Dental correction system and design method thereof

Abstract

The invention discloses a dental orthodontic system, comprising: a first class of dental instruments designed to include N shell-shaped orthodontic devices for gradually repositioning teeth of a patient from a first tooth layout to a second tooth layout, the first class of dental instruments being divided into K shell-shaped dental instrument groups corresponding to K orthodontic stages, each shell-shaped dental instrument group comprises two or more shell-shaped correctors for progressively moving teeth of a patient from a stage design initial layout of a current correction stage to a stage design target layout; the fine adjustment dental instruments are designed between the adjacent correction stages, each fine adjustment dental instrument comprises M shell-shaped correctors, and the M shell-shaped correctors are designed to progressively position the teeth of the patient to the stage design target layout of the previous correction stage from the actual tooth layout at the end of the previous correction stage, according to the invention, the problem of insufficient expression rate in the correction process can be solved in time by stages. The invention further discloses a corresponding design method of the dental correction system.

Description

Technical Field

[0001] The present invention relates to the technical field of dental orthodontics, and in particular to a dental correction system and a design method thereof. Background Art

[0002] In recent years, in the field of dental orthodontics, shell-shaped dental appliances using bracketless invisible orthodontic technology have become increasingly popular due to their advantages of beauty and convenience when worn. Bracketless invisible orthodontic technology is that patients wear a series of transparent shell orthodontic appliances to move their teeth from the initial position to the target position.

[0003] In existing dental correction schemes, computer programs are generally used to predict the movement of teeth from an initial position to a final position, and a series of dental appliances corresponding to several correction steps are designed and constructed. Each correction step uses a dental appliance, and the patient wears the corresponding dental appliance in each correction step to reposition the teeth from the initial position to the final position. However, the correction ability of the dental appliance in each correction step is often affected by its structure and material, or the force generated by the interaction with the teeth. Each dental appliance will produce a phenomenon of correction force attenuation after the patient wears it for a certain period of time. Therefore, after each correction step or certain correction steps, the actual position of the teeth may deviate from the designed target position, that is, the problem of insufficient expression rate during the correction process occurs. Generally speaking, when this deviation is within an acceptable range, it will not affect the treatment process. However, as the treatment steps progress, the deviation becomes larger and larger, and the teeth that deviate too much from the expected target position may be subjected to greater forces than expected, which may cause discomfort or even pain to the patient. When the deviation increases to a certain extent, it may even make it impossible to wear the braces in subsequent treatment steps. At this time, a new treatment plan needs to be restarted, which affects the effect and cycle of the entire tooth correction. Summary of the invention

[0004] The main purpose of the present invention is to propose a dental correction system and a design method thereof, aiming to solve the problem of insufficient expression rate during the correction process in a timely manner in stages.

[0005] To achieve the above object, an embodiment of the present invention provides a dental correction system, comprising:

[0006] A first type of dental appliance is designed to include N shell-shaped appliances for gradually repositioning a patient's teeth from a first tooth layout to a second tooth layout, the first type of dental appliance is divided into K shell-shaped dental appliance groups corresponding to K treatment stages, each shell-shaped dental appliance group includes two or more shell-shaped appliances, and the two or more shell-shaped appliances are used to gradually move the patient's teeth from a stage-designed initial layout of a current treatment stage to a stage-designed target layout, wherein N>2, K>=2;

[0007] A fine-tuning dental appliance designed between adjacent correction stages, each fine-tuning dental appliance comprising M shell-shaped appliances, wherein the M shell-shaped appliances are designed to progressively position the patient's teeth from an actual tooth layout at the end of a previous correction stage to a stage design target layout of the previous correction stage, wherein M>=1.

[0008] Optionally, the elasticity of each shell-shaped appliance of the fine-tuning dental instrument is the same as the elasticity of each shell-shaped appliance of each shell-shaped dental instrument set.

[0009] Optionally, the elasticity of each shell-shaped appliance of the fine-tuning dental instrument is smaller than the elasticity of each shell-shaped dental appliance of the shell-shaped dental instrument set corresponding to the previous correction stage.

[0010] Optionally, the elasticity of each shell-shaped appliance of the fine-tuning dental instrument gradually decreases with the wearing sequence.

[0011] Optionally, the number M of shell-shaped appliances included in each fine-tuning dental instrument is: 1≤M≤5.

[0012] Optionally, the number M of shell-shaped appliances included in each fine-tuning dental instrument is: 1≤M≤3.

[0013] Optionally, each shell-shaped dental instrument set comprises 5 to 20 shell-shaped appliances.

[0014] Optionally, each shell-shaped dental instrument set comprises 8 to 15 shell-shaped appliances.

[0015] Optionally, each shell-shaped dental instrument set comprises substantially the same number of shell-shaped appliances.

[0016] Optionally, the difference in the number of shell-shaped appliances included in adjacent shell-shaped dental instrument groups is less than or equal to 3.

[0017] To achieve the above object, the present invention also provides a method for designing a dental correction system, comprising the following steps:

[0018] Acquire a first digital model of the jaw and a second tooth layout, and form a series of target digital models of the jaw based on the first digital model of the jaw and the second tooth layout, wherein the series of target digital models of the jaw correspond to a series of orthodontic states of gradually advancing the patient's teeth from the first tooth layout to the second tooth layout;

[0019] designing the first type of dental appliance based on the series of target dental and jaw digital models, the first type of dental appliance comprising N shell-shaped appliances for gradually repositioning the patient's teeth from the first tooth layout to the second tooth layout;

[0020] Determine K-1 fine-tuning design points, wherein the K-1 fine-tuning design points divide the first type of dental appliances including the N shell-shaped appliances into K shell-shaped dental appliance groups corresponding to K correction stages, each shell-shaped dental appliance group includes two or more shell-shaped appliances, and the two or more shell-shaped appliances are used to gradually move the patient's teeth from the initial layout of the stage design of the current correction stage to the target layout of the stage design;

[0021] Acquire a digital model of the actual dental jaw of the patient's teeth at the end of wearing each shell-shaped dental appliance set, wherein the digital model represents the actual dental layout of the patient at the end of the current correction stage;

[0022] Based on the actual tooth-jaw digital model of the stage and the stage design target layout of the current correction stage, M fine-tuned tooth-jaw digital models are designed, and the M fine-tuned tooth-jaw digital models correspond to the tooth correction state of the patient's teeth gradually progressing from the actual tooth layout at the end of the current correction stage to the stage design target layout of the current correction stage;

[0023] Fine-tuned dental appliances are designed based on the M fine-tuned dental jaw digital models, each of which includes M shell-shaped appliances, and the M shell-shaped appliances are designed to progressively position the patient's teeth from the actual tooth layout at the end of the current treatment stage to the target tooth layout designed in the stage.

[0024] Optionally, before the step of designing M fine-tuned digital models of the teeth and jaws based on the actual digital model of the teeth and jaws in the stage and the stage design target layout of the current correction stage, the step further includes:

[0025] Acquire the actual tooth layout of the patient at the end of the current correction stage according to the actual dental digital model of the stage;

[0026] Calculating the offset between the actual tooth layout of the stage and the stage design target layout of the current correction stage;

[0027] When the offset exceeds a first preset threshold, M fine-tuned digital models of the jaws are generated according to the actual digital model of the jaws in the stage and the stage design target layout of the current correction stage.

[0028] Optionally, after the step of calculating the offset between the actual tooth layout of the stage and the stage design target layout of the current correction stage, the method further includes:

[0029] When the offset exceeds a second preset threshold, the position of the next fine-tuning design point is modified to adjust the number of shell-shaped appliances in the shell-shaped dental instrument set corresponding to the next correction stage, wherein the second preset threshold is greater than the first preset threshold.

[0030] Optionally, the second preset threshold is at least greater than or equal to twice the first preset threshold.

