Method, program, storage medium, and apparatus for uniformizing tooth contact value based on dental arch wire

Abstract

The invention relates to an optimization method based on a uniform tooth contact value of a dental arch line. The optimization method is used for improving a tooth occlusion relation and contact force distribution. According to the method, a dental arch line is taken as a reference, and a homogenized model of a tooth contact value is constructed by combining mechanical analysis through a digital modeling technology. The method specifically comprises the following steps: firstly, performing three-dimensional scanning on a single-jaw tooth to obtain a tooth geometric shape; secondly, establishing a dental arch curve by using a mathematical fitting method, and performing movement distribution design of tooth contact points by taking the dental arch curve as a reference; and finally, obtaining a uniform tooth arrangement position through iterative calculation. According to the method, uniform distribution of single-jaw tooth contact values can be realized, the problem of local overload caused by uneven contact force in dentition is reduced, so that the damage risk of teeth and periodontium is reduced, the method can be used as a design reference in the orthodontic and repair process, the suitability and functionality of an orthodontic appliance or a repair body are improved, and the application prospect is wide. A new technical thought is provided for orthodontic and repair, and the method has important clinical popularization and application value.

Description

Technical Field

[0001] The present invention relates to the technical field of orthodontics, and particularly to a method, program, storage medium and device for uniform tooth contact values based on an arch wire. Background Art

[0002] Orthodontics is a discipline that studies tooth arrangement, occlusion relationships, and the prevention and treatment of maxillofacial development and deformities. During orthodontic treatment, it is crucial to ensure uniform tooth contact on the arch wire, which helps to achieve good occlusion function and aesthetic effects.

[0003] The evaluation of artificial uniform tooth contact values often relies on the subjective judgment and experience of orthodontists or dental technicians. Different doctors or technicians may have different views and evaluation results on the tooth contact situation of the same patient, which may lead to differences and uncertainties in treatment plans. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to design a method, program, storage medium and device for uniform tooth contact values based on an arch wire, which is used to improve the accuracy and effect of orthodontic treatment and solve the existing technical problems.

[0005] To solve the above technical problems, the present invention proposes a method for uniform tooth contact values based on an arch wire, including the following steps:

[0006] Step S1: Obtain basic tooth information, where the basic information includes single-jaw teeth and their arch wire.

[0007] Step S2: Calculate the contact values between adjacent teeth in the dental arch respectively, and calculate the average value of all tooth contact values.

[0008] Step S3: Fix the head and tail teeth, traverse the dental arch, start moving from the teeth on both sides of the dental arch at the same time, calculate the moving direction of the current tooth on the arch wire, and the target moving amount is the difference x between the initial state of the current tooth, x = the average value of all tooth contact values - the contact value between the current tooth and the adjacent tooth, and use the function Calculate the current moving amount to approach the target moving amount, x is the difference, F(x) is the current moving amount, and b is a constant that changes with the range of x. The calculation method of b is:

[0009] Step (1): Set the initial value b of b 0 , and obtain the current difference x;

[0010] Step (2): Repeat the following steps until the exit condition is met:

[0011] Judge the size of x and b. If x < b, then set b = kb, where

[0012] If x≥b, exit the loop and return the current value of b.

[0013] Step S4: recalculate the contact value of the moved teeth, and recalculate the average value of all tooth contact values. If the tooth contact value and the average value are within the medical error range, the process ends; otherwise, the process returns to step S3.

[0014] Furthermore, in step S1, the dental arch wire is obtained by:

[0015] (1) obtaining characteristic points describing the dental arch morphology, wherein the characteristic points include the molar cusp, canine cusp, and central incisor midpoint;

[0016] (2) Substitute the feature points into the univariate quartic polynomial function ax 4 +bx 2 In +c, the least square method is used to adjust the function parameters a, b, and c so that the function curve is as close as possible to the shape of the actual dental arch curve, and the final calculated function is used as the dental arch line.

