CN117379197A

CN117379197A - Tooth and dentition model generation method, scheme formulation method, equipment and medium

Info

Publication number: CN117379197A
Application number: CN202210770870.1A
Authority: CN
Inventors: 沈斌杰; 姚峻峰
Original assignee: Shanghai Zhengya Dental Technology Co Ltd
Current assignee: Shanghai Zhengya Dental Technology Co Ltd
Priority date: 2022-06-30
Filing date: 2022-06-30
Publication date: 2024-01-12

Abstract

The embodiment of the invention relates to the field of medical equipment, and discloses a tooth and dentition model generation method, a scheme making method, equipment and a medium. The method comprises the steps of obtaining an actual crown model of a single tooth of a patient, and selecting a tooth form parameter model at a position corresponding to the actual crown model; the tooth form parameter model is obtained by analyzing teeth at the same position in a plurality of historical actual dentition models; adjusting morphological parameters in the tooth morphological parameter model to generate a tooth model so that a crown part in the generated tooth model is identical to the shape of an actual crown model; dividing root parts from the adjusted tooth models by taking the edge of the actual tooth crown model as a dividing reference, and taking the root parts as tooth root models to be spliced; and splicing the tooth root model to be spliced with the actual tooth crown model to obtain a target tooth model with tooth root information, so that the target tooth model is more close to the actual tooth condition of a patient.

Description

Tooth and dentition model generation method, scheme formulation method, equipment and medium

Technical Field

The embodiment of the invention relates to the field of medical equipment, in particular to a method for generating teeth and dentition models, a method for making a scheme, equipment and a medium.

Background

In recent years, with the continuous perfection and development of computer graphics and virtual reality simulation technologies, computer science and information technology are increasingly integrated with and interpenetrated with modern medicine and related technologies thereof. Meanwhile, with rapid development of computer software and hardware technology, image acquisition and processing technology, three-dimensional digital imaging technology and the like in the field of stomatology, computer technology has become an important component in stomatology education, clinic, scientific research and infrastructure. Orthodontic is used as a branch in the field of stomatology, mainly researches on the growth and development of three-dimensional structures of the jaw, the face and the cranium and deformities caused by various reasons, and the correction of the jaw deformities is facing a digital revolution nowadays, and particularly is widely applied to orthodontic diagnosis, design, treatment and curative effect prediction along with three-dimensional digital imaging and measuring technologies, so that the orthodontic is increasingly developed towards a computerized direction and has good development prospect.

At present, when a patient needs to correct teeth, the design of a correction scheme is needed by referring to tooth root information, otherwise, the correction scheme is inaccurate, for example, the tooth root of the patient exposes gums after correction, or the tooth crown part is excessively corrected to cause cracks and the like on the surface of the teeth of the patient, so that the correction effect is poor. The existing method for acquiring the oral cavity data of the patient during correction comprises the following steps:

(1) Tooth information is extracted by means of Cone Beam CT (CBCT) so as to judge the tooth condition of a patient according to the tooth information conveniently, and then a corresponding correction scheme is formulated. However, the resolution of the extracted dental image by using the CBCT method is low, the information contained in the dental image is rough, the details of the teeth of the patient cannot be obtained from the extracted dental information, and then the correction design and movement scheme of the teeth cannot be completed according to the information provided by the dental image extracted by using the CBCT method.

(2) The detailed information of the teeth of the patient is obtained by means of oral scanning, but the same defects exist by means of oral scanning, only the crown information of the patient can be obtained, and the root information of the patient cannot be obtained. In this way, the patient's crown information is typically concatenated with the root information of the standard tooth model to obtain a patient's dentition model with the root information. However, the above-mentioned root information using the standard tooth model has a certain limitation as the root information of all patients, and the actual root situation of each patient cannot be reflected in a personalized manner, so that the correction scheme formulated according to the spliced dentition model cannot conform to the actual tooth situation of each patient, and the accuracy of the correction scheme design is affected.

Disclosure of Invention

The embodiment of the invention aims to provide a method, a scheme making method, equipment and a medium for generating a tooth and dentition model, so that the generated tooth model with tooth root information contains detail information of the tooth and is more close to the actual tooth condition of a patient.

In order to solve the above technical problems, an embodiment of the present invention provides a method for generating a tooth model with root information, including: acquiring an actual crown model of a single tooth of a patient, and selecting a tooth form parameter model at a position corresponding to the actual crown model; the tooth form parameter model is obtained by analyzing teeth at the same position in a plurality of historical actual dentition models, and comprises a plurality of form parameters representing the shape characteristics of the teeth; adjusting morphological parameters in the tooth morphological parameter model to generate a tooth model so that a crown part in the generated tooth model is identical to the shape of an actual crown model; dividing root parts from the adjusted tooth models by taking the edge of the actual tooth crown model as a dividing reference, and taking the root parts as tooth root models to be spliced; and splicing the tooth root model to be spliced with the actual tooth crown model to obtain a target tooth model with tooth root information.

The embodiment of the invention also provides a generating method of the dentition model with the tooth root information, which comprises the following steps: according to the method for generating the tooth model, generating tooth models with tooth root information corresponding to all single teeth of a patient; and arranging the tooth models according to the tooth positions to obtain a dentition model with tooth root information.

The embodiment of the invention also provides a method for making the tooth correction scheme, which comprises the following steps: obtaining a dentition model of a patient according to the generating method of the dentition model with the tooth root information; designing a target correction position of each tooth according to the crown characteristic information and the root characteristic information of each tooth in the dentition model; a dental appliance plan for the patient is determined based on the target appliance locations for all teeth.

The embodiment of the invention also provides electronic equipment, which comprises: at least one processor; and a memory communicatively coupled to the at least one processor; the memory stores instructions executable by the at least one processor to enable the at least one processor to perform the method of generating a dental model with root information or the method of creating a dental appliance.

The embodiment of the invention also provides a computer readable storage medium, which stores a computer program, wherein the computer program realizes the generation method of the tooth model with the tooth root information or realizes the generation method of the tooth column model with the tooth root information or realizes the formulation method of the tooth correction scheme when being executed by a processor.