[0031] Optionally, when the offset exceeds a second preset threshold, the step of modifying the position of the next fine-tuning design point to adjust the number of shell-shaped appliances in the shell-shaped dental appliance set corresponding to the next correction stage includes:

[0032] Calculating a difference between the offset and the first preset threshold;

[0033] determining a reduction amount of the shell-shaped appliance in the next shell-shaped dental appliance set based on the difference and the first preset threshold;

[0034] The position of the next fine-tuning design point is adjusted according to the determined reduction amount of the shell-shaped appliance in the next shell-shaped dental appliance set.

[0035] Optionally, in the step of adjusting the position of the next fine-tuning design point according to the determined reduction amount of shell-shaped appliances in the next shell-shaped dental instrument group, the reduction of shell-shaped appliances in the next shell-shaped dental instrument group should satisfy that the difference in the number of shell-shaped appliances in the next shell-shaped dental instrument group and the shell-shaped appliances in the adjacent previous shell-shaped dental instrument group is less than or equal to 3, or the number of shell-shaped appliances in the next shell-shaped dental instrument group is greater than or equal to 5.

[0036] Optionally, when the offset exceeds a first preset threshold, generating M fine-tuned digital models of the jaws according to the actual digital model of the jaws in the stage and the stage design target layout of the current correction stage, including:

[0037] For each tooth or each determined characteristic tooth, determining in turn whether each offset component of the current tooth exceeds the corresponding first preset threshold, the offset between the actual tooth layout at the stage and the target layout designed at the stage includes the first to third offset components corresponding to the X-axis, Y-axis, and Z-axis offsets and the fourth offset component corresponding to the angle offset;

[0038] When any offset component of a tooth exceeds a corresponding first preset threshold, it is determined that the current tooth needs to be fine-tuned;

[0039] When any tooth needs to be fine-tuned, M fine-tuned tooth-jaw digital models are generated based on the actual tooth-jaw digital model at that stage and the target layout designed at that stage.

[0040] Optionally, when the offset exceeds a first preset threshold, generating M fine-tuned digital models of the jaws according to the actual digital model of the jaws in the stage and the stage design target layout of the current correction stage, including:

[0041] Determine several key offset components among the offset components of each tooth, wherein the offset between the actual tooth layout at the stage and the target layout designed at the stage includes first to third offset components corresponding to X-axis, Y-axis, and Z-axis offsets and a fourth offset component corresponding to an angle offset;

[0042] Determining in turn for each tooth or each determined characteristic tooth whether each key offset component of the current tooth exceeds a corresponding first preset threshold;

[0043] When any key offset component of a certain tooth exceeds the corresponding first preset threshold, it is determined that the current tooth needs to be fine-tuned;

[0044] When any tooth needs to be fine-tuned, M fine-tuned tooth-jaw digital models are generated based on the actual tooth-jaw digital model at that stage and the target layout designed at that stage.

[0045] Optionally, when the offset exceeds a first preset threshold, generating M fine-tuned digital models of the jaws according to the actual digital model of the jaws in the stage and the stage design target layout of the current correction stage, including:

[0046] For each tooth or each determined characteristic tooth, normalizing each offset component of the current tooth in turn to obtain each normalized offset component, wherein the offset between the actual tooth layout at the stage and the target layout designed at the stage includes first to third offset components corresponding to the offsets of the X-axis, Y-axis, and Z-axis and a fourth offset component corresponding to the angle offset;

[0047] Obtaining a comprehensive offset based on each normalized offset component;

[0048] Determining whether the current tooth needs fine adjustment based on the comprehensive offset and the corresponding first preset threshold;

[0049] When any tooth needs to be fine-tuned, M fine-tuned tooth-jaw digital models are generated based on the actual tooth-jaw digital model at that stage and the target layout designed at that stage.

[0050] Optionally, when the offset exceeds a first preset threshold, generating M fine-tuned digital models of the jaws according to the actual digital model of the jaws at the stage and the stage design target layout of the current correction stage, further comprising:

[0051] Determining the teeth that need to be fine-tuned according to the offset of each tooth in the patient's dentition and the corresponding first preset threshold;

[0052] Count the number of teeth in the patient's dentition that need fine-tuning;

[0053] Whether fine-tuning is required is determined based on the statistically obtained ratio of the number of teeth that need fine-tuning to the total number of teeth in the patient's dentition.

[0054] Compared with the prior art, the dental correction system and design method of the present invention have the following beneficial effects:

[0055] 1. The present invention first designs a first type of dental device for gradually repositioning the first tooth layout of the patient's teeth to the second tooth layout based on the first tooth layout and the second tooth layout of the teeth, then divides the N correction steps corresponding to the first type of dental device into K consecutive correction stages, and designs a fine-tuning dental device between adjacent correction stages to eliminate the deviation between the actual tooth layout in the previous correction stage caused by the influence of the structure and material of the shell-shaped appliance or the influence of the force generated by the interaction with the teeth and the stage design target layout of the previous correction stage, so that the patient's teeth are convenient to wear the appliance in the next correction stage after wearing the fine-tuning dental device, and reduce the discomfort of wearing the appliance caused by the deviation;

[0056] 2. The present invention obtains the actual tooth layout of the current stage at the end of each correction stage, and determines whether to start the design of fine-tuning dental instruments according to the offset between the actual tooth layout and the stage design target layout designed for the current correction stage. The design of fine-tuning dental instruments needs to be started only when the offset between the actual tooth layout and the stage design target layout designed for the current correction stage is greater than a set first preset threshold value, thereby avoiding starting the design of fine-tuning dental instruments when the offset between the actual tooth layout and the stage design target layout designed for the current correction stage is very small, thereby causing unnecessary extension of the correction period and increase in correction costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] One or more embodiments are exemplarily described by the pictures in the corresponding drawings, and these exemplary descriptions do not constitute limitations on the embodiments.

[0058] Figure 1 is a system architecture diagram of a dental correction system in one embodiment of the present application;

[0059] Figure 2 A schematic diagram of a shell-shaped dental instrument set 101 in one embodiment of the present application;

[0060] Figure 3 Schematic diagram of fine-tuning a dental instrument 102 according to an embodiment of the present application

[0061] Figure 4 This is a flowchart of a method for designing a dental correction system in another embodiment of the present application;

[0062] Figure 5 This is a flowchart of the steps of a design method of a dental correction system in another embodiment of the present application. DETAILED DESCRIPTION

[0063] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the embodiments of the present application will be described in detail below in conjunction with the accompanying drawings. However, it will be appreciated by those skilled in the art that in the present application, many technical details are proposed in order to enable the reader to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical scheme claimed in the present application can also be implemented. The division of the following embodiments is for the convenience of description, and the specific implementation of the present application should not be construed as any limitation, and the various embodiments can be combined and referenced with each other under the premise of no contradiction.

[0064] In order to simplify the drawings, only the parts related to the present invention are schematically shown in each figure, and they do not represent the actual structure of the product. In addition, in order to simplify the drawings and facilitate understanding, in some figures, only one of the parts with the same structure or function is schematically drawn or marked. In this article, "one" not only means "only one", but also means "more than one".

[0065] The "anterior tooth area" and "posterior tooth area" mentioned in various embodiments of the present application are defined according to the classification of teeth in the second edition of "Introduction to Stomatology" published by Peking University Medical Press, pages 36-38. The posterior tooth area includes premolars and molars, which are displayed as teeth 4-8 by the FDI marking method. The anterior tooth area is displayed as teeth 1-3 by the FDI marking method. The teeth in the anterior tooth area include central incisors, lateral incisors and canines. In addition, for the teeth in the deciduous tooth stage, the "anterior tooth area" and "posterior tooth area" are defined according to the classification of deciduous teeth in the second edition of "Introduction to Stomatology" published by Peking University Medical Press, pages 40-41, including three categories: deciduous incisors, deciduous canines and deciduous molars. The anterior tooth area includes deciduous incisors and deciduous canines, wherein the deciduous incisors include deciduous central teeth and deciduous lateral incisors, and the posterior tooth area includes deciduous molars, wherein the deciduous molars include first deciduous molars and second deciduous molars.

