining the CBCT (cone-beam computed tomography) data of the front and back stages to be compared and converting the CBCT data format, a three-dimensional model of the front and back teeth and jaws is established respectively. The coordinate system is determined, and the landmark points of the entire skull base plane, the skull base point (Ba) and the nasion point (N), are marked to determine the standard skull base plane. With the standard plane as the reference plane, the CBCT data to be compared are overlapped. After automatic recognition by the computer, the overlap is re-aligned, and the changes in the teeth, alveolar bones, and facial and maxillary bones in the three-dimensional direction are marked and measured. Through the present invention, the CBCT data of the patient's dentition and jaw can be converted into a 3D model and overlapped, realizing the evaluation and measurement of changes in the teeth and jaws in the three-dimensional direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The present invention and / or additional aspects and advantages will become apparent and readily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0037] Figure 1 The present invention provides a schematic flow chart of a method for three-dimensional overlapping measurement of teeth and facial bones using the entire skull base as a reference plane.

[0038] Figure 2 This is a schematic diagram of the landmark points of the skull base point (Ba), nasion point (N), bilateral supraorbital notches (UOrN), and bilateral infraorbital margin midpoint (O) in a three-dimensional overlapping measurement method of teeth and facial bones with the entire skull base as the reference plane provided by the present invention.

[0039] Figure 3 This is a schematic diagram of the three-dimensional movement distance of the same marked point on the XYZ axis after treatment in a three-dimensional overlap measurement method of teeth and facial bones with the entire skull base as the reference plane provided by the present invention.

[0040] Figure 4 This is a schematic diagram of the changes in the opening and closing of the anterior dentition with age in a three-dimensional overlapping measurement method of teeth and facial bones with the entire skull base as the reference plane provided by the present invention.

[0041] Figure 5 This is a schematic diagram of landmark points when measuring using the upper alveolar seat point (point A) and other landmark points in a three-dimensional overlapping measurement method of teeth and facial bones with the entire skull base as the reference plane provided by the present invention.

[0042] Figure 6 This is a side schematic diagram of the backward movement of the upper alveolar seat point (point A) when measuring the three-dimensional overlapping measurement method of teeth and facial bones with the entire skull base as the reference plane provided by the present invention.

[0043] Figure 7The present invention provides a schematic structural diagram of a three-dimensional tooth and facial bone overlap measurement device using the entire skull base as a reference plane.

[0044] Figure 8 It is a structural schematic diagram of a non-transitory computer-readable storage medium storing computer instructions provided by the present invention. DETAILED DESCRIPTION

[0045] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present invention, but are not to be construed as limiting the present invention.

[0046] like Figure 1 As shown in FIG. 1 , a three-dimensional overlapping measurement method of teeth and facial bones using the entire skull base as a reference plane is provided in an embodiment of the present invention, specifically comprising:

[0047] S110: Acquire cone beam computed tomography (CBCT) data of the preceding and following stages to be compared, and convert the CBCT data format.

[0048] Obtain the target dentition and jaw data of the patient to be compared through CBCT scanning, and import the CBCT data into the modeling software in DICOM format;

[0049] Generate the three-dimensional coordinates of the model, adjust the contrast of the model, and separate the upper and lower jaws and upper and lower dentitions through threshold segmentation for three-dimensional reconstruction. The three-dimensional coordinates are automatically generated by the modeling software based on the imported CBCT three-dimensional data. Threshold segmentation is to adjust the contrast to create a sharp contrast between the bone and teeth, and separate the upper and lower jaws and upper and lower dentitions using appropriate threshold units, save them as "STL" format files, and perform three-dimensional reconstruction.

[0050] Use modeling software to cut the model, dividing the jaw and teeth into separate parts and creating groups. Model cutting involves cutting and trimming along the edges of the target dentition and jaw in the modeling software, cutting the target dentition and jaw into separate parts with clear edges. Creating groups involves fixing the pre-treatment jaw data to keep the coordinates fixed and creating a group with the treated jaw and dentition, allowing the treated dentition to move with the entire jaw.

[0051] S120: Establish and compare three-dimensional models of the front and back teeth and jaws, determine the coordinate system, mark the landmark points of the entire skull base plane, and determine the standard skull base plane.