Compared with the prior art, the embodiment of the invention obtains the actual crown model of a single tooth of a patient, selects the tooth form parameter model corresponding to the actual crown model, adjusts the form parameters in the tooth form parameter model according to the actual crown model, generates the tooth model, generates the crown part in the tooth model which is the same as the actual crown model in shape, takes the edge of the actual crown model as a segmentation reference, segments out the root part in the tooth model as the root model to be spliced, and then splices the actual crown part and the generated root part to be spliced to obtain the complete tooth model. The morphological characteristics of the teeth are represented by the morphological parameter model, and when the morphological parameters in the morphological parameter model are changed, the corresponding morphology of the teeth is changed, and the personalized tooth shape can be generated. In addition, since the tooth form parameter model is obtained according to the tooth analysis of the same position in the historical actual dentition model obtained by a plurality of historical cases, the adjusted tooth form parameter model can be personalized to reflect the tooth root shape closer to the actual condition of the patient by adjusting the form parameters of the tooth form parameter model representing the tooth shape characteristics. Therefore, the tooth root model to be spliced which is segmented from the teeth in the embodiment of the invention better accords with the actual tooth root condition of a patient, so that the spliced target tooth model with the tooth root information better accords with the actual tooth condition of the patient, thereby providing more accurate and complete tooth shape information for doctors and improving the accuracy of an correction scheme designed based on the target tooth model.

In addition, the same manner of determining the crown portion of the tooth form parameter model as the shape of the actual crown model includes: calculating the distance between each vertex on the actual crown model and the corresponding vertex on the tooth form parameter model; determining whether the crown part of the tooth form parameter model is identical to the shape of the actual crown model according to the calculated distance.

In addition, determining whether the crown portion of the tooth form parameter model is identical to the shape of the actual crown model based on the calculated distance includes: determining that the crown part of the tooth form parameter model is identical to the actual crown model in shape when the calculated average value of the distances between each vertex on the actual crown model and the corresponding vertex on the tooth form parameter model is smaller than a first distance threshold;

or determining that the crown portion of the tooth form parameter model is identical to the shape of the actual crown model when the sum of the calculated distances of all the vertices on the actual crown model and the corresponding vertices on the tooth form parameter model is less than a second distance threshold;

or determining that the crown portion of the tooth form parameter model is identical to the shape of the actual crown model when the sum of squares of distances between all vertices on the calculated actual crown model and corresponding vertices on the tooth form parameter model is less than a third distance threshold;

Alternatively, when the calculated maximum distance between each vertex on the actual crown model and the corresponding vertex on the tooth form parameter model is smaller than the fourth distance threshold, it is determined that the crown portion of the tooth form parameter model is identical to the actual crown model in shape.

In addition, the corresponding vertices on the tooth form parameter model are: a vertex closest to the vertex on the actual crown model on the tooth morphology parameter model; or is: the vertices on the actual crown model are projected in the normal direction thereof to form projected points on the tooth morphological parameter model.

In addition, adjusting morphological parameters in the tooth morphological parameter model to generate a tooth model such that a crown portion in the generated tooth model is identical to a shape of an actual crown model, comprising: and adjusting at least one morphological parameter of the tooth morphological parameter model each time by a preset step length, and judging whether the shape of the crown part of the tooth morphological parameter model is the same as that of the actual crown model after each adjustment until the crown part of the tooth morphological parameter model is determined to be the same as that of the actual crown model.

In addition, when one morphological parameter is adjusted each time, the morphological parameter which is adjusted each time is the morphological parameter which has the greatest influence on the shape proximity degree of the tooth morphological parameter model and the actual crown model in all the morphological parameters, so that the adjustment times of the morphological parameters are reduced, and the adjustment efficiency is improved.

In addition, the method for dividing a root portion from a tooth model with an edge of an actual crown model as a division reference includes: projecting the edge line of the actual crown model in a direction towards the tooth morphological parameter model, and taking a projection curve formed on the tooth morphological parameter model as a dividing line; the tooth morphological parameter model is separated into a crown portion and a root portion according to the parting line.

In addition, the method for dividing a root portion from a tooth model with an edge of an actual crown model as a division reference includes: fitting and dividing the curved surface according to the edge line of the actual dental crown model; the tooth morphological parameter model is separated into a crown portion and a root portion by using the segmentation curved surface.

In addition, the method for splicing the tooth root model to be spliced with the actual tooth crown model comprises the following steps: orderly stitching the edge line vertexes of the tooth root models to be spliced and the edge line vertexes of the actual tooth crown models to form a triangular network surface patch so as to splice the tooth root models to be spliced and the actual tooth crown models.

In addition, after orderly stitching the edge line vertex of the tooth root model to be spliced and the edge line vertex of the actual tooth crown model to form the triangular network patch, the method further comprises the steps of: determining grids within a preset distance from the edge of the stitching part; the mesh is smoothed to smooth the stitching of the target tooth model.

In the step of selecting the tooth form parameter model at the position corresponding to the actual crown model, the step of: determining a corresponding position according to the tooth number; alternatively, the corresponding position is determined based on the tooth type.

In addition, the tooth morphology parameter model is obtained by analyzing teeth at the same position in a plurality of historical actual dentition models, and comprises: respectively deforming the tooth standard model at the same position as the tooth morphological parameter model until the tooth standard model is the same as the shape of each historical actual dentition model, so as to obtain a plurality of deformed tooth standard models; and analyzing the deformed tooth standard models to obtain a tooth morphological parameter model. And the data of a plurality of historical actual dentition models for analyzing and obtaining the tooth form parameter model are subjected to unified processing by utilizing the tooth standard model, so that the subsequent data analysis is convenient.

Before deforming the tooth standard model at the same position as the tooth morphological parameter model, the method further comprises: aligning the tooth standard model with the teeth at the same position in the historical actual dentition model; the alignment method comprises the following steps: alignment according to a coordinate system and/or feature point alignment.

In addition, the coordinate system alignment includes alignment according to coordinate system information including: taking any position of the center of gravity of the single tooth, the midpoint of the gum line of the single tooth, the impedance center point of the single tooth moving and the cusp of the root of the single tooth as the origin of a coordinate system; the direction of the tooth axis is taken as the Z-axis direction, the connecting line direction of the labial side and the lingual side is taken as the Y-axis direction, and the X-axis direction is determined according to the Y-axis direction and the Z-axis direction, wherein the X-axis direction is perpendicular to the Y-axis direction and the Z-axis direction respectively.

In addition, feature point alignment includes: aligning according to the characteristic point information; if the tooth type of the tooth standard model is incisor or cuspid, the feature point information includes: mesial and distal to the incisal margin of the tooth; if the tooth type of the tooth standard model is premolars, the feature point information includes: lingual bumps and labial bumps; if the tooth type of the tooth standard model is post-molar, the feature point information includes: a bump in the lingual proximal direction, a bump in the labial proximal direction, a bump in the lingual distal direction, and a bump in the labial distal direction.

