CN115252183A

CN115252183A - Multilayer orthodontic diaphragm with non-uniform thickness

Info

Publication number: CN115252183A
Application number: CN202210727853.XA
Authority: CN
Inventors: 殷朋举; 吕昱萱; 李路博; 廉希超
Original assignee: Hebei University of Engineering
Current assignee: Hebei University of Engineering
Priority date: 2022-06-24
Filing date: 2022-06-24
Publication date: 2022-11-01

Abstract

The invention provides a multi-layer orthodontic diaphragm with non-uniform thickness, and relates to the field of tooth orthodontics. The multilayer orthodontic diaphragm with the non-uniform thickness comprises a multilayer diaphragm formed by overlapping a plurality of single-layer diaphragms, wherein the thickness of the multilayer diaphragm is non-uniformly arranged, and the multilayer diaphragm is prepared by multilayer co-extrusion; according to the invention, the multilayer diaphragm is formed by co-extruding the plurality of single-layer diaphragms, so that the problems that the force applied by the existing orthodontic diaphragm cannot be sustained and stable, the teeth of a patient cannot be moved to an expected position, and a satisfactory orthodontic effect is difficult to obtain are solved; and through the inhomogeneous thickness of multilayer diaphragm, the thickness that has solved the orthodontic ware of current even thickness's stealthy orthodontic diaphragm preparation in incisor department is thinner than all the other local thickness, leads to the application of force of this department less, and along with correcting the time lapse, the actual removal and the design removal deviation of this department are bigger and bigger, seriously influence the correction efficiency of facing and the problem of wearing experience.

Description

Multilayer orthodontic diaphragm with non-uniform thickness

Technical Field

The invention relates to the technical field of tooth orthodontics, in particular to a multilayer orthodontic diaphragm with non-uniform thickness.

Background

The goal of orthodontics is to move a patient's teeth to a position that is optimal for function and/or aesthetics. Conventional aligners, such as brackets and the like, are created by a treating physician applying an archwire to a patient's teeth, with the archwire exerting a constant force on the patient and gradually urging them closer to the physician's desired position, with a series of shift adjustments ultimately moving the teeth to the desired position over the course of treatment time. However, the traditional correction uses the bracket and the arch wire, which affects the beauty, and the bracket is easy to remain food slag, the oral cavity is easy to breed bacteria, the bracket and the arch wire stimulate mucous membranes and soft tissues, and cause discomfort or inflammation of the soft tissues and dental caries.

The bracket-free invisible bracket is a technology for completing the whole correction treatment course by customizing a series of transparent denture bases through a 3D (three-dimensional) computer technology. Compared with the traditional orthodontic method, the bracket-free invisible correction can be freely taken off and worn, so the advantages of oral cleanness, comfort and aesthetic degree are obvious, but the bracket-free invisible correction needs high cooperation of patients (the daily wearing time needs more than 22 hours), if the bracket-free invisible correction cannot be worn according to the time requirement, the treatment course is prolonged to some extent, and the curative effect is greatly reduced. Therefore, the fixed orthodontic appliance has a certain gap in the aspects of treatment results, treatment indication application range and the like. The invention of the invisible correcting diaphragm promotes the development of the invisible correcting technology and can solve the clinical problem of the traditional orthodontic treatment. However, since the diaphragm used for manufacturing the invisible appliance is fast in attenuation of the orthodontic force generated in the oral cavity of a patient, and the duration time is short and cannot reach the lower limit of the orthodontic force threshold, the clinical moving effect is poor, the expected effect is not ideal, meanwhile, the treatment time is prolonged, and the compliance is poor due to the fact that the diaphragm used is high in hardness and the wearing comfort of the patient is not good enough, so that the final clinical treatment effect is further influenced. Therefore, the existing invisible appliance cannot continuously and stably move the teeth of the patient to the expected position due to the force applied by the orthodontic diaphragm used in the orthodontic process, and is difficult to obtain a satisfactory orthodontic effect.