[0052] The skull base point (Ba), nasion point (N), bilateral supraorbital notches (UOrN), and bilateral midpoints of the infraorbital margins (O) of the whole skull base plane were marked as landmarks;

[0053] The standard plane is determined by the landmark points, and the CBCT data models to be compared are preliminarily overlapped using the standard plane as a reference plane, and then automatically aligned and overlapped by a computer.

[0054] After the preliminary overlapping model is formed, the computer automatically identifies the points at the same position on the model and overlaps them again. This is repeated many times to improve the accuracy of the registration. The registration is repeated until the error value displayed by the computer no longer decreases. The overlapped data is saved in STL format.

[0055] S130: Using the standard plane as the reference plane, the CBCT data to be compared are overlapped, and registration overlap and mark points are identified and performed to measure the changes of the teeth, alveolar bones, and facial and maxillary bones in the three-dimensional direction.

[0056] The two CBCT data models that need to be compared are distinguished by adjusting different colors, transparency, etc.

[0057] Mark the measurement points on the teeth or jaws in the three-dimensional direction, and measure the three-dimensional movement position changes of the same point on the overlapped model to obtain the movement distance of the teeth and jaws.

[0058] Separate the overlapping model of the target tooth or jaw part and measure the rotation and axial inclination angles based on the long axis of the tooth. Measure the rotation angle of the maxilla based on the ANS-PNS and the rotation angle of the mandible based on the mandibular plane.

[0059] When measuring teeth, the tooth model can be separated to prevent the measurement results from being affected by the adjacent teeth and surrounding alveolar bones of the target tooth. The change in the overall position of the target tooth relative to the dentition can also be observed in the dentition.

[0060] When measuring the jaw, the jaw model can be separated to avoid the measurement results being affected by the dentition or other facial bones.

[0061] The measurement points of the marked teeth are the root apex or tooth cusp of the target tooth before and after treatment. The movement distances of the root apex and tooth cusp along the X-axis, Y-axis, and Z-axis are measured before and after orthodontic treatment to quantify the three-dimensional movement of the tooth. The physical meaning of the coordinate system is described in Table 1 below:

[0062]

[0063] Table 1 Physical meaning of coordinate system

[0064] The mandibular landmarks were marked by selecting the upper alveolar seat point, anterior nasal ridge point, nasion point, infraorbital point, etc., and measuring the movement distance of the same landmark along the X-axis, Y-axis, and Z-axis before and after orthodontic treatment to quantify the three-dimensional movement coordinate system of the mandible.

[0065] The tooth rotation angle is the rotation angle of the tooth around the long axis of the tooth observed after superimposing the three-dimensional model.

[0066] The mandibular rotation angle is the rotation angle of the maxilla around the ANS-PNS or the rotation angle of the mandible around the mandibular plane observed after superimposing the three-dimensional models; other measurement indicators can be added and applied according to the doctor's needs.

[0067] The specific implementation steps of this case are:

[0068] Example 1: In this example, the patient's right maxillary posterior teeth are impacted. After traction is applied to the impacted teeth, the curved surface tomography and lateral skull radiographs can only show the movement of the impacted teeth in the two-dimensional direction. Since the movement amplitude is very small, the specific amount of movement is unknown. The CBCT data of the patient's entire skull before and after treatment are scanned and imported into the modeling software in "DICOM" format. The three-dimensional coordinates of the image are automatically generated. The three-dimensional coordinates of the image are determined, and "Render" is clicked to adjust the contrast. The maxilla and maxillary dentition are separated by appropriate threshold units for three-dimensional reconstruction. The three-dimensional models before and after treatment are cut, and the jaw and teeth are cut into separate parts. The original coordinates of the maxilla and dentition before treatment are fixed, and the maxilla and dentition after treatment are grouped so that the dentition after treatment can follow the overall movement of the maxilla after treatment. The landmark points of the entire skull base plane before and after treatment [skull base point (Ba), nasion point (N), bilateral supraorbital notch (UOrN), bilateral infraorbital margin midpoint (O)] are selected to determine the standard plane ( Figure 2 ), after the CBCT data models to be compared were preliminarily overlapped using the standard plane as the reference plane, the computer automatically overlapped the jaws before and after treatment, with 20,000 overlapping points. The calculation was repeated three times to improve the registration accuracy, so that the jaws and dentition after treatment were completely overlapped with the jaws before treatment. The overlapping models of the right maxillary posterior impacted teeth 16 and 17 were separated, and the buccal root apex and palatal root apex of 16 and 17 were marked before and after treatment, and the three-dimensional movement distance of the same marked point on the XYZ axis before and after treatment was measured ( Figure 3 All values were measured three times and the average value was taken to measure the three-dimensional movement distances of the affected teeth 16 and 17 in the vertical, horizontal and lateral directions.