In addition, the tooth morphology parameter model is obtained by analyzing the teeth at the same position in the plurality of historical actual dentition models, and the tooth morphology parameter model comprises the following steps: analyzing teeth at the same position in a plurality of historical actual dentition models by adopting a principal component analysis method to obtain a position average value of vertexes of the same serial number in each model and a characteristic vector for representing tooth morphology; and calculating according to the position average value and the feature vector to obtain the tooth morphology parameter model.

In addition, before analyzing teeth at the same position in a plurality of historical actual dentition models by adopting a principal component analysis method, the method comprises the following steps: the resolution and vertex sequence numbers of the plurality of historical actual dentition models are unified.

In addition, the method for obtaining the tooth form parameter model by analyzing the plurality of deformed tooth standard models comprises the following steps: analyzing the vertexes of the deformed tooth standard models by adopting a principal component analysis method to obtain the position average value of the vertexes of the same serial number and the characteristic vector for representing the tooth morphology; and calculating according to the position average value and the feature vector to obtain the tooth morphology parameter model.

Additionally, acquiring an actual crown model of a single tooth of a patient, comprising: obtaining an actual dentition model of a patient through oral scanning; and dividing the actual dentition model to obtain an actual crown model of the single tooth.

In addition, after arranging each tooth model according to the tooth position, it further includes: judging whether two tooth roots collide with each other in the tooth column model with tooth root information; if present, the root portions of the two tooth models that collide with each other are deformed to eliminate the collision.

In addition, judging whether there are two tooth models in which roots collide with each other in a dentition model with root information, comprising: obtaining a detection plane between two adjacent tooth models, wherein the detection plane is as follows: taking the direction of the connecting line of the centers of gravity of two adjacent tooth models as the normal direction of the detection plane, and establishing a plane through the midpoint of the connecting line of the centers of gravity; if both of the two adjacent tooth models do not pass through the detection plane, the two adjacent tooth models do not collide with each other; if at least one of the two adjacent tooth models passes through the detection plane, the two adjacent tooth models collide with each other.

In addition, deforming root portions of two tooth models that collide with each other to eliminate the collision, comprising: acquiring a reference plane between two mutually collided tooth models, wherein the reference plane is a plane established by taking the direction of the connecting line of the centers of gravity of two adjacent tooth models as the normal direction of the reference plane and passing through the midpoint of the connecting line of the centers of gravity; determining a maximum depth of intersection between a root portion of the tooth model passing through the reference plane and the reference plane, and a root apex corresponding to the maximum depth of intersection; determining a projection point of the root vertex on a reference plane in the direction of the intersecting depth as a moving target point; the deformation operation is performed on the root portion of the tooth model passing through the reference plane without moving the crown portion of the tooth model passing through the reference plane so that the position of the root apex is moved to the movement target point, eliminating the collision.

Drawings

One or more embodiments are illustrated by way of example and not limitation in the figures of the accompanying drawings, in which like references indicate similar elements, and in which the figures of the drawings are not to be taken in a limiting sense, unless otherwise indicated.

FIG. 1 is a flow chart of a method of generating a tooth model with root information in accordance with an embodiment of the present invention;

FIG. 2 is a schematic diagram of the structure of an actual dentition model obtained by oral scanning in accordance with an embodiment of the present invention;

FIG. 3 is a schematic view of the structure of an actual crown model of a single tooth in accordance with an embodiment of the present invention;

FIG. 4 is a flow chart of a manner of determining that a crown portion of a tooth form parameter model is the same shape as an actual crown model in accordance with an embodiment of the present invention;

FIG. 5 is a schematic view of a division line determined in a projection manner for root portion division according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of a division line determined in a manner of fitting a division curved surface for root portion division according to an embodiment of the present invention;

FIG. 7 is a flow chart of a fairing process for a splice location in accordance with an embodiment of the invention;

FIG. 8 is a schematic view of a tooth model after a fairing process in accordance with an embodiment of the invention;

FIG. 9 is a flow chart of a method of generating a dentition model with root information according to an embodiment of the present invention;

FIG. 10 is a flowchart for determining whether a collision between teeth occurs according to an embodiment of the present invention;

FIG. 11 is a schematic view of a tooth model with root information after collision elimination in accordance with an embodiment of the invention;

FIG. 12 is a flow chart of a method of formulating a dental appliance in accordance with an embodiment of the present invention;

fig. 13 is a schematic structural diagram of an electronic device according to an embodiment of the present invention.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, those of ordinary skill in the art will understand that in various embodiments of the present invention, numerous technical details have been set forth in order to provide a better understanding of the present application. However, the technical solutions claimed in the present application can be implemented without these technical details and with various changes and modifications based on the following embodiments.

The following embodiments are divided for convenience of description, and should not be construed as limiting the specific implementation of the present invention, and the embodiments can be mutually combined and referred to without contradiction.

A first embodiment of the present invention relates to a method for generating a tooth model with root information, and the specific flow is shown in fig. 1, including:

step 101, acquiring an actual crown model of a single tooth of a patient, and selecting a tooth form parameter model at a position corresponding to the actual crown model. Wherein the tooth form parameter model is obtained by analyzing teeth at the same position in a plurality of historical actual dentition models, and the tooth form parameter model comprises a plurality of form parameters representing tooth shape characteristics.

Step 102, adjusting morphological parameters in the tooth morphological parameter model, generating a tooth model so that a crown part in the generated tooth model is identical to the shape of the actual crown model.

Step 103, dividing the root part from the adjusted tooth model by taking the edge of the actual crown model as a dividing reference, and taking the root part as a tooth root model to be spliced; and splicing the tooth root model to be spliced with the actual tooth crown model to obtain a target tooth model with tooth root information.

Implementation details of embodiments of the present application are specifically described below, and the following details are provided for easy understanding only, and are not necessary for implementing the present embodiment.

Wherein, in step 101, an actual crown model of a single tooth of the patient is obtained, specifically, an actual dentition model 1 of the patient shown in fig. 2 is obtained by means of oral scanning, wherein, the actual dentition model 1 only comprises a crown part of the tooth of the patient. The actual dentition model 1 is divided to obtain an actual crown model 11 of a single tooth as shown in fig. 3.

