Construction method of orthodontic treatment effect evaluation system

Abstract

The invention discloses a construction method of an orthodontic treatment effect evaluation system, and relates to the technical field of orthodontic evaluation. Comprising the following steps: importing standard tooth model data and an orthodontic scheme, scanning the interior of an oral cavity to obtain tooth data, obtaining a mouth beauty line, constructing an actual oral cavity model of a patient based on the tooth data, inputting the orthodontic scheme into the oral cavity model to generate a post-orthodontic model, and comparing the post-orthodontic model with a standard tooth model to obtain a tooth error value. Simulating a mouth image based on the post-orthodontic model, obtaining a post-orthodontic mouth line based on feature points of the mouth image, comparing the post-orthodontic mouth line with the mouth beauty line to obtain a mouth error value, and constructing an evaluation system based on the tooth error value and the mouth error value to evaluate the orthodontic curative effect. According to the method, the effect of the patient before and after treatment can be objectively and comprehensively evaluated, and a scientific decision basis is provided for orthodontic doctors.

Description

Technical Field

[0001] The present invention relates to the technical field of orthodontic evaluation, and particularly to a construction method of an orthodontic treatment effect evaluation system. Background Art

[0002] The abundance of social material life has enabled the pace of human spiritual pursuit to move forward all the way. For doctors and patients in the field of orthodontics, well-aligned tooth rows and occlusions that meet chewing functions are no longer the only pursuits of orthodontics. The improvement of facial aesthetics brought about by orthodontic treatment is even more desired by people. Solving dental alignment and occlusion health problems through orthodontic treatment while improving facial aesthetics is the result that orthodontic doctors and patients both hope to achieve. However, at present, traditional follow-up examinations and evaluations mainly rely on the naked-eye observation and experience of orthodontic doctors to make judgments, and are supplemented by radiological examination means when necessary, but the treatment effects cannot be accurately evaluated, which has a certain impact on the final treatment effect.

[0003] Therefore, how to provide a construction method of an orthodontic treatment effect evaluation system to solve the difficulties existing in the prior art is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0004] In view of this, the present invention provides a construction method of an orthodontic treatment effect evaluation system, which can objectively and comprehensively evaluate the effects before and after the treatment of patients, and provide a scientific decision-making basis for orthodontic doctors.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A construction method of an orthodontic treatment effect evaluation system includes the following steps:

[0007] S1. Import standard tooth model data and orthodontic treatment plans, scan the interior of the oral cavity to obtain tooth data, and obtain the aesthetic line of the mouth;

[0008] S2. Construct an actual oral cavity model of the patient based on the tooth data, and input the orthodontic treatment plan into the oral cavity model to generate a post-orthodontic model;

[0009] S3. Compare the post-orthodontic model with the standard tooth model to obtain a tooth error value;

[0010] S4. Simulate a mouth image based on the post-orthodontic model, and obtain a post-orthodontic mouth line based on the feature points of the mouth image;

[0011] S5. Compare the post-orthodontic mouth line with the aesthetic line of the mouth to obtain a mouth error value;

[0012] S6. Construct an evaluation system based on the tooth error value and the mouth error value to evaluate the orthodontic treatment effect.

[0013] Optionally, in S1, the aesthetic line of the mouth includes the nasolabial fold, the lips, and the middle line of the lower 1 / 3 of the face.

[0014] Optionally, in S3, the model comparison includes:

[0015] S31. Obtain the center points of the teeth in the post-orthodontic model and the center points of the teeth in the standard tooth model;

[0016] S32. Construct a plane rectangular coordinate system and place the center points of the teeth in the plane rectangular coordinate system;

[0017] S33. Find the center points of the teeth at the turning parts;

[0018] S34. Compare the center points of the teeth in the post-orthodontic model with the center points of the teeth in the standard tooth model at the turning parts to obtain the turning offset;

[0019] S35. Determine the tooth error value based on the turning offset.