The orthodontic diaphragm is also called as orthodontic diaphragm, dental diaphragm and the like, and is mainly used for manufacturing orthodontic braces. Because of the inherent characteristics of the tooth shape and the diaphragm material thermal forming, the thickness of the incisor in the appliance made of the invisible orthodontic diaphragm with uniform thickness is thinner than the thicknesses of other places, so that the force application at the position is smaller, the actual movement and the design movement deviation at the position are larger and larger along with the lapse of the correction time, and the correction efficiency and the wearing experience of the tooth socket are seriously influenced, therefore, the force application at the incisor in the appliance made of the invisible orthodontic diaphragm with uniform thickness cannot become one of the pain points in the industry.

Disclosure of Invention

The invention aims to provide a multilayer orthodontic diaphragm with non-uniform thickness, which can solve the problems that the force applied by the existing orthodontic diaphragm cannot be continuous and stable, the teeth of a patient cannot be moved to an expected position, and a satisfactory orthodontic effect is difficult to obtain, and the problems that the force applied to the position is smaller, the actual movement and the design movement deviation of the position are larger and larger along with the lapse of correction time, and the correction efficiency and the wearing experience of a tooth socket are seriously influenced because the thickness of the incisor in an appliance made of the existing invisible orthodontic diaphragm with uniform thickness is thinner than the thickness of the rest positions.

The embodiment of the invention is realized by the following steps:

the embodiment of this application provides an orthodontic diaphragm of inhomogeneous thickness of multilayer, it includes the multilayer diaphragm that a plurality of individual layer diaphragm stack are constituteed, the inhomogeneous setting of thickness of multilayer diaphragm, the multilayer diaphragm is formed through the preparation of multilayer coextrusion.

When the orthodontic film is used, the cost of polymer materials can be reduced by the multi-layer film through the composite film formed by co-extrusion, and meanwhile, the strength and the crack resistance of the orthodontic film are improved by different polymer materials; the thickness of incisor department can keep unanimous with the thickness in other places when ware is rescued in its preparation to the just abnormal diaphragm of inhomogeneous setting, and the force application effect that realizes the different positions of rescuring the ware is the same, has reduced and has corrected the deviation for correct effectually.

According to the invention, the multilayer diaphragm is formed by co-extruding the plurality of single-layer diaphragms, so that the problems that the force applied by the existing orthodontic diaphragm cannot be sustained and stable, the teeth of a patient cannot be moved to an expected position, and a satisfactory orthodontic effect is difficult to obtain are solved; and through the inhomogeneous thickness of multilayer diaphragm, the thickness that has solved the orthodontic ware of current even thickness's stealthy orthodontic diaphragm preparation in incisor department is thinner than all the other local thickness, leads to the application of force of this department less, and along with correcting the time lapse, the actual removal and the design removal deviation of this department are bigger and bigger, seriously influence the correction efficiency of facing and the problem of wearing experience.

In some embodiments of the present invention, the number of layers of the single-layer film sheet is at least two. The number of single-layer membranes of the multi-layer membrane is generally between 3 and 7, and the more the number of layers, the better the performance of the multi-layer membrane.

In some embodiments of the present invention, the thickness of each of the single-layer films is different. The single-layer membrane is made of different materials and has different physical properties, and the different thicknesses are beneficial to the development of the physical properties.

In some embodiments of the present invention, the thickness of the single-layer membrane gradually decreases from the periphery to the middle. The thickness of the edge of the single-layer diaphragm is thicker, the middle of the single-layer diaphragm is thinner, when the single-layer diaphragm is manufactured into an appliance, the thickness of orthodontic diaphragms on two sides of an incisor is larger, the intensity of force application is ensured, and the thickness of the top of the incisor is smaller, so that a patient can feel more comfortable when wearing the appliance; and the application of force that the department of grinding one's teeth in the department can lead to this department because the tooth face is wider, and the just abnormal diaphragm position that the grinding one's teeth in the mouth corresponds generally is in both sides, consequently increases just abnormal diaphragm's thickness all around, and middle thickness reduces, can increase the correction efficiency and the wearing experience of facing.