Step 101, selecting a tooth form parameter model at a position corresponding to an actual crown model, wherein the corresponding position can be determined according to a tooth number; alternatively, the corresponding position is determined based on the tooth type. When determining the corresponding position according to the tooth number, different numbers can be set for each tooth in the dentition, and the teeth at the same position in the actual crown model and the tooth morphological parameter model are determined according to the same numbers. The dentition may be numbered using numerical labeling (FDI) when each tooth in the dentition is provided with a different number. In determining the corresponding positions according to the tooth types, the teeth may be classified into incisors, cuspids, premolars, and postmolar teeth according to the tooth types of the actual crown models, and the tooth morphological parameter models of the same tooth types may be selected.

In addition, the tooth form parameter model is obtained by analyzing the teeth at the same position in the plurality of historical actual dentition models, and particularly when the teeth at the same position are determined according to the tooth numbers, the tooth form parameter model is obtained by analyzing the teeth with the same number in the plurality of historical actual dentition models; in determining the teeth at the same location based on the tooth type, a tooth morphology parameter model is obtained by analyzing the teeth of the same tooth type in a plurality of historical actual dentition models. The historical actual dentition model can be a tooth model generated according to complete tooth data obtained by CBCT, and comprises a dental crown part and a dental root part, wherein the dental crown part is required to carry out relevant design of medical correction, so that the pixel requirement is higher and can not be used, but the dental root data only has an auxiliary effect when the correction scheme is designed, so that the pixel requirement is lower, and the pixels of the CBCT are enough. The plurality of historical actual dentition models can be prefabricated dentition model databases, and dentition models of various crowds are prestored.

Specifically, in one embodiment, a principal component analysis method may be used to analyze teeth at the same position in a plurality of historical actual dentition models, so as to obtain a position average value of vertices of the same serial number in each model and a feature vector for representing tooth morphology; and calculating according to the position average value and the feature vector to obtain the tooth morphology parameter model. Principal component analysis is to try to replace the original index by recombining a plurality of original comprehensive indexes with certain relativity into a new independent index. In this example, the principal component analysis method is used to represent the shape of different teeth by means of a position average and a feature vector representing the tooth morphology.

In one embodiment, the position average of the vertices of the same serial number in each model is obtained using principal component analysisAnd after feature vectors for characterizing tooth morphology, ordering the feature vectors from large to small in feature values to obtain a sequence of feature vectors T1, T2, T3. The tooth morphology parameter model can be expressed as a linear combination of these feature vectors and the position average t:

wherein T represents a tooth morphological parameter model, alpha i represents a morphological parameter corresponding to the ith feature vector, T _i Representing the ith feature vector, i is a natural number greater than 0. In practical application, all feature vectors can be selected to generate a tooth form parameter model according to the feature vectors which can more highlight the personalized information of the teeth, and the selection rule can be to select the corresponding feature vector with the sum of the feature values accounting for 95% of the sum of all the feature values.

Before the principal component analysis method is adopted to analyze teeth at the same position in the plurality of historical actual dentition models, the resolution and the vertex serial numbers of the plurality of historical actual dentition models can be unified, and the unified plurality of teeth are utilized to conduct principal component analysis, so that the correlation among analysis data is facilitated, and further the calculation is facilitated to obtain the tooth morphological parameter model. When the principal component analysis is used for calculation, the tooth form parameter model can be obtained through calculation in the manner described above, and details are not repeated here.

In one embodiment, the way to unify the resolution and vertex sequence numbers of a plurality of historical actual dentition models includes: and respectively deforming the tooth standard model at the same position as the tooth morphological parameter model until the tooth standard model is the same as the shape of each historical actual dentition model, so as to obtain a plurality of deformed tooth standard models. During deformation, the closest point on the tooth at the same position in the historical actual dentition model can be searched according to each vertex on the tooth standard model, the vertex on the tooth standard model is moved to the closest point, and the intersection point of each vertex on the tooth standard model projected along the normal direction of the vertex and the tooth at the same position in the historical actual dentition model can be calculated, and the vertex on the tooth standard model is moved to the intersection point, so that the deformation operation is completed. The judging mode of whether the tooth shapes are the same comprises the following steps: if the deformed tooth standard model is overlapped with each vertex position of the tooth at the same position in the historical actual dentition model, the two teeth have the same shape.

Before the standard tooth model at the same position as the tooth form parameter model is deformed respectively, the standard tooth model can be aligned with the teeth at the same position in the historical actual dentition model, so that the distance that each vertex needs to move in the subsequent deformation operation is reduced. The alignment operation may be alignment according to the coordinate system information, or alignment according to the feature point information, or alignment according to the coordinate system, and then aligning the feature points of the two teeth aligned by the coordinate system, so as to improve alignment accuracy. The coordinate system information includes: taking any position of the center of gravity of the single tooth, the midpoint of the gum line of the single tooth, the impedance center point of the single tooth moving and the cusp of the root of the single tooth as the origin of a coordinate system; the direction of the tooth axis is taken as the Z-axis direction, the connecting line direction of the labial side and the lingual side is taken as the Y-axis direction, and the X-axis direction is determined according to the Y-axis direction and the Z-axis direction, wherein the X-axis direction is perpendicular to the Y-axis direction and the Z-axis direction respectively. The feature point information may be set differently according to the tooth type, for example, if the tooth type of the tooth standard model is incisors or cuspids, the feature point information includes: mesial and distal to the incisal margin of the tooth; if the tooth type of the tooth standard model is premolars, the feature point information includes: lingual bumps and labial bumps; if the tooth type of the tooth standard model is post-molar, the feature point information includes: a bump in the lingual proximal direction, a bump in the labial proximal direction, a bump in the lingual distal direction, and a bump in the labial distal direction. When alignment is performed according to the feature point information, whether alignment operation is completed can be judged by judging the spatial distance between the corresponding feature points of the two teeth, for example, the sum of the spatial distances between all the corresponding feature points between the two teeth can be calculated, and if the calculated sum of the spatial distances is smaller than a threshold value, the completion of the feature point alignment operation is determined. The above description of the coordinate system information and the feature point information is only for convenience in understanding the embodiment, and the coordinate system information and the feature point information are not limited to the above-described information at the time of actual application. After the alignment operation, a deforming operation is performed on the basis of the two aligned teeth to change the shape of the tooth standard model so that the deformed tooth standard model is identical to the shape of the teeth at the same position in the historic actual dentition model. In the deformation process, each vertex on the aligned tooth standard model can be searched for the closest point on the tooth at the same position in the historical actual dentition model, the vertex on the tooth standard model is moved to the closest point, and the intersection point of each vertex on the aligned tooth standard model, which is projected along the normal direction of the vertex and is positioned on the tooth at the same position in the historical actual dentition model, can be calculated, and the vertex on the tooth standard model is moved to the intersection point, so that the deformation operation is completed.