[0066] As can be seen from the background technology, for the current invisible dental orthodontic system, the correction ability of the dental appliance in each correction step will be affected by its structure and material, or the force generated by the interaction with the teeth. The dental appliance will produce a phenomenon of correction force attenuation after the patient wears it for a certain period of time. Therefore, after each correction step or some correction steps, the actual position of the teeth may deviate from the designed target position, that is, the problem of insufficient expression rate during the correction process occurs. Generally speaking, when this deviation is within an acceptable range, it will not affect the correction process. However, as the correction steps proceed, when the deviation becomes larger and larger, the teeth that deviate too much from the expected target position may be subjected to a greater force than expected, which will cause discomfort to the patient or even cause pain; further, when the deviation increases to a certain extent, it may even cause the braces in the subsequent correction steps to be unable to be worn, and a new correction plan must be restarted, thereby affecting the effect and cycle of the entire dental correction.

[0067] Based on this, the present invention proposes a dental correction system, comprising: a first type of dental instrument, which is designed to include N shell-shaped appliances for gradually repositioning a patient's teeth from a first tooth layout to a second tooth layout, wherein N>2, the first type of dental instrument is divided into K shell-shaped dental instrument groups corresponding to K correction stages, each shell-shaped appliance corresponds to a correction step, and each correction stage includes at least two or more correction steps, that is, each shell-shaped dental instrument group includes two or more shell-shaped appliances, and the two or more shell-shaped appliances are used to gradually move the patient's teeth from the initial layout of the stage design of the current correction stage to the target layout of the stage design, wherein K>=2; and a fine-tuning dental instrument designed between adjacent correction stages, that is, K-1 fine-tuning dental instruments are designed corresponding to the K correction stages, each fine-tuning dental instrument includes M shell-shaped appliances, and the M shell-shaped appliances are The invention is designed to progressively position the patient's teeth from the actual tooth layout at the end of the previous correction stage in the adjacent correction stages to the stage design target layout of the previous correction stage, wherein M>=1. The invention mainly designs a first type of dental device based on the first tooth layout and the second tooth layout of the teeth to gradually reposition the patient's teeth from the first tooth layout to the second tooth layout, and then divides the N correction steps corresponding to the first type of dental device into K consecutive correction stages, and designs fine-tuning dental devices between adjacent correction stages to eliminate the deviation between the actual tooth layout in the previous correction stage caused by the influence of the structure and material of the shell-shaped orthodontic device, or the influence of the force generated by the interaction with the teeth, and the stage design target layout of the previous correction stage, so that the patient's teeth can be conveniently worn by the orthodontic device in the next correction stage after wearing the fine-tuning dental device, thereby reducing the discomfort of wearing the orthodontic device caused by the deviation.

[0068] The implementation details of the dental correction system described in this application will be specifically described below in conjunction with specific embodiments. The following content is only the implementation details provided for ease of understanding and is not necessary for implementing this solution.

[0069] An exemplary embodiment of the present application provides a dental correction system, which includes a first type of dental instrument designed to gradually reposition a patient's teeth from a first tooth layout to a second tooth layout, wherein the first tooth layout can be the initial layout of the patient at the beginning of the correction, or the tooth layout after a period of correction, and the second tooth layout can be the final tooth layout of the patient's correction, or the stage target layout of the correction to a certain stage, and the first type of dental instrument includes N shell-shaped appliances that are worn successively, N>=2, and the number of shell-shaped appliances used in the dental correction system of the present application is not constant. Generally speaking, the correction process of the dental correction system requires at least 4 correction steps, sometimes 20 correction steps, and for some complex cases, 40 or even more correction steps are required, and each correction step corresponds to at least one shell-shaped appliance, that is, the first The number of correction steps included in the dental appliance can be N or less than N. Each shell-shaped appliance includes a shell for accommodating and positioning teeth. The N shell-shaped appliances have different geometric shapes for successively positioning teeth from an initial tooth state corresponding to the correction step to a cavity for accommodating teeth in a desired tooth state. The N shell-shaped appliances are divided into K shell-shaped dental appliance groups 101 according to the wearing order. Each shell-shaped dental appliance group 101 corresponds to a correction stage, that is, the continuous N shell-shaped appliances are divided into K shell-shaped dental appliance groups 101 corresponding to K correction stages. The correction steps in each correction stage are continuous correction steps, and the last correction step of the previous correction stage in adjacent correction stages and the first correction step of the next correction stage in adjacent correction stages are adjacent correction steps. Each shell-shaped dental appliance group 101 includes at least two or more shell-shaped appliances 101a, such as Figure 2As shown, the two or more shell-shaped orthodontic appliances 101a are used to gradually move the patient's teeth from the initial layout of the stage design of the current correction stage to the target layout of the stage design of the current correction stage. For example, for the ith correction stage, the corresponding one is the ith group of shell-shaped dental instrument sets. The shell-shaped orthodontic appliances included in the ith group of shell-shaped dental instrument sets are used to gradually move the patient's teeth from the initial layout of the stage design of the ith correction stage to the target layout of the stage design of the ith correction stage. Specifically, when designing the dental correction system of the present invention, a first tooth-jaw digital model corresponding to the first tooth layout of the patient and a second tooth layout are obtained to form a series of gradually progressive tooth-jaw digital models. A series of progressive dental and jaw digital models correspond to a dental correction state in which the patient's teeth are gradually changed from a first tooth layout to a second tooth layout. Specifically, the initial layout of the stage design of the i-th correction stage refers to the dental correction state represented by the dental and jaw digital model of the last correction step of the i-1-th correction stage, and the stage design target layout of the i-th correction stage refers to the dental correction state represented by the dental and jaw digital model of the last correction step of the i-th correction stage; a fine-tuning dental appliance 102 designed between adjacent correction stages. For K correction stages, the dental correction system of the present invention has K-1 fine-tuning dental appliances 102, each of which includes M shell-shaped appliances 102a, such as Figure 3 As shown, each shell-shaped appliance 102a includes a shell for accommodating and positioning teeth, and the M shell-shaped appliances 102a have cavities of different geometric shapes for successively positioning the teeth from the actual tooth layout at the end of the previous treatment stage to the stage design target layout of the previous treatment stage. For example, for the fine-tuning dental device 102 designed between the Kth treatment stage and the K+1th treatment stage, it is designed to gradually move the patient's teeth from the actual tooth layout at the end of the Kth treatment stage to the stage design target layout of the Kth treatment stage, that is, the stage design target layout of the Kth treatment stage is the tooth treatment state represented by the digital model of the dental jaw at the last treatment step of the Kth treatment stage.