[0020] Optionally, constructing the plane rectangular coordinate system in S32 includes: Connect the center points of two incisors to form a line segment, extend both ends of the line segment as the X-axis, draw a perpendicular line through the midpoint of the line segment, use the perpendicular line as the Y-axis, and use the midpoint as the coordinate origin.

[0021] Optionally, the expression for the turning offset in S34 is:

[0022] where d i represents the turning offset of the i-th tooth in the post-orthodontic model, and X ai , Y ai respectively represent the horizontal and vertical coordinates of the center point of the i-th tooth in the post-orthodontic model, and X bi , Y bi respectively represent the horizontal and vertical coordinates of the center point of the i-th tooth in the standard tooth model.

[0023] Optionally, in S4, simulating the mouth image includes: Obtain the initial facial image by acquiring the distribution of facial soft tissues, and simulate the change of facial soft tissues of the patient after orthodontics based on the tooth positions in the post-orthodontic model to obtain the facial image after orthodontics.

[0024] Optionally, the method for obtaining the mouth error value in S5 includes:

[0025] S51. Obtain the 3D facial image;

[0026] S52. Use the nasal base as the coordinate origin to construct a three-dimensional coordinate axis. Use the line parallel to the connection line of the left and right tragus points as the x-axis, use the point perpendicular to the connection line of the left and right tragus points horizontally as the z-axis, and draw a straight line perpendicular to the x-axis and the z-axis as the y-axis;

[0027] S53. Randomly select three points on the nasolabial groove, lips and the middle line of the lower 1 / 3 of the face to generate three-dimensional coordinates, and adjust the coordinate positions based on the post-orthodontic model to form post-orthodontic coordinates.

[0028] S54. Input the aesthetic line of the mouth into the three-dimensional coordinate axis to obtain the standard point coordinates corresponding to the post-orthodontic coordinate points.

[0029] S55. Compare the post-orthodontic coordinates with the standard point coordinates to form the mouth error value.

[0030] As can be seen from the above technical solutions, compared with the prior art, the present invention provides a method for constructing an orthodontic treatment effect evaluation system, which has the following beneficial effects: The present invention comprehensively evaluates the impact of orthodontic treatment on facial aesthetics based on the nasolabial groove, lips and the middle line of the lower 1 / 3 of the face, provides relevant aesthetic reference basis in the process of formulating orthodontic treatment and preoperative communication with patients, can objectively and comprehensively evaluate the treatment effects before and after treatment for patients, and provides a scientific decision-making basis for orthodontic doctors. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0032] Figure 1 It is a flowchart of a method for constructing an orthodontic treatment effect evaluation system disclosed by the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0034] Refer to Figure 1 As shown, the present invention discloses a method for constructing an orthodontic treatment effect evaluation system, including the following steps:

[0035] S1. Import standard tooth model data and orthodontic treatment plan, scan the internal cavity of the mouth to obtain tooth data, and obtain the aesthetic line of the mouth.

[0036] S2. Based on the tooth data, construct the actual oral cavity model of the patient, and input the orthodontic treatment plan into the oral cavity model to generate a post-orthodontic model.

[0037] S3. Compare the orthodontic model with the standard tooth model to obtain the tooth error value;

[0038] S4. Simulate the mouth image based on the orthodontic model and obtain the orthodontic mouth line based on the feature points of the mouth image;

[0039] S5. Compare the orthodontic mouth line with the aesthetic mouth line to obtain the mouth error value;

[0040] S6. Construct an evaluation system based on the tooth error value and the mouth error value to evaluate the orthodontic efficacy.

[0041] Further, the aesthetic mouth line in S1 includes the nasolabial groove, the lip, and the middle line of the lower 1 / 3 face.