Wherein, in step 102, the morphological parameters in the tooth morphological parameter model are adjusted, and the tooth model is generated, so that the crown portion in the generated tooth model has the same shape as the actual crown model, which includes: and adjusting at least one morphological parameter of the tooth morphological parameter model each time by a preset step length, and judging whether the shape of the crown part of the tooth morphological parameter model is the same as that of the actual crown model after each adjustment until the crown part of the tooth morphological parameter model is determined to be the same as that of the actual crown model.

When the morphological parameters are adjusted, a preset step size (0.1 mm is assumed) can be set, and the initial morphological parameters { α } are set, wherein the number of the morphological parameters is the same as the number of the feature vectors, and all the values of the initial morphological parameters are 0. Only one of the adjusting coefficients can be adjusted when the morphological parameters are adjusted each time, the morphological parameters adjusted each time are the morphological parameters with the greatest influence on the shape proximity degree of the tooth morphological parameter model and the actual dental crown model in all the morphological parameters, and after the preset step length is adjusted, compared with the preset step length is adjusted by other morphological parameters, the morphological parameters with the greatest influence on the shape proximity degree of the tooth morphological parameter model and the actual dental crown model are higher in degree. The morphological parameters with the greatest influence on the shape proximity can be determined in particular by: when the shape parameters of the tooth shape parameter model are the same, each shape parameter is adjusted by a preset step length, the corresponding shape proximity degree is calculated after each shape parameter is adjusted, the number of the shape parameters is 3 as an example, on the basis of the shape parameters {0, 0}, three shape parameters are respectively adjusted according to the step length of 0.1mm to obtain {0.1,0,0}, {0,0.1,0}, {0,0,0.1}, the distances between the crown part of the tooth shape parameter model and the corresponding vertexes of the actual crown model under the three different shape parameters are calculated respectively, for example, the average value of the distances between the corresponding vertexes of the two models can be calculated, or the sum of the squares of the distances between the corresponding vertexes can be calculated, the influence of the shape proximity degree on the model is determined according to the distance between the corresponding vertexes, wherein the smaller the distance between the corresponding vertexes is the larger the two models, and the adjusted parameters are the shape proximity degree with the largest influence. The number of times of adjustment of the morphological parameters can be reduced by such an adjustment method. When the morphological parameters are adjusted, each morphological parameter can be adjusted in turn according to a preset sequence. Or more than one morphological parameter may be adjusted at each adjustment, etc.

The step 102 of determining the crown portion of the tooth form parameter model in the same manner as the shape of the actual crown model, specifically as shown in fig. 4, includes:

step 1021, calculating the distance between each vertex on the actual crown model and the corresponding vertex on the tooth form parameter model.

Step 1022, determining whether the crown portion of the tooth form parameter model is identical to the shape of the actual crown model according to the calculated distance. In practical applications, the shapes may be identical, or the shapes may be within an acceptable error range.

Specifically, when calculating the distance between each vertex on the actual crown model and the corresponding vertex on the tooth form parameter model, one vertex can be selected on the actual crown model, the vertex closest to the vertex on the actual crown model can be found on the tooth form parameter model, and the spatial distance between the two vertices can be calculated. Or selecting one vertex from the actual crown model, projecting the vertex of the actual crown model on the normal direction of the vertex to form an intersection point of the tooth morphological parameter model as a corresponding vertex on the tooth morphological parameter model, and calculating the space distance between the two vertices. The spatial distance between two vertices may be calculated from the spatial coordinates of the two vertices. After calculating the spatial distance between the corresponding vertexes of the two models, the average value of the distance, the sum of the distances or the square sum of the distances between the corresponding vertexes can be calculated based on the spatial distance, and whether the crown part of the tooth form parameter model is identical to the shape of the actual crown model is determined according to the calculated average value of the distance, the sum of the distances or the square sum of the distances. The smaller the calculated average value of the distances, the sum of the distances, or the sum of the squares of the distances, the closer the crown portion of the tooth morphology parameter model is to the same shape as the actual crown model. When the calculated average value of the distances, the sum of the distances, or the sum of the squares of the distances is small to some extent, the crown portion of the tooth form parameter model can be approximately regarded as the same shape as the actual crown model, for example, when the calculated average value of the distances of each vertex on the actual crown model and the corresponding vertex on the tooth form parameter model is smaller than a first distance threshold value, the crown portion of the tooth form parameter model is determined to be the same shape as the actual crown model; or determining that the crown portion of the tooth form parameter model is identical to the shape of the actual crown model when the sum of the calculated distances of all the vertices on the actual crown model and the corresponding vertices on the tooth form parameter model is less than a second distance threshold; or determining that the crown portion of the tooth form parameter model is identical to the shape of the actual crown model when the sum of squares of distances between all vertices on the calculated actual crown model and corresponding vertices on the tooth form parameter model is less than a third distance threshold; alternatively, when the calculated maximum distance between each vertex on the actual crown model and the corresponding vertex on the tooth form parameter model is smaller than the fourth distance threshold, it is determined that the crown portion of the tooth form parameter model is identical to the actual crown model in shape. For convenience of understanding, taking as an example that the crown portion of the tooth form parametric model is determined to be identical to the shape of the actual crown model when the average value of the distances of the corresponding vertices is smaller than the first distance threshold, first, each vertex of the actual crown model and the corresponding vertex of each vertex on the tooth form parametric model are determined by the above-described manner of confirming the corresponding vertex. And secondly, calculating the space distance between each pair of vertexes according to the space coordinates of the vertexes, and calculating the average value of all calculated space distances after all vertexes of the actual dental crown model calculate the space distances between the vertexes corresponding to the vertexes. Finally, comparing the calculated size relation between the average value of the space distance and the first distance threshold value, if the average value of the distance is smaller than the first distance threshold value, the shape of the dental crown part of the dental morphology parameter model is the same as that of the actual dental crown model, and taking the dental morphology parameter model at the moment as a dental model for carrying out tooth root part segmentation subsequently; if the average value of the distances is larger than or equal to the first distance threshold value, the shapes of the crown part of the tooth form parameter model and the actual crown model are different, the tooth form parameter model is continuously adjusted, whether the shapes of the crown part of the tooth form parameter model and the actual crown model are the same is judged again after adjustment until the average value of the distances is smaller than the first distance threshold value, and the adjustment of the tooth form parameter model is completed. The vertexes of the model are vertexes of triangular patches or tetragonal patches in the model.