In some embodiments of the invention, the stiffness of adjacent single-layer membranes is different. The single-layer diaphragms with different hardness are co-extruded to form the multi-layer diaphragms, the durability and the wear resistance of the appliance can be improved due to the specific physical properties of the multi-layer diaphragms, the failure caused by excessive wear in the inserting and pulling-out processes is prevented, and certain resilience and form retention force are ensured.

In some embodiments of the present invention, the stiffness of the single-layer membrane sheet increases from the outer side to the inner side of the multi-layer membrane sheet. The single-layer diaphragm hardness that is close to in the middle of the multilayer diaphragm is big, and the single-layer diaphragm hardness of multilayer diaphragm both sides is little, and such hardness overall arrangement can be like the relation of skeleton and blood meat, and this kind of structural design makes just abnormal diaphragm produce more continuously to stabilize effectively and correct the power.

In some embodiments of the present invention, the adjacent one of the single-layer membrane pieces having low hardness has high hardness, and the adjacent one of the single-layer membrane pieces having high hardness has low hardness. The single-layer diaphragm that hardness is low superposes with the single-layer diaphragm that hardness is high in turn, and this kind of structural design can also make when increasing the persistence and the wearability of correcting the ware and guarantee certain resilience and form retentivity, has increased the intensity and the crack resistance of just abnormal diaphragm.

In some embodiments of the present invention, the stiffness of the single-layer membrane is low on both sides of the edge of the multi-layer membrane. After the two sides of the edge of the multilayer film are made into the orthodontic appliance, the gum part of a patient can be contacted when the patient wears the orthodontic appliance, and the edge with low hardness can increase the wearing experience of the tooth socket.

In some embodiments of the present invention, the thickness of the single-layer membrane corresponds to the hardness of the single-layer membrane. The single-layer diaphragm with high hardness is large in thickness, and the durability and the wear resistance of the appliance made of the orthodontic diaphragm can be guaranteed.

In some embodiments of the present invention, the thickness of the single-layer membrane sheet is not more than 0.5mm. The invisible bracket-free orthodontic appliance is a movable orthodontic device made of transparent elastic materials and designed and manufactured by computer assistance, and consists of a series of orthodontic appliances, and the aim of straightening teeth is finally achieved through continuous small-range movement of the teeth. The membrane material commonly used by the appliance in the prior art has uniform thickness which is between 0.6 and 0.8 mm. In the invention, as the orthodontic membranes are of non-uniform thickness, each single-layer membrane is also of non-uniform thickness, and the thickness of the thickest part of the single-layer membrane is not more than 0.5mm; the thickest part of the orthodontic diaphragm is not more than 1.2mm.

Compared with the prior art, the embodiment of the invention has at least the following advantages or beneficial effects:

(1) According to the orthodontic diaphragm, the multilayer diaphragm is formed by co-extruding the plurality of single-layer diaphragms, the cost of polymer materials can be reduced by the aid of the composite diaphragm formed by co-extruding the plurality of single-layer diaphragms, and meanwhile, the strength and the crack resistance of the orthodontic diaphragm are improved by different polymer materials, so that the problems that force applied by the existing orthodontic diaphragm cannot be sustained and stable, teeth of a patient cannot be moved to an expected position, and a satisfactory orthodontic effect is difficult to obtain are solved.