[0070] Specifically, if too few correction steps are designed for each correction stage, and the correction time of each correction stage is too short, the deviation between the actual tooth layout and the designed stage design target layout will be relatively small. The small deviation is not enough to affect the wearing of the subsequent shell-shaped orthodontic appliance. In this case, there is no need to design a fine-tuning dental instrument 102 for fine-tuning between the current correction stage and the next correction stage. If too many correction steps are designed for each correction stage, and the correction time of the current correction stage is too long, the deviation between the actual tooth layout and the designed stage design target layout will be too large, which may cause the subsequent orthodontic appliance to be unable to be worn. At this time, the accumulated deviation formed by a certain intermediate correction step in the current correction stage may have affected the wearing of the shell-shaped orthodontic appliance that is worn later in the current correction stage. Therefore, in order to avoid this situation, the number of shell-shaped orthodontic appliances contained in the shell-shaped dental instrument group corresponding to each correction stage should be reasonably set. In each embodiment of the present invention, the number of shell-shaped orthodontic appliances contained in each shell-shaped dental instrument group is It can be determined based on the experience of doctors or designers. In some embodiments, the number of shell-shaped orthodontic appliances included in each shell-shaped dental instrument group 101 of the first type of dental instruments is 5 to 20, and the number of shell-shaped orthodontic appliances in the shell-shaped dental instrument group is less than 5. On the one hand, the correction time of 5 correction steps is short, and the accumulated deviation may be too small to require the design of fine-tuning dental instruments. On the other hand, the design of fine-tuning dental instruments too frequently causes excessive extension of the dental correction cycle. If the number of shell-shaped orthodontic appliances is greater than 20, the correction time of the current correction stage may be too long, and the deviation may be too large in the middle correction step, which will not only affect the wearing of the orthodontic appliances in the subsequent correction stage, but also affect the wearing treatment of the orthodontic appliances in the correction step with a later wearing order in the current correction stage; further, in some preferred embodiments, the number of shell-shaped orthodontic appliances included in each shell-shaped dental instrument group of the first type of dental instruments is 8 to 15, and more preferably, the number of shell-shaped orthodontic appliances in the shell-shaped dental instrument group is 10.

[0071] In various embodiments of the present invention, for the efficiency and cost considerations of appliance preparation, the same diaphragm is often used to prepare each shell-shaped appliance in the first category of dental instruments. In this case, considering that the appliances prepared from the same diaphragm have substantially the same correction performance, in the K correction stages of the first category of dental instruments, the number of shell-shaped appliances included in each correction stage is substantially the same, and the substantially the same means that the number of shell-shaped appliances included in each correction stage of at least the first K-1 correction stages is the same, and the last correction stage may contain the same number of shell-shaped appliances as each correction stage of the first K-1 correction stages, or may be different from the number of shell-shaped appliances included in each of the first K-1 correction stages due to insufficient number of remaining appliances. For example, when the shell-shaped appliances included in the designed first category of dental instruments are When the number N is 40, the number of braces included in each correction stage can be 10. When the number N of shell-shaped braces included in the designed first type of dental instrument is 48, the number of braces included in the first four correction stages is 10, and the number of braces included in the last correction stage is 8. Of course, as the correction process progresses, the actual tooth correction state of each correction stage changes, the number of shell-shaped appliances included in each correction stage may also be different. For example, the number of shell-shaped appliances included in each correction stage may gradually increase or decrease with the correction process, or it may be different determined by the doctor or designer based on the actual situation of the patient for personalized design. However, according to experience, the difference in the number of shell-shaped appliances included in adjacent shell-shaped dental instrument groups generally does not exceed 3.

[0072] Since the fine-tuning dental instrument 102 is only used to compensate for the deviations generated during the correction process in each correction stage, generally speaking, the deviation must be smaller than the designed target movement amount of the correction stage. Therefore, the number of appliances included in the fine-tuning dental instrument 102 should be less than the number of shell-shaped appliances included in each correction stage. In some embodiments, the number M of shell-shaped appliances included in each fine-tuning dental instrument 102 is: 1≤M≤5. Considering that if the fine-tuning dental instrument includes too many shell-shaped appliances, the correction period will be too long and will not be accepted by the patient, and the increase in the number of appliances will also result in an increase in costs, in some preferred implementations, the number M of shell-shaped appliances included in each fine-tuning dental instrument is preferably limited to 3 or less.

[0073] In some embodiments, also based on the efficiency and cost considerations of appliance preparation, the elasticity of each shell-shaped appliance of each fine-tuning dental instrument 102 can be the same as the elasticity of each shell-shaped appliance of each shell-shaped dental instrument group. Since the elasticity of the shell-shaped appliance of each correction step in the first category of dental instruments is the same as that of each fine-tuning correction step in the fine-tuning dental instrument, the patient will not feel discomfort caused by the elasticity of the appliance. In other embodiments, since the number of shell-shaped appliances included in each fine-tuning dental instrument should not be too large, in order to allow the patient's teeth to be moved as much as possible to the stage design target layout of the previous correction stage after the correction by the fine-tuning dental instrument, the elasticity of each shell-shaped appliance of each fine-tuning dental instrument is less than the elasticity of each shell-shaped dental appliance of the shell-shaped dental instrument group corresponding to the previous correction stage. The shell with less elasticity can provide a greater tooth correction force to improve the expression rate of the fine-tuning correction stage.

[0074] In some embodiments, the elasticity of the shell-shaped appliance in each fine-tuning dental instrument is less than the elasticity of each shell-shaped dental appliance in the previous correction stage, and the elasticity of each shell-shaped appliance in the fine-tuning dental instrument gradually decreases with the wearing sequence. The design of gradually decreasing elasticity can make the correction force exerted on the patient's teeth in each fine-tuning correction step gradually increase, so that the patient can easily adapt to the gradual increase in correction force and reduce the patient's discomfort.

[0075] In each embodiment of the present invention, the elasticity of the shell-shaped appliance mainly refers to the elasticity of the diaphragm used to prepare the shell-shaped appliance. The elasticity of the diaphragm used to prepare the shell-shaped appliance is related to many factors, such as the thickness of the diaphragm and the elastic modulus of the diaphragm material. Generally speaking, when the thickness of the diaphragm is the same, the greater the elastic modulus of the diaphragm material, the greater the dental correction force generated. For the same material, the thickness of the diaphragm will also affect the magnitude of the correction force generated; when the diaphragm material is the same, the greater the thickness of the diaphragm, the greater the dental correction force generated. Therefore, for each shell-shaped appliance of the fine-tuning dental instrument, based on the thickness of the diaphragm and the selection of the material, the elasticity of each shell-shaped appliance of the fine-tuning dental instrument can be less than the elasticity of each shell-shaped dental appliance in the previous correction stage, or the elasticity is less than the elasticity of each shell-shaped dental appliance in the previous correction stage, and the elasticity gradually decreases with the wearing order.

[0076] It should be noted that Figure 1-Figure 3 The structure of the dental orthodontic system of the present invention is illustrated by taking a single-jaw appliance as an example, but it should be understood that the shell-shaped appliance corresponding to each correction step may also be a double-jaw appliance, that is, including both a maxillary appliance and a mandibular appliance, and the present invention is not limited to this.

[0077] like Figure 4 As shown, in other embodiments of the present invention, a method for designing a dental correction system is also provided, comprising:

[0078] Step S1, obtaining a first jaw digital model representing a first tooth layout and a second tooth layout, and forming a series of target jaw digital models based on the first jaw digital model and the second tooth layout, wherein the series of target jaw digital models correspond to a series of orthodontic states of gradually and progressively moving the patient's teeth from the first tooth layout to the second tooth layout.

[0079] Specifically, the first dental digital model can be the dental digital model initially acquired when the patient starts the correction design, or it can be the dental digital model obtained after the patient has been corrected for a period of time, and the second tooth layout can be the final target dentition layout corresponding to the patient's correction, or it can be the stage target dentition layout corresponding to the patient's correction. The above series of target dental digital models are computer digital models used to guide the manufacture of tooth models, and the tooth model manufactured according to each target dental digital model is a three-dimensional model of the tooth state (also called tooth arrangement). The dental correction state includes a series of corrected tooth states, and each tooth state corresponds to a target dental digital model. Each tooth state includes the geometric shapes of a number of teeth corresponding to a correction step and the positional relationship between the teeth.