[0069] Example 2: The patient in this example was an adolescent with an open bite of the anterior teeth. He was at the peak of his growth and development. To observe the influence of growth and development on the open bite of his dentition, CBCT data of the patient was collected during the 3-year observation and treatment period. After the 3D model of the jaw and dentition was built and overlapped, the crown and root parts were separated to observe the changes in the dentition. The final results showed that the open bite of the anterior teeth increased significantly with age ( Figure 4 ).

[0070] Example 3: This example is a patient with Angle Class II, Division 2, and maxillary protrusion. After treatment, the patient's anterior teeth were retracted and the facial shape improved. CBCT data of the patient before and after treatment were collected, and a three-dimensional model of the jaw and dentition was built and overlapped to separate the jaw and parts. The final overlap result showed that the patient's maxillary anterior teeth were significantly depressed and retracted, and the maxillary bone was also remodeled. Among them, the alveolar seat point (point A) was used as a landmark point for measurement and it was found that the landmark point was moved back about 3mm ( Figure 5 、 Figure 6 ).

[0071] This patent provides a three-dimensional measurement method for the skull, jaw, and teeth at different stages for every patient requiring orthodontic treatment. This method effectively overcomes the shortcomings of traditional two-dimensional cephalometric methods and further refines and optimizes existing three-dimensional directional overlap measurement methods. This measurement method can provide an intuitive and visual diagnostic and process monitoring tool for clinical orthodontic practice, and also offers a feasible three-dimensional analysis method for evaluating postoperative mechanisms. It can also generate significant economic and social benefits, and has promising prospects for industrialization.

[0072] Compared with the prior art, the present invention has the following beneficial effects:

[0073] 1. It is difficult to directly measure tooth torsion, tilt angle, and three-dimensional movement distance inside the mouth or in a two-dimensional plane. The 3D overlay measurement method described in this technology allows these data to be measured outside the mouth by creating a 3D model of the target dentition and jaw, and completely overlaying the jaw and dentition in the same coordinate system.

[0074] 2. For impacted teeth, the tooth removal process is very slow. When the tooth movement is small, the tooth movement errors observed on panoramic and cephalometric radiographs are large. Using the three-dimensional overlay measurement technology described in this invention can more accurately measure the three-dimensional movement distance of the affected tooth, helping orthodontists better understand the treatment progress.

[0075] 3. The growth and rotation of the jaw affects both the torque of the teeth and the width of the dental arch. The three-dimensional overlapping measurement of jaw changes by the present invention can help predict the trend of jaw growth and development and formulate a more appropriate treatment plan.

[0076] 4. Arch expansion therapy is often necessary for cases of insufficient maxillary width, maxillary protrusion, and narrow dental arches. Three-dimensional overlapping measurements comparing arch width changes before and after arch expansion can help doctors assess the effectiveness of arch expansion. Furthermore, after rapid arch expansion opens the midpalatal suture, tension in the palatal soft tissue can cause a certain degree of recurrence. Comparative measurements can also be an effective way to monitor and maintain arch width.

[0077] 5. One of the purposes of orthodontic treatment is to eliminate pathological occlusal interference factors, re-establish occlusion and adapt the joints by changing the occlusal relationship. The three-dimensional overlapping measurement and comparative analysis of the morphological changes of the condyle and fossa can well show the remodeling of the condyle.

[0078] 6. Improve and optimize the existing 3D model overlapping technology, omitting the step of obtaining the oral scan model, making the operation easier and reducing the risk of infectious disease transmission.