(2) According to the invention, through the non-uniform thickness of the multi-layer diaphragm, the thickness of the incisor part can be kept consistent with the thickness of other parts when the appliance is manufactured, the same force application effect of different parts of the appliance is realized, the correction deviation is reduced, the correction effect is good, and the problems that the thickness of the incisor part in the existing appliance manufactured by the invisible orthodontic diaphragm with uniform thickness is thinner than the thickness of other parts, so that the force application of the incisor part is smaller, and the actual movement and the design movement deviation of the incisor part are larger and larger along with the lapse of correction time, so that the correction efficiency and the wearing experience of the braces are seriously influenced are solved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

Fig. 1 is a schematic cross-sectional view of an orthodontic film with a thick side edge and a thin middle portion;

FIG. 2 is a schematic cross-sectional view of an orthodontic film with thick side edges and a thin middle portion;

FIG. 3 is a schematic cross-sectional view of another orthodontic film with thick side edges and thin middle;

fig. 4 is a schematic view of another orthodontic film with thick side edges and thin middle.

An icon: 1. a multilayer membrane; 2. a single layer membrane.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the embodiments of the present invention, it should be noted that, if the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate an orientation or a positional relationship based on an orientation or a positional relationship shown in the drawings, or an orientation or a positional relationship which is usually arranged when the product of the present invention is used, it is only for convenience of description and simplification of the description, but does not indicate or imply that the device or the element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

Furthermore, the terms "horizontal", "vertical", "overhang" and the like do not require that the components be absolutely horizontal or overhang, but may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the embodiments of the present invention, "a plurality" means at least 2.

In the description of the embodiments of the present invention, it should be further noted that unless otherwise explicitly stated or limited, the terms "disposed," "mounted," "connected," and "connected" should be interpreted broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood according to specific situations by those of ordinary skill in the art.

Example 1

The embodiment provides a multilayer orthodontic diaphragm with non-uniform thickness, as shown in fig. 1, the multilayer orthodontic diaphragm comprises a multilayer diaphragm 1 formed by overlapping a plurality of single-layer diaphragms 2, the thickness of the multilayer diaphragm 1 is non-uniform, and the multilayer diaphragm 1 is prepared by multilayer co-extrusion.

When the orthodontic film is used, the cost of polymer materials can be reduced by the aid of the composite film formed by the multilayer film 1 through co-extrusion, and meanwhile, the strength and the crack resistance of the orthodontic film are improved by different polymer materials; the thickness of incisor department can keep unanimous with the thickness in other places when ware is rescued in its preparation to the just abnormal diaphragm of inhomogeneous setting, and the force application effect that realizes the different positions of rescuring the ware is the same, has reduced and has corrected the deviation for correct effectually.

The composite co-extruded sheet material enables multiple layers of materials with different characteristics to be compounded with each other in the extrusion process, so that the product has the excellent characteristics of a plurality of different materials, and the characteristics are complemented, thereby obtaining special required performances and appearances, such as oxygen-proof and moisture-proof barrier capability, colorability, heat preservation, thermoforming and thermal bonding capability, strength, rigidity, hardness and other mechanical properties 26859.

According to the invention, the multilayer diaphragm 1 is formed by co-extruding the plurality of single-layer diaphragms 2, so that the problems that the force applied by the existing orthodontic diaphragm cannot be sustained and stable, the teeth of a patient cannot be moved to an expected position, and a satisfactory orthodontic effect is difficult to obtain are solved; and through the inhomogeneous thickness of multilayer diaphragm 1, solved the thickness of incisor department than all the other places thickness in the ware is rescued to stealthy orthodontic diaphragm preparation of current even thickness, lead to the application of force of this department less, along with correcting the time lapse, the actual removal and the design of this department remove the deviation bigger and bigger, seriously influence the correction efficiency of facing and the problem of wearing experience.

The hot pressing film material used in orthodontics is a kind of polymer with different characteristics, mainly including polyethylene terephthalate (PET), polyethylene terephthalate-polyethylene glycol (PETG), thermoplastic Polyurethane (TPU), polycarbonate (PC), polypropylene (PP) material and Ethylene Vinyl Acetate (EVA).

PET has strain-mediated crystallization properties that increase the density of the material, increase its resistance to gas permeation, and thus achieve long-term dimensional stability, while allowing anisotropy in the final product. The importance of anisotropy is that the stiffness of the product can be increased in a particular direction. PET is a widely used hot-press film material due to its superior fatigue resistance and dimensional stability.