In step 103, the edge of the actual crown model is used as a segmentation reference, and the root part is segmented from the adjusted tooth model, and the root model to be spliced at least comprises the following two embodiments:

in one embodiment, as shown in fig. 5, the edge line of the actual crown model is projected in a direction toward the tooth form parameter model, and a projection curve 31 formed on the tooth form parameter model is set as a dividing line; the tooth form parameter model 2 is separated into a crown portion 21 and a root portion 22 according to the parting line.

In another embodiment, as shown in FIG. 6, the surface 32 is segmented according to an edge line fit of an actual crown model; the tooth form parameter model 2 is separated into a crown portion 21 and a root portion 22 by the partition curved surface 3.

Step 103, splicing the tooth root model to be spliced with the actual tooth crown model to obtain a target tooth model with tooth root information, wherein the step comprises the following steps: orderly stitching the edge line vertexes of the tooth root models to be spliced and the edge line vertexes of the actual tooth crown models to form a triangular network surface patch so as to splice the tooth root models to be spliced and the actual tooth crown models.

After the root model to be spliced is spliced with the actual crown model, a fairing process may also be performed on the spliced position, where a specific flow is shown in fig. 7, and includes:

Step 1031, determining a grid within a predetermined distance from the edge of the seam.

Step 1032, smoothing the mesh to smooth the stitching of the target tooth model. The tooth model 4 after the fairing treatment is shown in fig. 8.

The solutions described in the above embodiments can obtain the target tooth that contains tooth root information and meets the actual tooth situation of the patient, and then can generate the dentition model of the patient based on the target tooth, or design the orthodontic solution of the tooth for the user based on the target tooth, etc.

The above steps of the methods are divided, for clarity of description, and may be combined into one step or split into multiple steps when implemented, so long as they include the same logic relationship, and they are all within the protection scope of this patent; it is within the scope of this patent to add insignificant modifications to the algorithm or flow or introduce insignificant designs, but not to alter the core design of its algorithm and flow.

The embodiment of the invention relates to a generating method of a dentition model with tooth root information, as shown in fig. 9, comprising the following steps:

step 901, generating tooth models with tooth root information corresponding to all single teeth of a patient according to the above generation method of the tooth models;

Step 902, arranging each tooth model according to the tooth position to obtain a dentition model with tooth root information.

Compared with the prior art, the embodiment of the invention has the advantages that after the tooth model with the tooth root information which accords with the actual tooth condition of a patient is generated, all the generated tooth models are arranged according to the tooth sequence to obtain the tooth model with the tooth root information, and the obtained tooth model also accords with the actual tooth condition of the patient, so that the accuracy of the correction scheme designed based on the tooth model can be improved.

After each tooth model is arranged according to the tooth positions in step 902, it may further be determined whether collision occurs between teeth, as shown in fig. 10, including:

step 1001, judging whether two tooth roots collide with each other exist in a tooth column model with tooth root information;

if yes, go to step 1002 to deform the tooth root portions of the two tooth models that collide with each other to eliminate the collision; and re-enter step 1001 to make a determination after the collision is eliminated.

If the determination result is negative, the process proceeds to step 1003, where a dentition model with root information is obtained.

When judging whether two tooth models with tooth root information exist in the tooth column model with the tooth root collision, acquiring a detection plane between two adjacent tooth models, wherein one setting rule of the detection plane is as follows: taking the direction of the connecting line of the centers of gravity of two adjacent tooth models as the normal direction of the detection plane, and establishing a plane through the midpoint of the connecting line of the centers of gravity; if both of the two adjacent tooth models do not pass through the detection plane, the two adjacent tooth models do not collide with each other; if at least one of the two adjacent tooth models passes through the detection plane, the two adjacent tooth models collide with each other.

When deforming root portions of two tooth models that collide with each other to eliminate the collision, a reference plane between the two tooth models that collide with each other may be acquired, a maximum intersection depth between the root portion of the tooth model that passes through the reference plane and the reference plane, and a root apex corresponding to the maximum intersection depth are determined; determining a projection point of the root vertex on a reference plane in the direction of the intersecting depth as a moving target point; the deformation operation is performed on the root portion of the tooth model passing through the reference plane without moving the crown portion of the tooth model passing through the reference plane so that the position of the root apex is moved to the movement target point, eliminating the collision.

The method for obtaining the optimal solution of the tooth root moving position for eliminating the collision by the deformation mode is specifically as follows:

min|LX-LY| ²

s.t.

x _c ＝b ₁ ，

x _p ＝b ₂ ，

wherein LX is the post-deformation root apex position to be solved, LY is the pre-deformation root apex position, x _c And x _p Is a constraint condition, wherein x _c For the fixed point constraint, the crown apex position b1 is represented as fixed, x _p For the moving point constraint, the position of the root apex corresponding to the maximum intersection depth is updated to the moving target point b2, and the tooth model 5 with root information after the collision is eliminated is shown in fig. 11.

The embodiment of the invention relates to a method for making a dental correction scheme, as shown in fig. 12, comprising the following steps:

step 1201, obtaining a dentition model of a patient according to the generating method of the dentition model with tooth root information;

step 1202, designing a target correction position of each tooth according to the crown characteristic information and the root characteristic information of each tooth in the dentition model;

step 1203, determining a dental appliance for the patient based on the target appliance locations for all teeth.

Specifically, the root feature information at least includes: the initial position of the tooth root, the target correction position at least comprises: the correction position of the tooth root is designed according to the initial position of the tooth root, so that the change of the correction position of the tooth root relative to the initial position of the tooth root is in a preset range. The tooth correction scheme designed according to the tooth root information can take the limitation of the movement range of the tooth root into consideration, so that the problem that the tooth root exposes out of the gum after the tooth correction of a patient is carried out, or the tooth root cannot correspondingly move to cause tooth damage and the like due to overlarge movement of the crown part in the correction scheme is avoided, and the establishment of the tooth correction scheme is ensured to be more in accordance with the actual tooth condition of a user.