[0042] Further, the model comparison in S3 includes:

[0043] S31. Obtain the center points of the teeth in the orthodontic model and the center points of the teeth in the standard tooth model;

[0044] S32. Construct a rectangular coordinate system and place the center points of the teeth in the rectangular coordinate system;

[0045] S33. Find the center points of the teeth at the turning parts;

[0046] S34. Compare the center points of the teeth in the orthodontic model and the center points of the teeth in the standard tooth model at the turning parts to obtain the turning offset;

[0047] S35. Determine the tooth error value based on the turning offset.

[0048] Further, the center point of the tooth is selected as the midpoint of the tooth part exposed with the gum.

[0049] Further, the construction of the rectangular coordinate system in S32 includes: Connect the center points of the two front teeth to form a line segment, extend both ends of the line segment as the X-axis, draw a perpendicular line through the midpoint of the line segment, and the perpendicular line is used as the Y-axis, and the midpoint is used as the coordinate origin.

[0050] Further, the determination of the turning parts in S33 includes:

[0051] Obtain the coordinates of all the center points of the orthodontic teeth and the coordinates of the center points of the standard teeth based on the rectangular coordinate system to obtain the orthodontic data set and the standard data set;

[0052] Obtain the orthodontic coordinates and the standard coordinates of the corresponding paired teeth, and compare the standard errors of the coordinates. Specifically, obtain the distance between the paired teeth, compare the distance after orthodontics with the distance of the standard teeth, and the expression can be written as: Δ = |L a -L b |, where L a represents the distance between the paired teeth in the orthodontic model, Lb It represents the distance between a pair of teeth in the standardized post-treatment model.

[0053] Set Δ max , and judge the magnitude of the calculated Δ and Δ max . If Δ ≥ Δ max , directly end the evaluation, judge that the orthodontic effect this time is unacceptable, and revise the orthodontic plan; otherwise, continue to the next step.

[0054] Obtain three adjacent center points, connect two adjacent points among them, and judge whether the generated line is a broken line or a straight line. When it is judged that a broken line is generated, use the middle point of the three midpoints as the turning part.

[0055] Furthermore, the turning offset expression in S34 is:

[0056] where d i represents the turning offset of the i-th tooth in the post-orthodontic model, and X ai , Y ai respectively represent the horizontal and vertical coordinates of the center point of the i-th tooth in the post-orthodontic model, and X bi , Y bi respectively represent the horizontal and vertical coordinates of the center point of the i-th tooth in the standard tooth model.

[0057] Specifically, the turning offset is used to judge whether the distance of the turning part is within the turning range.

[0058] Furthermore, the simulated mouth image in S4 includes: obtaining the initial facial image by acquiring the facial soft tissue distribution, and simulating the change of the facial soft tissue of the patient after orthodontics based on the tooth positions in the post-orthodontic model to obtain the facial image after orthodontics.

[0059] Furthermore, the method for obtaining the mouth error value in S5 includes:

[0060] S51. Obtain a 3D facial image;

[0061] S52. Use the nasolabial fold as the coordinate origin to construct a three-dimensional coordinate axis. Use the line parallel to the connection line of the left and right tragus points as the x-axis, use the point perpendicular to the connection line of the left and right tragus points horizontally as the z-axis, and make a straight line perpendicular to the x-axis and z-axis as the y-axis;

[0062] S53. Randomly select three points on the nasolabial groove, lip, and lower 1 / 3 facial midline of the face to generate three-dimensional coordinates, and adjust the coordinate positions based on the post-orthodontic model to form post-orthodontic coordinates;

[0063] S54. Input the mouth aesthetic line into the three-dimensional coordinate axis to obtain the standard point coordinates corresponding to the post-orthodontic coordinate points;

[0064] S55. Compare the coordinates after orthodontics with the coordinates of the standard points to form the mouth error value.