[0080] In some specific embodiments, a physical tooth model is first made according to the patient's current tooth state, or the state of the teeth and their surrounding tissues (such as gums and facial soft tissues) (for example, a plaster tooth model is made by taking an impression), and then the physical tooth model is scanned to obtain a first tooth-jaw digital model (corresponding to the basic tooth state). Of course, the image of the teeth, or the teeth and their surrounding tissues, can also be directly obtained by optical scanning, three-dimensional photography, three-dimensional video or medical CT scanning, and the first tooth-jaw digital model is generated by computer processing, and the patient's first tooth layout can be obtained according to the first tooth-jaw digital model.

[0081] Then, the patient's current correction goal, that is, the second tooth layout, is obtained, and the computer system generates a series of intermediate steps for the patient's dentition from the first tooth layout to the second tooth layout based on the first tooth layout and the second tooth layout. The generation process needs to consider the order of tooth movement, the amount of movement in each step, the force state of the teeth, the collision state between teeth, etc. These movement steps determine how the teeth gradually move each tooth during the treatment process to achieve the final correction goal. For the specific step-by-step process, reference can be made to the step-by-step method for tooth correction in patent 202110497074.0, wherein the series of intermediate steps correspond to a series of target dental digital models, that is, the series of target dental digital models correspond to a series of dental correction states in which the patient's teeth are gradually moved from the first tooth layout to the second tooth layout, and the series of dental correction states reflects the favorable changes in the tooth structure or arrangement after a series of correction steps are performed on the first tooth layout. Generally speaking, the above correction process includes at least one correction step (for example, 20-40 correction steps), each correction step corresponds to a tooth correction state, and each tooth correction state corresponds to a tooth digital data model, so a series of target jaw digital models can be obtained and stored by the computer system. Of course, in addition to the above-mentioned implementation method of first obtaining the patient's second tooth layout, and then performing intermediate process steps to obtain a series of target jaw digital models, other methods can also be used, such as using the target search method to limit the position of each tooth in the mobile dentition according to the physiological characteristics of the teeth, and detect whether the moved dentition meets the characteristics of the correction target. When it is determined that it does not meet the characteristics, some of the teeth are adjusted until all teeth meet the correction target.

[0082] Step S2, designing a first type of dental appliance based on the series of target dental digital models, wherein the first type of dental appliance includes N shell-shaped appliances for gradually repositioning the patient's teeth from a first tooth layout to a second tooth layout.

[0083] Specifically, a physical target tooth model (i.e., a positive mold of a shell-shaped appliance) is generated according to the series of target dental digital model models, that is, a corresponding physical tooth model is manufactured according to a target dental digital model model of a series of target dental digital model models. In various embodiments of the present invention, a positive mold of a dental appliance can be manufactured based on a rapid prototyping process. Rapid prototyping technology can be divided into the following typical prototyping processes: Stereolithography Apparatus (SLA), Laminated Object Manufacturing (LOM), Selected Laser Sintering (SLS), Fused Deposition Modeling (FDM), Three Dimensional Printing (3DP), etc.

[0084] After obtaining the physical tooth model (positive mold) of each correction step by rapid prototyping, the first type of dental appliance can be obtained based on the series of physical tooth models, for example, by using a hot pressing forming device, a positive pressure film pressing technology is used to press an appliance membrane composed of a transparent polymer material (elastic polymer, such as polycarbonate) on the above physical tooth model to form a shell, thereby making a series of shell-shaped appliances. Of course, the method of obtaining a shell-shaped appliance based on the target jaw digital model is not limited to hot pressing molding, and other methods can also be used. The present invention is not limited to this. That is, the first type of dental appliance obtained based on the target jaw digital model includes N shell-shaped appliances that gradually reposition the patient's teeth from the first tooth layout to the second tooth layout.

[0085] Step S3, determining K-1 fine-tuning design points, wherein the K-1 fine-tuning design points divide the first type of dental appliances including the N shell-shaped appliances into K shell-shaped dental appliance groups corresponding to K treatment stages, each shell-shaped dental appliance group includes two or more shell-shaped appliances, and the two or more shell-shaped appliances are used to gradually move the patient's teeth from the initial layout of the stage design of the current treatment stage to the target layout of the stage design.

[0086] The fine-tuning design point refers to the time point at the end of the last correction step of each correction stage of the design. For the i-th fine-tuning design point, the shell-shaped dental instrument group corresponding to the i-th correction stage is located before the i-th fine-tuning design point, and the shell-shaped dental instrument group corresponding to the i+1-th correction stage is located after the i-th fine-tuning design point.

[0087] Specifically, after obtaining N shell-shaped appliances that gradually and progressively move the patient's teeth from the first tooth layout to the second tooth layout, it is necessary to determine how many steps of correction the deviation between the actual layout of the teeth and the designed stage design target layout may increase the discomfort of the patient wearing the subsequent appliances, thereby determining each fine-tuning design point. In various embodiments of the present invention, the position of each fine-tuning design point can be designed by a doctor or designer based on their experience. In some embodiments, by designing the fine-tuning design point, the number of shell-shaped appliances in each correction stage is designed to be 5 to 20. In some preferred embodiments, by designing the fine-tuning design point, the number of shell-shaped appliances in each correction stage is designed to be 8 to 15, for example, the number of shell-shaped appliances in each correction stage is designed to be 10. In each correction stage of the design, the number of shell-shaped appliances included in each correction stage can be roughly the same, or the number of shell-shaped appliances in each correction stage can be different, but generally speaking, the difference in the number of shell-shaped appliances included in adjacent shell-shaped dental instrument groups generally does not exceed 3.

[0088] Step S4, obtaining a digital model of the actual teeth and jaws of the patient's teeth at the end of wearing each shell-shaped dental appliance set, wherein the digital model of the actual teeth and jaws at the end of the current correction stage of the patient is represented.

[0089] In various embodiments of the present invention, the actual dental and jaw digital model of the stage can be obtained by converting the negative mold in the mouth of silicone rubber into a positive mold and then scanning it, or by intraoral scanning, which will not be repeated here. The actual dental and jaw digital model of the stage corresponds to the actual dental treatment state of the patient at the end of the current treatment stage. For example, for the first treatment stage, it is necessary to obtain the actual dental and jaw digital model of the patient's teeth at the end of the treatment stage, and the actual dental and jaw digital model of the stage represents the dental treatment state at the end of the first treatment stage.

[0090] Step S5, based on the actual jaw digital model of the stage and the stage design target layout designed for the current treatment stage, design M fine-tuned jaw digital models, and the M fine-tuned jaw digital models correspond to the dental treatment state of gradually and progressively moving the patient's teeth from the actual tooth layout at the end of the current treatment stage to the stage design target layout designed for the current treatment stage.

[0091] Similarly, the computer system automatically forms several stage digital models of the teeth and jaws according to the actual dental and jaw digital model of the current treatment stage and the stage design target layout designed for the current treatment stage. The several stage digital models of the teeth and jaws correspond to several dental treatment states of gradually and progressively moving the patient's teeth from the actual tooth layout of the current treatment stage to the stage design target layout designed for the current treatment stage. The several dental treatment states reflect the favorable changes in the tooth structure or arrangement after the actual tooth layout of the current treatment stage is subjected to several fine-tuning treatment steps again. In some embodiments, the fine-tuning treatment steps of the fine-tuning dental instrument include 1 to 5 treatment steps. Considering that if the fine-tuning dental instrument contains too many shell-shaped appliances, the treatment cycle will be too long and unacceptable to the patient, and the increase in the number of appliances will also increase the cost. In some preferred embodiments, the fine-tuning treatment steps contained in each fine-tuning dental instrument are preferably limited to 3 or less, that is, the number M of the M fine-tuning digital models of the teeth and jaws is less than or equal to 3.

[0092] Step S6, designing fine-tuned dental appliances based on the M fine-tuned dental digital models, each of which includes M shell-shaped orthodontic appliances, and the M shell-shaped orthodontic appliances are designed to progressively position the patient's teeth from the actual tooth layout at the end of the current treatment stage to the stage design target tooth layout of the current treatment stage.