[0017] Furthermore, in step S2, OBBTree is used to perform intersection detection on two adjacent teeth. If the two teeth intersect, the collision value is taken as the contact value. If they do not intersect, the gap value is taken as the contact value. When calculating the average value of all tooth contact values, the collision value is a positive number and the gap value is a negative number.

[0018] Furthermore, the collision value is calculated as follows: fit the point set In where the two teeth intersect into a plane Plane, and calculate the mean midpoint Center of the point set In, project it onto the two teeth with Center as the endpoint and the normal vector of the plane Plane as the direction, and take the sum of the distances between the two points closest to Center after being projected to the teeth and the midpoint Center as the collision value.

[0019] Furthermore, the gap value is calculated by constructing a KDTree using the vertices of the two tooth meshes respectively, and calculating the distance between the closest points of the two nearest KDTrees as the gap value.

[0020] Furthermore, in step S3, the initial value b 0 The value range of is:

[0021] Further, in step S3,

[0022] The present invention also provides a computer program product, comprising computer instructions, which, when executed by a processor, enable a computer device to perform the aforementioned method of uniform tooth contact value based on dental arch line.

[0023] The present invention also provides a computer-readable storage medium having computer-executable instructions stored thereon. When a processor executes the computer-executable instructions, the method of uniform tooth contact value based on dental arch line as described above is implemented.

[0024] The present invention also provides a device for uniform tooth contact value based on dental arch line, comprising:

[0025] at least one processor; and

[0026] at least one memory in communication with the processor;

[0027] The memory stores instructions that can be executed by the processor, and the instructions are executed by the processor to enable the device to perform the aforementioned method based on uniform tooth contact values ​​of dental arch lines.

[0028] Beneficial effects of the present invention:

[0029] 1. Improve contact uniformity. The method of uniform tooth contact value of the present invention can achieve uniform distribution of single-jaw tooth contact value, reduce local overload problems caused by uneven contact force in the dentition, and thus reduce the risk of damage to teeth and periodontal tissues.

[0030] 2. Reduce tooth wear. Uniform contact force distribution can reduce abnormal wear of teeth caused by local excessive force and extend the service life of teeth.

[0031] 3. Optimize correction and restoration effects. In the process of tooth correction and restoration, the method of uniform tooth contact value of the present invention can be used as a design reference to improve the adaptability and functionality of the appliance or restoration and enhance the treatment effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The specific implementation of the present invention will be further explained below in conjunction with the accompanying drawings.

[0033] Figure 1 A flow chart of the method for uniform tooth contact value based on dental arch line in the present invention;

[0034] Figure 2 is a schematic diagram of a dental arch wire in the present invention;

[0035] Figure 3 It is a schematic diagram of a plane fitting of the intersection point set of two intersecting teeth in the present invention;

[0036] Figure 4 A schematic diagram of the connection lines of the collision projection points in the present invention;

[0037] Figure 5 A schematic diagram of a line connecting the closest points of a gap in the present invention;

[0038] Figure 6It is a schematic diagram of the contact values ​​of each tooth before uniformity in the present invention;

[0039] Figure 7 It is a schematic diagram of each tooth after uniform contact in the present invention. DETAILED DESCRIPTION

[0040] Example 1

[0041] Combination Figure 1 This embodiment provides a method for uniform tooth contact value based on dental arch line, which specifically includes the following steps:

[0042] Step S1: Obtain basic tooth information, which includes single-jaw teeth and their dental arch lines.

[0043] In this embodiment, preferably, in step S1, the dental arch wire is obtained by:

[0044] (1) obtaining characteristic points describing the dental arch morphology, wherein the characteristic points include the molar cusp, canine cusp, and central incisor midpoint;

[0045] (2) Substitute the feature points into the univariate quartic polynomial function ax 4 +bx 2 +c, the least square method is used to adjust the function parameters a, b, c, so that the function curve is as close as possible to the shape of the actual dental arch curve, and the final calculated function is used as the dental arch line, such as Figure 2 As shown, the green curve is the dental arch line.

[0046] Step S2: Calculate the contact values ​​between adjacent teeth in the dentition respectively, and calculate the average value of all tooth contact values.