[0079] like Figure 7 As shown, the present invention provides a three-dimensional tooth and facial bone overlap measurement device 300 with the entire skull base as the reference plane, comprising:

[0080] The data acquisition module 310 is used to acquire the before and after cone beam computed tomography (CBCT) data to be compared and convert the CBCT data format;

[0081] The model building module 320 is used to respectively build and compare three-dimensional models of the front and back teeth and the jaw, determine the coordinate system, mark the landmark points of the entire skull base plane to determine the standard skull base plane;

[0082] The measurement module 330 is used to overlap the CBCT data to be compared using the standard plane as the reference plane, identify and perform registration overlap and mark points, and measure the changes of teeth, alveolar bones and facial and maxillary bones in three dimensions.

[0083] In order to implement the embodiment, the present invention also proposes an electronic device, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute each step in the three-dimensional overlap measurement method of teeth and facial bones of the aforementioned technical solution.

[0084] like Figure 8As shown, a non-transitory computer-readable storage medium 800 includes a memory 810 of instructions and an interface 830. The instructions can be executed by a processor 820 based on the three-dimensional overlay measurement of teeth and facial bones to complete the method. Alternatively, the storage medium can be a non-transitory computer-readable storage medium, for example, a ROM, random access memory (RAM), CD-ROM, magnetic tape, floppy disk, optical data storage device, etc.

[0085] In order to implement the embodiment, the present invention further proposes a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the three-dimensional overlap measurement of teeth and facial bones as in the embodiment of the present invention is implemented.

[0086] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0087] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0088] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may be performed out of the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present invention pertain.

[0089] The logic and / or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing the logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (e.g., a computer-based system, a system including a processor, or other system that can fetch and execute instructions from an instruction execution system, apparatus, or device). For purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include the following: an electrical connection with one or more wires (electronic devices), a portable computer disk cartridge (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and programmable read-only memory (EPROM or flash memory), fiber optic devices, and a portable compact disc read-only memory (CDROM). Furthermore, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing it in another suitable manner if necessary, and then storing it in a computer memory.

[0090] It should be understood that various parts of the present invention can be implemented using hardware, software, firmware, or a combination thereof. In the embodiments described, multiple steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof can be used: a discrete logic circuit having logic gate circuits for implementing logic functions on data signals, an application-specific integrated circuit having suitable combinational logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0091] Those skilled in the art will understand that all or part of the steps of the method for implementing the embodiment can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiment.

[0092] In addition, the functional units in the various embodiments of the present invention may be integrated into a single processing module, or each unit may exist physically separately, or two or more units may be integrated into a single module. The integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0093] The storage medium mentioned above may be a read-only memory, a magnetic disk, or an optical disk, etc. Although the embodiments of the present invention have been shown and described above, it is understood that the embodiments are exemplary and are not to be construed as limiting the present invention. Those skilled in the art may make changes, modifications, substitutions, and variations to the embodiments within the scope of the present invention.

Claims

1. A three-dimensional overlapping measurement method of teeth and facial bones with the entire skull base as the reference plane, characterized in that: include: Acquire cone beam computed tomography (CBCT) data before and after the comparison and convert the CBCT data format; Build and compare the three-dimensional models of the front and back teeth and jaws, determine the coordinate system, mark the landmark points of the entire skull base plane to determine the standard skull base plane; The skull base point (Ba), nasion point (N), bilateral supraorbital notches (UOrN) of the whole skull base plane were marked, and the midpoint of the bilateral infraorbital margin (0) was used as a landmark point; The standard plane is determined by the landmark points, and the three-dimensional models of the teeth and jaws to be compared are preliminarily overlapped using the standard plane as a reference plane, and then automatically aligned and overlapped by a computer; Using the standard plane as the reference plane, the CBCT data to be compared are overlapped, identified and registered, and the changes in the teeth, alveolar bones, and facial bones in the three-dimensional direction are measured, including: By adjusting different colors and transparency, the three-dimensional models of teeth and jaws that need to be compared can be distinguished; Mark the measurement points in the three-dimensional direction of the teeth or jaws, and measure the three-dimensional movement position change of the same point on the overlapped model to obtain the movement distance of the teeth and jaws; Separate the overlapping model of the target tooth or jaw part and measure the rotation and axial inclination angles based on the long axis of the tooth. Measure the rotation angle of the maxilla based on the ANS-PNS and the rotation angle of the mandible based on the mandibular plane.