[0093] Similarly, a physical target tooth model (i.e., a positive mold of a shell-shaped appliance) is generated based on the M fine-tuning digital models of the jaws, and the positive mold of the tooth appliance is manufactured based on a rapid prototyping process. After the physical tooth model (positive mold) of each fine-tuning correction step is obtained by rapid prototyping, the M shell-shaped appliances of the fine-tuning dental instrument can be obtained based on the physical tooth model of each fine-tuning correction step, for example, by means of a hot pressing forming device, through positive pressure laminating technology, an appliance membrane composed of a transparent polymer material (elastic polymer, such as polycarbonate) is pressed on the above-mentioned physical tooth model to form a shell, thereby obtaining M shell-shaped appliances.

[0094] The design of fine-tuning dental instruments actually prolongs the patient's treatment period and inevitably increases the patient's expenses. This is often acceptable on the basis that it can significantly improve the treatment effect. However, in the actual treatment process, if the deviation between the actual tooth layout at the end of a certain treatment stage and the designed stage target layout is small and does not affect the subsequent wearing of the orthodontic appliance, then if you still choose to design fine-tuning dental instruments, it will not only prolong the treatment period and increase the expenses, but also have no significant improvement in the treatment effect, which is obviously unnecessary.

[0095] Therefore, in some embodiments, Figure 5As shown, before designing M fine-tuned digital models of the jaws based on the actual digital model of the jaws in the stage and the stage design target layout designed in the current correction stage, the following steps are also included:

[0096] Step S401, obtaining the actual tooth layout of the patient at the end of the current correction stage according to the actual dental and jaw digital model of the stage;

[0097] S402, calculating the offset between the actual tooth layout of the stage and the stage design target layout of the current correction stage;

[0098] S403, when the offset exceeds the first preset threshold, the process proceeds to step S5, that is, generating M fine-tuned digital models of the jaws according to the actual digital model of the jaws in the stage and the stage design target layout of the current correction stage.

[0099] In this embodiment, the actual tooth layout of the patient's teeth at the end of the current correction stage can be obtained based on the actual tooth and jaw digital model of the stage. The current tooth coordinates of each tooth at the end of the current correction stage can be obtained according to the actual tooth layout of the stage. The current tooth coordinates include tooth position coordinates and angle coordinates. At the same time, the stage design target layout of the current correction stage can be obtained according to the target tooth and jaw digital model corresponding to the last correction step of the current correction stage. The stage design tooth coordinates of each tooth are obtained according to the stage design target layout. Taking tooth No. 23 as an example, it is assumed that its current tooth coordinates at the end of the current correction stage are (x23', y23', z23', θ23'), where x2 3', y23', z23', θ23' are the X-axis, Y-axis, Z-axis coordinates and angular coordinates in the local coordinate system of the tooth respectively; the stage design tooth coordinates of tooth No. 23 are (x23, y23, z23, θ23), x23, y23, z23, θ23 are the X-axis, Y-axis, Z-axis coordinates and angular coordinates in the local coordinate system of the tooth respectively, and the offset of the tooth in the current correction stage is calculated according to the current coordinates of the tooth (x11', y11', z11', θ11') and the stage design tooth coordinates (x11, y11, z11, θ11), and the offset includes the first to third offset components of the X-axis, Y-axis, and Z-axis and the fourth offset component of the angle θ.

[0100] For a patient's dentition, there are generally multiple teeth. During the correction process, there will be a corresponding offset between the actual tooth layout of each tooth and the target layout of the designed stage, and the offset of each tooth is often different. Therefore, it is necessary to determine how to judge whether fine-tuning the design is needed based on the offset.

[0101] In some embodiments, considering that the offset of each tooth may affect the wearing of the orthodontic appliance, it is possible to determine whether the patient's dentition needs fine-tuning design based on the offset of each tooth. Specifically, firstly, the offset between the actual tooth layout at the end of the current correction stage of each tooth and the stage design target layout is calculated (the offset includes the first to fourth offset components), and then based on the offset of each tooth and the corresponding first preset threshold, it is determined whether the current tooth needs fine-tuning. When the offset of a certain tooth is greater than the corresponding first preset threshold, it is determined that it needs fine-tuning. When there are teeth that need fine-tuning, step S5 is entered to design the fine-tuning process. That is to say, as long as there are teeth that need fine-tuning in the patient's dentition, step S5 is entered to perform fine-tuning design; in other embodiments, considering that some teeth A small offset of teeth in a certain position will have little effect on the wearing of the braces in the subsequent occlusal fine-tuning stage, while a small offset of teeth in some positions will affect the wearing of the subsequent braces. Therefore, the teeth whose deviation between the actual tooth position and the tooth position of the stage design target layout has a greater impact on the wearing of the subsequent braces can be first determined as feature teeth, and whether each feature tooth needs fine-tuning is determined based on the offset of each feature tooth. If it is determined that a feature tooth needs fine-tuning, then step S5 is entered for fine-tuning design. Specifically, the offset of each feature tooth (including the first to fourth offset components) is calculated, and whether it needs fine-tuning is determined based on the offset of each feature tooth and the corresponding first preset threshold. When the offset of a feature tooth is greater than the corresponding first preset threshold, step S5 is entered for fine-tuning process design. In this embodiment, the determination of the feature teeth can be specified by the doctor or designer based on their own experience. Of course, the determination of the feature teeth can also be determined based on the current tooth coordinates of the patient's teeth and the stage design tooth coordinates using the principal component analysis method, which will not be repeated here.

[0102] As described above, at least four offset components, namely the first to fourth offset components, can be obtained for each tooth. Different offset components correspond to different first preset thresholds. The judgment can be fine-tuned based on each offset component separately or after fusing each offset component. In some embodiments, it can be determined whether each offset component of each tooth or each characteristic tooth exceeds the corresponding first preset threshold value. As long as there is an offset component that exceeds the corresponding first preset threshold value, it is determined that the current tooth needs fine-tuning, and it is necessary to enter step S5 to design the fine-tuning process. For example, for tooth No. 23, if the calculated offset component of its angle, that is, the fourth offset component is greater than its corresponding first preset threshold value (for example, 0.5°), it is determined that the current tooth needs fine-tuning, and it is determined that it is necessary to enter step S5 to perform fine-tuning design; in other embodiments, considering that different offset components have different effects on the subsequent wearing of shell-shaped orthodontic appliances, several offset components can also be determined as key offset components. At this time, for each tooth or each characteristic tooth, it is not necessary to judge each offset component, but only to judge whether the key offset component exceeds the corresponding first preset threshold value. As long as there is a key offset component of the current tooth that exceeds the corresponding first preset threshold value, it is determined that the current tooth needs fine-tuning, and then enter step S5 to perform fine-tuning design. In this embodiment, the key offset components can be determined manually by doctors or designers based on experience, or by using principal component analysis to perform principal component analysis on the first to third offset components of the X-axis, Y-axis, and Z-axis of each tooth and the fourth offset component of the angle θ to determine the key offset components.

[0103] However, whether it is the separate judgment of each offset component or the judgment based on the key offset component after determining whether the tooth needs fine-tuning, the results of each offset component are used to judge whether fine-tuning is needed in isolation, which is likely to result in inaccurate judgment results. Therefore, in some other embodiments, for each tooth, it is also possible to determine whether fine-tuning is required based on a comprehensive consideration of the results of each offset component. In some examples, the results of each offset component can be weighted and comprehensively calculated to obtain the comprehensive offset of the current tooth. However, since different offset components have different dimensions, the results of each offset component cannot be directly weighted. Therefore, in this example, for the offset components under different dimensions, they need to be normalized and then weighted summed to obtain the comprehensive offset. The calculated comprehensive offset is compared with the set first preset threshold. If it is greater than the first preset threshold, it is determined that the current tooth needs fine-tuning, wherein normalization can be achieved by designing corresponding normalization parameters for each offset component. In some preferred embodiments, the normalization parameters of different offset components can select the target offset under the corresponding movement mode; specifically, each offset component can be normalized according to the following expression: Pi=Mi / Ni, wherein Pi is the normalized result of each offset component, Mi is the value of different offset components, and Ni is the normalization parameter corresponding to each offset component.