An embodiment of the invention relates to an electronic device, as shown in fig. 13, comprising at least one processor 1301; and a memory 1302 communicatively coupled to the at least one processor 1301; the memory 1302 stores instructions executable by the at least one processor 1301, where the instructions are executed by the at least one processor 1301 to enable the at least one processor 1301 to perform the method for generating a dental model with root information or the method for creating a dental appliance.

Where memory 1302 and processor 1301 are connected by a bus, the bus may comprise any number of interconnected buses and bridges, the buses connecting the various circuits of the one or more processors 1301 and memory 1302 together. The bus may also connect various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface between the bus and the transceiver. The transceiver may be one element or may be a plurality of elements, such as a plurality of receivers and transmitters, providing a means for communicating with various other apparatus over a transmission medium. The data processed by the processor is transmitted over a wireless medium via an antenna, which further receives the data and transmits the data to the processor 1301.

Processor 1301 is responsible for managing the bus and general processing and may provide various functions including timing, peripheral interfaces, voltage regulation, power management, and other control functions. And memory 1302 may be used to store data used by the processor in performing operations.

Embodiments of the present invention relate to a computer-readable storage medium storing a computer program. The computer program implements the above-described method embodiments when executed by a processor.

That is, it will be understood by those skilled in the art that all or part of the steps in implementing the methods of the embodiments described above may be implemented by a program stored in a storage medium, where the program includes several instructions for causing a device (which may be a single-chip microcomputer, a chip or the like) or a processor (processor) to perform all or part of the steps in the methods of the embodiments described herein. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a random access Memory (RAM, random Access Memory), a magnetic disk, or an optical disk, or other various media capable of storing program codes.

It will be understood by those of ordinary skill in the art that the foregoing embodiments are specific examples of carrying out the invention and that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

Claims

1. A method of generating a tooth model with root information, comprising:

acquiring an actual crown model of a single tooth of a patient, and selecting a tooth form parameter model at a position corresponding to the actual crown model;

the tooth form parameter model is obtained by analyzing teeth at the same position in a plurality of historical actual dentition models, and comprises a plurality of form parameters representing tooth shape characteristics;

adjusting morphological parameters in the tooth morphological parameter model to generate a tooth model so that a crown part in the generated tooth model is identical to the shape of the actual crown model;

dividing a tooth root part from the tooth model by taking the edge of the actual tooth crown model as a dividing reference, and taking the tooth root part as a tooth root model to be spliced;

and splicing the tooth root model to be spliced with the actual tooth crown model to obtain a target tooth model with tooth root information.

2. The method of generating a tooth model with root information according to claim 1, wherein determining that a crown portion of the tooth form parameter model is identical to a shape of the actual crown model includes:

Calculating the distance between each vertex on the actual crown model and the corresponding vertex on the tooth form parameter model;

determining whether a crown portion of the tooth form parameter model is identical to the actual crown model in shape according to the calculated distance.

3. The method of generating a tooth model with root information according to claim 2, wherein the determining whether the crown portion of the tooth form parameter model is identical to the actual crown model in shape according to the calculated distance comprises:

determining that the crown portion of the tooth form parameter model is identical to the actual crown model in shape when the calculated average value of the distances between each vertex on the actual crown model and the corresponding vertex on the tooth form parameter model is smaller than a first distance threshold;

or when the sum of the calculated distances between all the vertexes on the actual crown model and the corresponding vertexes on the tooth form parameter model is smaller than a second distance threshold value, determining that the crown part of the tooth form parameter model is identical to the actual crown model in shape;

or determining that the crown portion of the tooth form parameter model is identical to the shape of the actual crown model when the sum of squares of the distances of all the calculated vertices on the actual crown model and the corresponding vertices on the tooth form parameter model is less than a third distance threshold;

Or determining that the crown portion of the tooth form parameter model is identical to the shape of the actual crown model when the calculated maximum distance between each vertex on the actual crown model and the corresponding vertex on the tooth form parameter model is less than a fourth distance threshold.

4. The method of generating a tooth model with root information according to claim 2, wherein the corresponding vertices on the tooth form parameter model are: a vertex on the tooth form parameter model closest to a vertex on the actual crown model;

or is: the apex on the actual crown model projects in its normal direction to form a projected point on the tooth form parameter model.

5. The method for generating a tooth model with root information according to claim 1, wherein the adjusting of the morphological parameters in the tooth morphological parameter model to generate a tooth model so that the crown portion in the generated tooth model is identical to the shape of the actual crown model includes:

and adjusting at least one morphological parameter of the tooth morphological parameter model each time by a preset step length, and judging whether the shape of the crown part of the tooth morphological parameter model is the same as that of the actual crown model after each adjustment until the crown part of the tooth morphological parameter model is determined to be the same as that of the actual crown model.

6. The method according to claim 5, wherein each time one morphological parameter is adjusted, the morphological parameter that affects the shape proximity of the tooth morphological parameter model to the actual crown model the greatest among all the morphological parameters.

7. The method for generating a tooth model with root information according to claim 1, wherein the dividing the root portion from the tooth model with the edge of the actual crown model as a dividing reference includes:

projecting the edge line of the actual crown model in a direction towards the tooth model, and taking a projection curve formed on the tooth model as a dividing line;

the tooth model is separated into a crown portion and a root portion according to the parting line.

8. The method for generating a tooth model with root information according to claim 1, wherein the dividing the root portion from the tooth model with the edge of the actual crown model as a dividing reference includes:

fitting and dividing a curved surface according to the edge line of the actual dental crown model;

The tooth model is separated into a crown portion and a root portion using the segmentation surface.

9. The method for generating a tooth model with root information according to claim 1, wherein the stitching the root model to be stitched with the actual crown model comprises:

orderly stitching the edge line vertexes of the tooth root models to be spliced and the edge line vertexes of the actual tooth crown models to form a triangular network surface patch so as to splice the tooth root models to be spliced and the actual tooth crown models.

10. The method for generating a tooth model with root information according to claim 9, further comprising, after sequentially stitching the edge line vertices of the root model to be spliced with the edge line vertices of the actual crown model to form a triangular network patch:

determining grids within a preset distance from the edge of the stitching part;

and (3) performing fairing treatment on the grid so as to smooth the stitching of the target tooth model.

11. The method for generating a tooth model with root information according to claim 1, wherein in the step of selecting a tooth form parameter model at a position corresponding to the actual crown model, the step of:

Determining a corresponding position according to the tooth number; alternatively, the corresponding position is determined based on the tooth type.