[0065] Specifically, obtaining facial 3D images includes: using the 3dMD face stereoscopic tomography system to collect 3dMD data of the patient's face. The image error obtained by 3dMD face is less than 0.2mm, which can accurately collect the patient's facial features. During use, the patient needs to sit in the middle of the instrument with a natural head position, relax facial muscles, naturally bite the upper and lower teeth, and have no micro-expressions. Adjust the lighting and chair position so that the patient's head is in the best position on the screen and remains motionless; at the same time, debug and align the 3dMD face stereoscopic tomography system. When the photography system is ready, immediately click the camera button to complete the 1.5 millisecond shooting. After the shooting is completed, a three-dimensional image of the patient's face will be formed in the 3dMD built-in software.

[0066] It also includes preprocessing of three-dimensional images: trimming the edges of the three-dimensional image with a fixed coordinate system, removing hair, neck, and clothing, and retaining relevant facial soft tissue.

[0067] Further, the adjustment based on the post-orthodontic model includes determining whether the orthodontic site is anterior teeth or posterior teeth.

[0068] Specifically, when the orthodontic site is the anterior teeth, the muscle activity of the lip closing movement is mainly participated by the mentalis muscle. The tension of the mentalis muscle is directly related to the chin morphology when the lips are closed, and the spatial position of the anterior teeth is an important factor affecting the tension of the mentalis muscle. After orthodontics, accompanied by the posterior movement of the anterior teeth, the chin morphology tends to be better. Specifically, the soft tissue thickness at the anterior chin point increases significantly, and the soft tissue thickness at the lower alveolar seat point decreases significantly. The change in soft tissue thickness at the lower alveolar seat point is negatively correlated with the posterior movement of the lower incisor, with a correlation coefficient of -0.376.

[0069] When the orthodontic site is the posterior teeth, it is divided into the effects of distal movement and elongation on soft tissue morphology, and the effects of mesial movement and depression on soft tissue morphology;

[0070] When the posterior teeth move distally and extend, the change in the mandibular plane angle is significantly negatively correlated with the sagittal change of the lower lip, while the sagittal change of the upper lip is not obvious. When the molars move distally, the fulcrum moves distally and the mandible rotates clockwise, causing the soft tissue chin point to move posteriorly. During the bite opening process, the degree of vertical upward extrusion of the upper and lower lips becomes smaller to compensate for the change in vertical distance. Therefore, the soft tissue coordinates of the lip move based on the sagittal and y-axis directions of the teeth.

[0071] When the posterior teeth are moved mesially and intruded, the intermaxillary distance is slightly reduced, which relaxes the originally tense mentalis and orbicularis oris muscles, so the soft tissue coordinates of the lips move based on the x-axis.

[0072] Further, the three-dimensional coordinates input for the aesthetic line of the mouth in S44 include: translating the centroid coordinates to the origin of the established coordinate system, scaling them to the unit centroid size, and rotating each face configuration to minimize the square root of the sum of the squared Euclidean distances between the corresponding landmarks of each configuration, where the centroid is the geometric center of the object calculated from the arithmetic mean of all landmark coordinates.

[0073] Further, the expression for determining the mouth error value is:

[0074]

[0075] where x zi 、y zi and z zi respectively represent the x-axis, y-axis, and z-axis coordinates of the i-th point selected for the mouth of the orthodontic model, and x mi 、y mi and z mi respectively represent the x-axis, y-axis, and z-axis coordinates of the i-th point selected for the aesthetic line of the mouth.

[0076] Further, in S6, the construction of an evaluation system to evaluate the orthodontic efficacy is to use the entropy weight method for evaluation. Set multiple variables including the tooth error value and the mouth error value, determine the corresponding evaluation indicators, construct a positive matrix from the variables and evaluation indicators, standardize the matrix, and judge whether there are negative numbers in the matrix. If so, another standardization method needs to be used to standardize the positive matrix once to obtain a standardized matrix, calculate the probability matrix and each element in the probability matrix to ensure that the sum of each column of the probability matrix is 1, obtain the information utility value and normalize it, obtain the evaluation index, and determine the orthodontic situation based on the evaluation index and judge whether to continue or revise the treatment course.