[0104] In addition, in the actual correction process, when the number of teeth whose offset exceeds the corresponding first preset threshold is relatively small, the difference between the actual tooth layout at that stage and the target layout of the stage design may not affect the wearing of subsequent orthodontic appliances, and there is no need for fine-tuning design at this time to minimize the correction cycle and correction cost. Therefore, in other embodiments, after judging whether each tooth needs fine-tuning, it is necessary to count the number of teeth that need fine-tuning. When the proportion of the number of teeth that need fine-tuning to the total number of teeth is greater than or equal to the set value, it is determined that it is necessary to enter step S5 for fine-tuning design. When the proportion of the number of teeth that need fine-tuning to the total number of teeth is less than the set value, there is no need to enter step S5 for fine-tuning design, and the correction of the next correction stage can be carried out directly, that is, the shell-shaped orthodontic appliances of the next correction stage are worn in sequence.

[0105] In some other embodiments, after the step of calculating the offset between the actual tooth layout of the stage and the stage design target layout of the current correction stage, the following steps are also included:

[0106] When the offset exceeds a second preset threshold, the position of the next fine-tuning design point is modified to adjust the number of shell-shaped appliances in the shell-shaped dental instrument set corresponding to the next correction stage, wherein the second preset threshold is greater than the first preset threshold.

[0107] In this embodiment, the judgment of the offset and the second preset threshold can refer to the judgment between the aforementioned offset and the first preset threshold, which will not be repeated here. Since the second preset threshold is greater than the first preset threshold, when the offset between the actual tooth layout at the end of the current correction stage and the designed stage design target layout exceeds the second preset threshold, it means that the current correction stage may contain too many correction steps, and the accumulated offset formed by multiple correction steps is too large. In the current correction stage, there may be a situation where the appliance is uncomfortable to wear. The next correction stage should try to avoid this situation. Therefore, it is necessary to adjust the number of shell-shaped appliances in the next correction stage, such as modifying the position of the next fine-tuning design point to reduce the number of shell-shaped appliances in the next correction stage. At the same time, the positions of all subsequent fine-tuning design points of the next fine-tuning design point are adjusted accordingly. In some embodiments, the positions of all subsequent fine-tuning design points of the next fine-tuning design point can still be adjusted based on the unchanged number of shell-shaped appliances included in each correction stage, that is, the number of shell-shaped appliances included in the next correction stage is reduced only by moving the next fine-tuning design point, and other subsequent fine-tuning design points only change accordingly with the change of the position of the next fine-tuning design point, and the number of appliances included in each correction stage does not change; of course, the positions of all subsequent fine-tuning design points can also be adjusted based on the adjusted number of shell-shaped appliances in the next correction stage to adjust the number of appliances in the correction stages subsequent to the next correction stage, that is, when the next fine-tuning design point is moved to reduce the number of shell-shaped appliances included in the next correction stage, the number of appliances included in the subsequent correction stages is also reduced accordingly with the reduction in the number of appliances in the next correction stage.

[0108] In some embodiments, the second preset threshold value may be set to be greater than or equal to twice the first preset threshold value, that is, only when the offset value exceeds at least twice the first preset threshold value, the number of appliances in the next correction stage needs to be reduced. Specifically, when the offset value exceeds the second preset threshold value, the step of modifying the position of the next fine-tuning design point to reduce the number of shell-shaped appliances in the shell-shaped dental appliance set corresponding to the next correction stage further includes:

[0109] Calculating a difference between the offset and the corresponding first preset threshold;

[0110] determining a reduction in the number of shell-shaped appliances in the next shell-shaped dental appliance based on the difference and the first preset threshold;

[0111] The position of the next fine-tuning design point is adjusted according to the determined reduction in the number of shell-shaped appliances in the next shell-shaped dental appliance.

[0112] In some practical examples, assuming that the calculated offset between the actual tooth layout of the current tooth at the end of the current correction stage and the designed stage design target layout is T1, and the first preset threshold is Δ1, then the difference D1=T1-Δ1 between the offset and the corresponding first preset threshold is calculated, and then the ratio of the difference D1 to the first preset threshold Δ1 is calculated, and the reduction amount of the shell-shaped appliance in the next correction stage is determined according to the ratio. In this example, the reduction amount l of the shell-shaped appliance in the next correction stage is:

[0113]

[0114] For example, when calculating the obtained When it is 1.5, the number of shell-shaped appliances can be reduced by one in the next correction stage.

[0115] Of course, the number of shell-shaped appliances in the next correction stage cannot be reduced indefinitely. The result of the reduction should at least ensure that the number of shell-shaped appliances in the correction stage is greater than or equal to 5, and the difference in the number of shell-shaped appliances contained in adjacent shell-shaped dental instrument groups does not exceed 3.

[0116] Since the position of the next fine-tuning design point changes, the subsequent fine-tuning design points also need to be changed accordingly. In one example, the change of the subsequent fine-tuning design points does not change the number of shell-shaped appliances in the subsequent correction stages; and in another example, the number of shell-shaped appliances in the subsequent correction stages decreases accordingly with the reduction in the number of shell-shaped appliances in the next correction stage. The present invention is not limited to this.

[0117] Those skilled in the art will appreciate that the above embodiments are specific embodiments for implementing the present application, and in actual applications, various changes may be made thereto in form and detail without departing from the spirit and scope of the present application.

Claims

1. A dental correction system, characterized in that: include: A first type of dental appliance is designed to include N shell-shaped appliances for gradually repositioning a patient's teeth from a first tooth layout to a second tooth layout, the first type of dental appliance is divided into K shell-shaped dental appliance groups corresponding to K treatment stages, each shell-shaped dental appliance group includes two or more shell-shaped appliances, and the two or more shell-shaped appliances are used to gradually move the patient's teeth from a stage-designed initial layout of a current treatment stage to a stage-designed target layout, wherein N>2, K>=2; A fine-tuning dental appliance designed between adjacent correction stages, each fine-tuning dental appliance comprising M shell-shaped appliances, wherein the M shell-shaped appliances are designed to progressively position the patient's teeth from an actual tooth layout at the end of a previous correction stage to a stage design target layout of the previous correction stage, wherein M>=1.

2. The dental correction system according to claim 1, characterized in that: The elasticity of each shell-shaped appliance of the fine-tuning dental instrument is the same as the elasticity of each shell-shaped appliance of each shell-shaped dental instrument set.

3. The dental correction system according to claim 1, wherein: The elasticity of each shell-shaped appliance of the fine-tuning dental instrument is smaller than the elasticity of each shell-shaped dental appliance of the shell-shaped dental instrument set corresponding to the previous correction stage.

4. The dental correction system according to claim 3, characterized in that: The elasticity of each shell-shaped appliance of the fine-tuning dental apparatus gradually decreases with the wearing sequence.

5. The dental correction system according to any one of claims 1 to 4, characterized in that: The number M of shell-shaped appliances included in each fine-tuning dental instrument is: 1≤M≤5.

6. The dental correction system according to claim 5, characterized in that: The number M of shell-shaped appliances included in each fine-tuning dental instrument is: 1≤M≤3.

7. The dental correction system according to claim 5, characterized in that: Each shell-shaped dental instrument set contains 5 to 20 shell-shaped appliances.