12. The method for generating a tooth model with root information according to claim 1, wherein the tooth morphology parameter model is obtained by analyzing teeth at the same position in a plurality of historic actual dentition models, comprising:

respectively deforming the tooth standard model at the same position as the tooth morphological parameter model until the tooth standard model is the same as the shape of each historical actual dentition model, so as to obtain a plurality of deformed tooth standard models;

and analyzing the plurality of deformed tooth standard models to obtain the tooth morphological parameter model.

13. The method for generating a tooth model with root information according to claim 12, further comprising, before the deforming the tooth standard model at the same position as the tooth morphological parameter model, respectively:

aligning the tooth standard model with the teeth at the same position in the historical actual dentition model;

wherein the alignment method comprises the following steps: alignment according to a coordinate system and/or feature point alignment.

14. The method of generating a tooth model with root information according to claim 13, wherein the coordinate system alignment includes alignment according to coordinate system information including:

Taking any position of the center of gravity of the single tooth, the midpoint of the gum line of the single tooth, the impedance center point of the single tooth moving and the cusp of the root of the single tooth as the origin of a coordinate system;

and determining an X-axis direction according to the Y-axis direction and the Z-axis direction by taking the direction of the tooth axis as a Z-axis direction and taking the connecting line direction of the labial side and the lingual side as a Y-axis direction, wherein the X-axis direction is perpendicular to the Y-axis direction and the Z-axis direction respectively.

15. The method for generating a tooth model with root information according to claim 13, wherein the feature point alignment comprises: aligning according to the characteristic point information;

if the tooth type of the tooth standard model is incisors or cuspids, the feature point information includes: mesial and distal to the incisal margin of the tooth;

if the tooth type of the tooth standard model is premolars, the characteristic point information comprises: lingual bumps and labial bumps;

if the tooth type of the tooth standard model is post-molar, the feature point information includes: a bump in the lingual proximal direction, a bump in the labial proximal direction, a bump in the lingual distal direction, and a bump in the labial distal direction.

16. The method of generating a tooth model with root information according to any one of claims 1-15, wherein the tooth morphology parameter model is obtained by analyzing teeth at the same location in a plurality of historical actual dentition models, comprising:

Analyzing teeth at the same position in a plurality of historical actual dentition models by adopting a principal component analysis method to obtain a position average value of vertexes of the same serial number in each model and a characteristic vector for representing tooth morphology;

and calculating according to the position average value and the characteristic vector to obtain a tooth morphology parameter model.

17. The method of generating a tooth model with root information according to claim 16, wherein before analyzing teeth at the same location in the plurality of historical actual dentition models using principal component analysis, the method comprises:

and unifying the resolutions and vertex serial numbers of the plurality of historical actual dentition models.

18. The method for generating a tooth model with root information according to claim 12, wherein the analyzing the plurality of deformed tooth standard models to obtain the tooth morphological parameter model includes:

analyzing the vertexes of the deformed tooth standard models by adopting a principal component analysis method to obtain the position average value of the vertexes of the same serial number and the characteristic vector for representing the tooth morphology;

19. The method for generating a tooth model with root information according to claim 1, wherein the acquiring an actual crown model of a single tooth of a patient comprises:

obtaining an actual dentition model of the patient by oral scanning;

and dividing the actual dentition model to obtain an actual crown model of the single tooth.

20. A method of generating a dentition model with root information, comprising:

the method for generating a tooth model according to any one of claims 1 to 19, wherein the tooth model with root information is generated corresponding to all individual teeth of the patient;

and arranging the tooth models according to the tooth positions to obtain a dentition model with tooth root information.

21. The method for generating a dental model with root information according to claim 20, further comprising, after the arranging of each dental model according to the tooth positions:

judging whether two tooth roots collide with each other in the tooth column model with tooth root information;

if present, the root portions of the two tooth models that collide with each other are deformed to eliminate the collision.

22. The method according to claim 21, wherein the determining whether there are two tooth models in which roots collide with each other in the tooth model with root information comprises:

Obtaining a detection plane between two adjacent tooth models, wherein the detection plane is as follows: taking the direction of the connecting line of the centers of gravity of the two adjacent tooth models as the normal direction of the detection plane, and establishing a plane passing through the midpoint of the connecting line of the centers of gravity;

if neither of the two adjacent tooth models passes through the detection plane, the two adjacent tooth models do not collide with each other;

if at least one of the two adjacent tooth models passes through the detection plane, the two adjacent tooth models collide with each other.

23. The method of generating a dentition model with root information according to claim 21, wherein deforming root portions of two tooth models that collide with each other to eliminate the collision comprises:

acquiring a reference plane between two mutually collided tooth models, wherein the reference plane is a plane established by taking the direction of the connecting line of the centers of gravity of the two adjacent tooth models as the normal direction of the reference plane and passing through the midpoint of the connecting line of the centers of gravity;

determining a maximum intersection depth between a root portion of a tooth model passing through the reference plane and the reference plane, and a root apex corresponding to the maximum intersection depth;

Determining a projection point of the root apex on the reference plane in the direction of the intersecting depth as a moving target point;

and in the condition that the crown part of the tooth model passing through the reference plane does not move, performing deformation operation on the root part of the tooth model passing through the reference plane so as to move the position of the root apex to the movement target point and eliminate the collision.

24. A method of establishing a dental appliance, comprising:

obtaining a dental model of a patient according to the method of generating a dental model with root information of any one of claims 20 to 23;

designing a target correction position of each tooth according to the crown characteristic information and the root characteristic information of each tooth in the dentition model;

a dental appliance plan for the patient is determined based on the target appliance locations for all teeth.

25. An electronic device, comprising:

at least one processor; the method comprises the steps of,

a memory communicatively coupled to the at least one processor; wherein,

the memory stores instructions executable by the at least one processor to enable the at least one processor to perform the method of generating a dental model with root information as claimed in any one of claims 1 to 19, or to enable the at least one processor to perform the method of generating a dental model with root information as claimed in any one of claims 20 to 23, or to enable the at least one processor to perform the method of formulating a dental appliance as claimed in claim 24.

26. A computer-readable storage medium storing a computer program, wherein the computer program when executed by a processor realizes the method for generating a dental model with root information according to any one of claims 1 to 19, or the computer program when executed by a processor realizes the method for generating a dental model with root information according to any one of claims 20 to 23, or the computer program when executed by a processor realizes the method for preparing a dental correction scheme according to claim 24.