PETG is glycol-modified PET. It is a noncrystalline amorphous polymer with good mechanical, optical, fatigue and dimensional stability, and good fluidity and solubility.

TPU is a thermoplastic material commonly used in bracket-free invisible orthodontic appliances, has high elasticity and is considered to meet the requirements of light and continuous orthodontic force in the orthodontic process. TPUs have both the mechanical properties of vulcanizates and the processability of thermoplastic polymers. Since there is no chemical network structure in general rubber, it can be melted and processed repeatedly. TPU has a variety of excellent properties including high tensile strength, high tear strength, high abrasion resistance, oil and solvent resistance, low temperature flexibility, and the like. However, the increase of TPU in the material can lead to the decrease of the transparency of the product, and the final aesthetic property is influenced.

The PC can be combined with other polymers to be used for manufacturing the hot-pressing film diaphragm for orthodontics, for example, the Durasoft diaphragm is formed by combining the PC and the TPU, and can release relatively constant orthodontic force. PC has high strength, high dimensional stability, high durability, and low water absorption rate. The viscosity of the melted PC makes it show good impact strength and toughness. It has similar properties to polymethylmethacrylate, but PC is stronger and can be used over a larger temperature range. Meanwhile, PC has light transmittance superior to that of many glass materials, so that the product has excellent aesthetic property.

PP is an important and commonly used polymer. It has excellent mechanical performance, insulating performance, heat stability, chemical stability and biocompatibility. But its dimensional stability is poor, its thermoformability is limited, and its brittleness also limits its applications in some areas.

EVA is a thermoplastic polymer synthesized from ethylene and Vinyl Acetate (VA) that has good biocompatibility, is resistant to dissolution, and is non-toxic, and can be used to make transparent pressed film holders. The different content of VA in EVA can change its performance. At high VA levels, the polarity, adhesion, impact resistance, elasticity and compatibility of EVA increase, but at the same time the crystallinity, stiffness, softening temperature and melting point decrease.

The material with higher hardness adopts PETG, TPU, PC and the like, and the material with lower hardness adopts TPU, TPE, EVA, TPV and the like. The material with lower hardness has the hardness of 60A-85D, the tensile strength of more than 34MPa, the elongation of more than 200 percent, the flexural modulus of more than 240MPa, the elongation at break of more than 40 percent after 24 hours at the compression temperature of 70 ℃, and the light transmittance of 400-800nm of more than 75 percent; the yield elongation of the material with higher hardness is more than 4 percent, the flexural modulus is more than 600MPa, the stress relaxation degree in 24 hours is more than 10 percent under the humid environment with the relative humidity of 90 to 100 percent, and the light transmittance at 400 to 800nm is more than 75 percent.

Example 2

This example provides a multi-layer orthodontic film with non-uniform thickness, as shown in fig. 2, which is substantially the same as example 1, and the main difference is that: the number of layers of the single-layer membrane 2 is at least two. The number of the single-layer membrane 2 of the multi-layer membrane 1 is generally between 3 and 7, and the larger the number of the layers, the better the performance of the multi-layer membrane 1.

The three-layer structure can be that the inner layer is a reinforced resin core, the middle layer is a TPU soft polymer, and the outer layer is a PETG hard polymer. The resin core added on the surface and the cut end improves the wear resistance and the mechanical strength of the material, can prevent the buccal-palatal side deformation of the retainer, the TPU layer has a buffer function, and the PETG layer has good formability, optical performance, fatigue resistance and dimensional stability, and is beneficial to maintaining the bow shape.

Further, the thickness of each single-layer membrane sheet 2 is different. The single-layer membrane 2 is made of different materials and has different physical properties, and the different thicknesses are beneficial to the development of the physical properties.