8. The dental correction system according to claim 1, wherein: Each shell-shaped dental instrument set contains 8 to 15 shell-shaped appliances.

9. The dental correction system according to claim 5, characterized in that: Each shell-shaped dental instrument set comprises substantially the same number of shell-shaped appliances.

10. The dental correction system according to claim 5, characterized in that: The difference in the number of shell-shaped appliances included in adjacent shell-shaped dental instrument groups is less than or equal to 3.

11. A method for designing a dental correction system, characterized in that: The following steps are involved: Acquire a first digital model of the jaw and a second tooth layout, and form a series of target digital models of the jaw based on the first digital model of the jaw and the second tooth layout, wherein the series of target digital models of the jaw correspond to a series of orthodontic states of gradually advancing the patient's teeth from the first tooth layout to the second tooth layout; designing a first type of dental appliance based on the series of target dental and jaw digital models, the first type of dental appliance comprising N shell-shaped appliances for gradually repositioning the patient's teeth from the first tooth layout to the second tooth layout; Determine K-1 fine-tuning design points, wherein the K-1 fine-tuning design points divide the first type of dental appliances including the N shell-shaped appliances into K shell-shaped dental appliance groups corresponding to K correction stages, each shell-shaped dental appliance group includes two or more shell-shaped appliances, and the two or more shell-shaped appliances are used to gradually move the patient's teeth from the initial layout of the stage design of the current correction stage to the target layout of the stage design; Acquire a digital model of the actual dental jaw of the patient's teeth at the end of wearing each shell-shaped dental appliance set, wherein the digital model represents the actual dental layout of the patient at the end of the current correction stage; Based on the actual tooth-jaw digital model of the stage and the stage design target layout of the current correction stage, M fine-tuned tooth-jaw digital models are designed, and the M fine-tuned tooth-jaw digital models correspond to the tooth correction state of the patient's teeth gradually progressing from the actual tooth layout at the end of the current correction stage to the stage design target layout of the current correction stage; Fine-tuned dental appliances are designed based on the M fine-tuned dental jaw digital models, each of which includes M shell-shaped appliances, and the M shell-shaped appliances are designed to progressively position the patient's teeth from the actual tooth layout at the end of the current treatment stage to the target tooth layout designed in the stage.

12. The method for designing a dental correction system according to claim 11, wherein: Before the step of designing M fine-tuned tooth and jaw digital models based on the actual tooth and jaw digital model of the stage and the stage design target layout of the current correction stage, the step further includes: Acquire the actual tooth layout of the patient at the end of the current correction stage according to the actual dental digital model of the stage; Calculating the offset between the actual tooth layout of the stage and the stage design target layout of the current correction stage; When the offset exceeds a first preset threshold, M fine-tuned digital models of the jaws are generated according to the actual digital model of the jaws in the stage and the stage design target layout of the current correction stage.

13. The method for designing a dental correction system according to claim 12, wherein: After the step of calculating the offset between the actual tooth layout of the stage and the stage design target layout of the current correction stage, the method further includes: When the offset exceeds a second preset threshold, the position of the next fine-tuning design point is modified to adjust the number of shell-shaped appliances in the shell-shaped dental instrument set corresponding to the next correction stage, wherein the second preset threshold is greater than the first preset threshold.

14. The method for designing a dental correction system according to claim 13, wherein: The second preset threshold is at least greater than or equal to twice the first preset threshold.

15. The method for designing a dental correction system according to claim 13, wherein: When the offset exceeds the second preset threshold, the step of modifying the position of the next fine-tuning design point to adjust the number of shell-shaped appliances in the shell-shaped dental appliance set corresponding to the next correction stage includes: Calculating a difference between the offset and the first preset threshold; determining a reduction amount of the shell-shaped appliance in the next shell-shaped dental appliance set based on the difference and the first preset threshold; The position of the next fine-tuning design point is adjusted according to the determined reduction amount of the shell-shaped appliance in the next shell-shaped dental appliance set.

16. The method for designing a dental correction system according to claim 15, wherein: In the step of adjusting the position of the next fine-tuning design point according to the determined reduction amount of shell-shaped appliances in the next shell-shaped dental instrument group, the reduction of shell-shaped appliances in the next shell-shaped dental instrument group should satisfy that the difference in the number of shell-shaped appliances in the next shell-shaped dental instrument group and the shell-shaped appliances in the adjacent previous shell-shaped dental instrument group is less than or equal to 3, or the number of shell-shaped appliances in the next shell-shaped dental instrument group is greater than or equal to 5.

17. The method for designing a dental correction system according to any one of claims 12 to 16, characterized in that: When the offset exceeds the first preset threshold, M fine-tuned digital models of the jaws are generated according to the actual digital model of the jaws in the stage and the stage design target layout of the current correction stage, including: For each tooth or each determined characteristic tooth, determining in turn whether each offset component of the current tooth exceeds the corresponding first preset threshold, the offset between the actual tooth layout at the stage and the target layout designed at the stage includes the first to third offset components corresponding to the X-axis, Y-axis, and Z-axis offsets and the fourth offset component corresponding to the angle offset; When any offset component of a tooth exceeds a corresponding first preset threshold, it is determined that the current tooth needs to be fine-tuned; When any tooth needs to be fine-tuned, M fine-tuned tooth-jaw digital models are generated based on the actual tooth-jaw digital model at that stage and the target layout designed at that stage.

18. The method for designing a dental correction system according to any one of claims 12 to 16, characterized in that: When the offset exceeds the first preset threshold, M fine-tuned digital models of the jaws are generated according to the actual digital model of the jaws in the stage and the stage design target layout of the current correction stage, including: Determine several key offset components among the offset components of each tooth, wherein the offset between the actual tooth layout at the stage and the target layout designed at the stage includes first to third offset components corresponding to X-axis, Y-axis, and Z-axis offsets and a fourth offset component corresponding to an angle offset; Determining in turn for each tooth or each determined characteristic tooth whether each key offset component of the current tooth exceeds a corresponding first preset threshold; When any key offset component of a certain tooth exceeds the corresponding first preset threshold, it is determined that the current tooth needs to be fine-tuned; When any tooth needs to be fine-tuned, M fine-tuned tooth-jaw digital models are generated based on the actual tooth-jaw digital model at that stage and the target layout designed at that stage.

19. The method for designing a dental correction system according to any one of claims 12 to 16, characterized in that: When the offset exceeds the first preset threshold, M fine-tuned digital models of the jaws are generated according to the actual digital model of the jaws in the stage and the stage design target layout of the current correction stage, including: For each tooth or each determined characteristic tooth, normalizing each offset component of the current tooth in turn to obtain each normalized offset component, wherein the offset between the actual tooth layout at the stage and the target layout designed at the stage includes first to third offset components corresponding to the offsets of the X-axis, Y-axis, and Z-axis and a fourth offset component corresponding to the angle offset; Obtaining a comprehensive offset based on each normalized offset component; Determining whether the current tooth needs fine adjustment based on the comprehensive offset and the corresponding first preset threshold; When any tooth needs to be fine-tuned, M fine-tuned tooth-jaw digital models are generated based on the actual tooth-jaw digital model at that stage and the target layout designed at that stage.

20. The method for designing a dental correction system according to any one of claims 12 to 16, characterized in that: When the offset exceeds the first preset threshold, generating M fine-tuned tooth and jaw digital models according to the actual tooth and jaw digital model of the stage and the stage design target layout of the current correction stage, further comprising: Determining the teeth that need to be fine-tuned according to the offset of each tooth in the patient's dentition and the corresponding first preset threshold; Count the number of teeth in the patient's dentition that need fine-tuning; Whether fine-tuning is required is determined based on the statistically obtained ratio of the number of teeth that need fine-tuning to the total number of teeth in the patient's dentition.

Images