[0047] Preferably, in step S2 of the present embodiment, OBBTree is used to perform intersection detection on two adjacent teeth. If the two teeth intersect, the collision value is taken as the contact value. If they do not intersect, the gap value is taken as the contact value. When calculating the average value of all tooth contact values, the collision value is a positive number and the gap value is a negative number.

[0048] In this embodiment, the collision value is preferably calculated by fitting the point set In where the two teeth intersect into a plane Plane, such as Figure 3 As shown, the mean midpoint Center of the In point set is calculated, and Center is used as the endpoint and the normal vector of the plane Plane is used as the direction to project onto the two teeth. The sum of the distances between the two points closest to Center after projection onto the teeth and the midpoint Center is taken as the collision value, as shown in Figure 4 As shown, the sum of the lengths of the blue line segment and the red line segment in the figure is the collision value.

[0049] Preferably, in this embodiment, the calculation method of the clearance value is as follows: KD-Trees are respectively constructed with the vertices of the two tooth meshes, and the distance between the two closest points of the two KD-Trees is calculated as the clearance value. As Figure 5 shown, the length of the red line segment in the figure is the clearance value.

[0050] Step S3: Fix the first and last teeth, traverse the dental arch, start moving from the teeth on both sides of the dental arch simultaneously, calculate the moving direction of the current tooth on the dental arch line, and the target moving amount is the difference x between the current state of the tooth, where x = the average value of all tooth contact values - the contact value between the current tooth and the adjacent tooth. Use the function to calculate the current moving amount approaching the target moving amount, where x is the difference, F(x) is the current moving amount, and b is a constant that changes with the range of x. The calculation method of b is as follows:

[0051] Step (1): Set the initial value b 0 of b. The setting of b 0 needs to consider whether there is tooth extraction in the current dental arch. For the case of tooth extraction, the initial value b 0 should be set larger appropriately to obtain the current difference x;

[0052] Step (2): Repeat the following steps until the exit condition is met:

[0053] Judge the magnitudes of x and b. If x < b, then set b = kb, where the larger the value of k, the higher the accuracy, but the slower the speed. Specifically, in this embodiment, take That is, during iteration, when x < b, the value of b is updated to

[0054] If x ≥ b, then exit the loop and return the current value of b.

[0055] Preferably, in this embodiment, in step S3, the initial value b 0 has a value range of:

[0056]

[0057] Step S4: Recalculate the contact value of the moved teeth and recalculate the average value of all tooth contact values. If the tooth contact value and the average value are within the medical error range, then end; otherwise, continue to return to step S3.

[0058] Specifically, in this embodiment, the error range between the tooth contact value and the average value is selected to be less than 0.01 mm.

[0059] In this embodiment, taking the case of no tooth extraction and tooth loss as an example, the initial value b 0=0.1mm, the effect before and after moving is as follows Figure 6 and Figure 7 As shown, Figure 6 The contact values ​​(gap) of the middle teeth and jaws are basically concentrated in one area (left side of the picture). After using the method of uniform tooth contact values ​​in this embodiment, the contact values ​​are evenly distributed to each tooth. The effect is as follows: Figure 7 shown.

[0060] Example 2

[0061] This embodiment provides a computer program product, including computer instructions, which, when executed by a processor, enable a computer device to execute the method of uniform tooth contact values ​​based on dental arch lines as in Embodiment 1.

[0062] Example 3

[0063] This embodiment provides a computer-readable storage medium having computer-executable instructions stored thereon. When a processor executes the computer-executable instructions, the method based on uniform tooth contact values ​​of dental arch lines as in Embodiment 1 is implemented.

[0064] Example 4

[0065] This embodiment provides a device for uniform tooth contact value based on dental arch line, comprising:

[0066] at least one processor; and

[0067] at least one memory in communication with the processor;

[0068] The memory stores instructions that can be executed by the processor, and the instructions are executed by the processor to enable the device to perform the method of uniform tooth contact value based on dental arch line in Example 1.