[0077] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but rather to the broadest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for constructing an orthodontic treatment effect evaluation system, characterized in that, It includes the following steps: S1. Import standard tooth model data and orthodontic treatment plans, scan the interior of the oral cavity to obtain tooth data, and obtain the aesthetic line of the mouth; S2. Based on the tooth data, construct the actual oral cavity model of the patient, and input the orthodontic treatment plan into the oral cavity model to generate the post-orthodontic model; S3. Compare the post-orthodontic model with the standard tooth model to obtain the tooth error value; S4. Simulate the mouth image based on the post-orthodontic model, and obtain the post-orthodontic mouth line based on the feature points of the mouth image; S5. Compare the post-orthodontic mouth line with the aesthetic line of the mouth to obtain the mouth error value; S6. Based on the tooth error value and the mouth error value, construct an evaluation system to evaluate the orthodontic treatment effect.

2. The construction method of an orthodontic treatment effect evaluation system according to claim 1, wherein the aesthetic line of the mouth in S1 includes the nasolabial groove, the lips, and the middle line of the lower 1 / 3 face.

3. The construction method of an orthodontic treatment effect evaluation system according to claim 1, wherein the model comparison in S3 includes: S31. Obtain the center points of the teeth in the post-orthodontic model and the center points of the teeth in the standard tooth model; S32. Construct a rectangular coordinate system, and place the center points of the teeth in the rectangular coordinate system; S33. Find the center points of the teeth at the turning parts; S34. Compare the center points of the teeth in the post-orthodontic model with the center points of the teeth in the standard tooth model at the turning parts to obtain the turning offset; S35. Determine the tooth error value based on the turning offset.

4. The construction method of an orthodontic treatment effect evaluation system according to claim 3, wherein constructing the rectangular coordinate system in S32 includes: connecting the center points of two central incisors to form a line segment, extending both ends of the line segment as the X-axis, drawing a perpendicular line through the midpoint of the line segment, using the perpendicular line as the Y-axis, and using the midpoint as the coordinate origin.

5. The construction method of an orthodontic treatment effect evaluation system according to claim 3, wherein The turning offset expression in S34 is as follows: Among them, d i represents the turning offset of the i-th tooth in the orthodontic model, X ai , Y ai respectively represent the horizontal and vertical coordinates of the center point of the i-th tooth in the orthodontic model, X bi , Y bi respectively represent the horizontal and vertical coordinates of the center point of the i-th tooth in the standard tooth model.

6. The construction method of an orthodontic treatment effect evaluation system according to claim 2, wherein simulating the mouth image in S4 includes: obtaining the distribution of facial soft tissues to obtain the initial facial image, and simulating the changes in facial soft tissues of the post-orthodontic patient based on the tooth positions in the post-orthodontic model to obtain the post-orthodontic facial image.

7. The construction method of an orthodontic treatment effect evaluation system according to claim 6, wherein the method for obtaining the mouth error value in S5 includes: S51. Obtain the 3D facial image; S52. Take the nasal base as the coordinate origin, construct three-dimensional coordinate axes, use the line parallel to the connection line of the left and right tragus points as the x-axis, use the point perpendicular to the connection line of the left and right tragus points horizontally as the z-axis, and draw a straight line perpendicular to the x-axis and the z-axis as the y-axis; S53. Randomly select 3 points on the nasolabial groove, the lips, and the middle line of the lower 1 / 3 face of the face to generate three-dimensional coordinates, and adjust the coordinate positions based on the post-orthodontic model to form the post-orthodontic coordinates; S54. Input the aesthetic line of the mouth into the three-dimensional coordinate axes to obtain the standard point coordinates corresponding to the post-orthodontic coordinate points; S55. Compare the post-orthodontic coordinates with the standard point coordinates to form the mouth error value.

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