2. The three-dimensional overlapping measurement method of teeth and facial bones with the entire skull base as the reference plane according to claim 1 is characterized in that: The steps of creating and comparing three-dimensional models of the front and back teeth and jaws include: Obtain the target dentition and jaw data of the patient to be compared through CBCT scanning, and import the CBCT data into the modeling software in DICOM format: Generate the three-dimensional coordinates of the model, adjust the contrast of the model, separate the upper and lower jaws and upper and lower dentitions through threshold segmentation, and perform three-dimensional reconstruction; Use modeling software to cut the model, cut the jaw and teeth into separate parts, and create them into groups.

3. The three-dimensional overlapping measurement method of teeth and facial bones with the entire skull base as the reference plane according to claim 1 is characterized in that: The cone beam computed tomography (CBCT) data at least includes three-dimensional data of the position and morphological structure of the maxilla, mandible, alveolar bone dentition, tooth crowns, and tooth roots.

4. The three-dimensional overlapping measurement method of teeth and facial bones with the entire skull base as the reference plane according to claim 1, characterized in that: The measurement points of the marked teeth are the root apex or tooth cusp points of the target teeth before and after treatment, and the movement distances of the root apex and tooth cusp points along the X-axis, Y-axis, and Z-axis before and after orthodontic treatment are measured to quantify the three-dimensional movement of the teeth.

5. The three-dimensional overlapping measurement method of teeth and facial bones with the entire skull base as the reference plane according to claim 1 is characterized in that: The measurement points for marking the jaw bone are the upper alveolar seat point, the anterior nasal ridge point, the nasion point, and the infraorbital point. The movement distances of the same landmark points along the X-axis, Y-axis, and Z-axis before and after orthodontic treatment are measured to quantify the three-dimensional movement coordinate system of the jaw bone. The tooth rotation angle is the rotation angle of the tooth around the long axis of the tooth observed after overlapping the three-dimensional model. The mandibular rotation angle is the rotation angle of the maxilla around the ANS-PNS or the rotation angle of the mandibular around the mandibular plane observed after overlapping the three-dimensional models.

6. A three-dimensional overlapping measurement device for teeth and facial bones with the entire skull base as the reference plane, characterized in that: include: A data acquisition module, used to acquire cone beam computed tomography (CBCT) data before and after comparison and convert the CBCT data format; The model building module is used to build and compare the three-dimensional models of the front and back teeth and jaws, determine the coordinate system, mark the landmark points of the entire skull base plane to determine the standard skull base plane; The skull base point (Ba), nasion point (N), bilateral supraorbital notches (UOrN) of the whole skull base plane were marked, and the midpoint of the bilateral infraorbital margin (0) was used as a landmark point; The standard plane is determined by the landmark points, and the three-dimensional models of the teeth and jaws to be compared are preliminarily overlapped using the standard plane as a reference plane, and then automatically aligned and overlapped by a computer; The measurement module is used to overlap the CBCT data to be compared using a standard plane as a reference plane, identify and perform registration overlap and punctuation, and measure the changes in the teeth, alveolar bone, and facial and maxillary bones in three dimensions; it includes: By adjusting different colors and transparency, the three-dimensional models of teeth and jaws that need to be compared can be distinguished; Mark the measurement points in the three-dimensional direction of the teeth or jaws, and measure the three-dimensional movement position change of the same point on the overlapped model to obtain the movement distance of the teeth and jaws; Separate the overlapping model of the target tooth or jaw part and measure the rotation and axial inclination angles based on the long axis of the tooth. Measure the rotation angle of the maxilla based on the ANS-PNS and the rotation angle of the mandible based on the mandibular plane.

7. An electronic device comprising: At least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor so as to enable the at least one processor to perform the steps of the method according to any one of claims 1 to 5.

8. A non-transitory computer-readable storage medium storing computer instructions, wherein: The computer instructions are used to enable the computer to execute each step of the method according to any one of claims 1 to 5.

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