[0069] Many specific details are described in the above description to facilitate a full understanding of the present invention. However, the above description is only a preferred embodiment of the present invention. The present invention can be implemented in many other ways different from those described herein, so the present invention is not limited to the specific implementation disclosed above. At the same time, any person familiar with the art can make many possible changes and modifications to the technical solution of the present invention using the methods and technical contents disclosed above without departing from the scope of the technical solution of the present invention, or modify it into an equivalent embodiment of equivalent changes. Any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the scope of protection of the technical solution of the present invention.

Claims

1. A method based on uniform tooth contact value of dental arch line, characterized by: The steps include: Step S1: Obtaining basic tooth information, the basic information including single-jaw teeth and their dental arch lines; Step S2: Calculate the contact values ​​between adjacent teeth in the dentition respectively, and calculate the average value of all tooth contact values; Step S3: Fix the first and last teeth, traverse the dentition, start from the teeth on both sides of the dentition and move simultaneously, calculate the movement direction of the current tooth on the dental arch line, and the target movement amount is the difference x of the initial state of the current tooth, x = the average value of all tooth contact values ​​- the contact value between the current tooth and the adjacent teeth, and use the function Calculate the current movement amount approaching the target movement amount, x is the difference, F(x) is the current movement amount, b is a constant that changes with the range of x, and the calculation method of b is: Step (1): Set the initial value b0 of b and obtain the current difference x; Step (2): Repeat the following steps until the exit condition is met: Determine the magnitude relationship between x and b. If x < b, then set b = kb, where, If x≥b, exit the loop and return the current value of b; Step S4: recalculate the contact value of the moved teeth, and recalculate the average value of all tooth contact values. If the tooth contact value and the average value are within the medical error range, the process ends; otherwise, the process returns to step S3.

2. The method according to claim 1, characterized in that: In step S1, the dental arch wire is obtained by: (1) obtaining characteristic points describing the dental arch morphology, wherein the characteristic points include the molar cusp, canine cusp, and central incisor midpoint; (2) Substitute the feature points into the univariate quartic polynomial function ax 4 +bx 2 In +c, the least square method is used to adjust the function parameters a, b, and c so that the function curve is as close as possible to the shape of the actual dental arch curve, and the final calculated function is used as the dental arch line.

3. The method according to claim 1, characterized in that: In step S2, OBBTree is used to perform intersection detection on two adjacent teeth. If the two teeth intersect, the collision value is taken as the contact value. If they do not intersect, the gap value is taken as the contact value. When calculating the average value of all tooth contact values, the collision value is a positive number and the gap value is a negative number.

4. The method according to claim 3, characterized in that: The collision value is calculated as follows: fit the point set In where the two teeth intersect into a plane Plane, and calculate the mean midpoint Center of the point set In. With Center as the endpoint and the normal vector of the plane Plane as the direction, project it onto the two teeth, and take the sum of the distances between the two points closest to Center after being projected onto the teeth and the midpoint Center as the collision value.

5. The method according to claim 1, characterized in that: The gap value is calculated by constructing KDTree with the vertices of the two tooth meshes respectively, and calculating the distance between the closest points of the two nearest KDTrees as the gap value.

6. The method according to claim 1, characterized in that: In step S3, the value range of the initial value b0 is:

7. The method according to claim 1, characterized in that: In step S3, 8. A computer program product, characterized in that: The invention comprises computer instructions, which, when executed by a processor, cause a computer device to perform the method based on uniform tooth contact value of a dental arch line according to any one of claims 1 to 7.

9. A computer-readable storage medium, characterized in that: Computer-executable instructions are stored thereon, and when a processor executes the computer-executable instructions, the method based on uniform tooth contact value of dental arch line as described in any one of claims 1-7 is implemented.

10. A device based on uniform tooth contact value of dental arch line, characterized by: include: at least one processor; as well as at least one memory in communication with the processor; The memory stores instructions executable by the processor, and the instructions are executed by the processor to enable the device to perform the method based on uniform tooth contact value of dental arch line according to any one of claims 1 to 7.

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