Further, the thickness of the single-layer membrane sheet 2 gradually decreases from the periphery to the center. The thickness of the edge of the single-layer diaphragm 2 is thicker, the middle of the single-layer diaphragm is thinner, when the single-layer diaphragm is manufactured into an appliance, the thickness of orthodontic diaphragms on two sides of an incisor is larger, the intensity of force application is ensured, and the thickness of the top of the incisor is smaller, so that a patient can feel more comfortable when wearing the appliance; and molar department because the tooth face broad, less thickness can lead to the application of force of this department less, and the just abnormal diaphragm position that the molar corresponds generally is in both sides, consequently with just abnormal diaphragm's thickness increase all around, middle thickness reduces, can increase the correction efficiency and the experience of wearing of facing.

Example 3

This embodiment provides a multi-layer orthodontic film with non-uniform thickness, as shown in fig. 3, which is substantially the same as

embodiment

1 or 2, and the main difference between them is that: the hardness of the adjacent single-layer membranes 2 is different. The multilayer diaphragm 1 formed by co-extruding the single-layer diaphragms 2 with different hardness has specific physical properties, so that the durability and the wear resistance of the appliance can be improved, the failure caused by excessive wear in the inserting and pulling processes is prevented, and certain resilience and form retention force are ensured.

Further, the single-layered diaphragms 2 have hardness increasing sequentially from the single-layered diaphragms 2 located at both sides of the multi-layered diaphragm 1 to the single-layered diaphragm 2 located in the middle of the multi-layered diaphragm 1, respectively. The single-layer diaphragm 2 hardness that is close to in the middle of the multilayer diaphragm 1 is big, and the single-layer diaphragm 2 hardness of multilayer diaphragm 1 both sides is little, and such hardness overall arrangement can be like the relation of skeleton and blood meat, and this kind of structural design makes just abnormal diaphragm produce more continuously stable effective power of correcting.

Further, the adjacent single-layer membrane pieces 2 of the single-layer membrane piece 2 having low hardness are high in hardness, and the adjacent single-layer membrane pieces 2 of the single-layer membrane piece 2 having high hardness are low in hardness. The single-layer diaphragm 2 that hardness is low superposes with the single-layer diaphragm 2 that hardness is high in turn, and this kind of structural design can also make when increasing the persistence and the wearability of correcting the ware and guarantee certain resilience and form retentivity, has increased the intensity and the crack resistance of just abnormal diaphragm.

Further, the single-layered sheet 2 located on both sides of the edge of the multi-layered sheet 1 has a low hardness. After the two sides of the edge of the multilayer film 1 are made into the orthodontic devices, the gingival part of a patient can be contacted when the patient wears the orthodontic devices, and the edge with low hardness can increase the wearing experience of the tooth socket.

Example 4

This example provides a multilayer, non-uniform thickness orthodontic film, as shown in fig. 3, which is substantially the same as any one of examples 1-3, and the main differences are as follows: the higher the stiffness of the single-layer membrane 2, the greater its thickness. The single-layer diaphragm 2 with high hardness has large thickness, and can ensure the durability and the wear resistance of the appliance made of the orthodontic diaphragm.

Further, the thickness of the single-layer membrane sheet 2 is not more than 0.5mm. The invisible bracket-free orthodontic appliance is a movable orthodontic device made of transparent elastic materials and designed and manufactured by computer assistance, and consists of a series of orthodontic appliances, and the aim of straightening teeth is finally achieved through continuous small-range movement of the teeth. The membrane material commonly used by the appliance in the prior art has uniform thickness which is between 0.6 and 0.8 mm. In the invention, as the orthodontic diaphragm has non-uniform thickness, each single-layer diaphragm 2 also has non-uniform thickness, and the thickness of the thickest part of the single-layer diaphragm 2 is not more than 0.5mm; the thickest part of the orthodontic diaphragm is not more than 1.2mm.

In summary, the embodiments of the present invention provide a multi-layer orthodontic film with non-uniform thickness, which has at least the following advantages or benefits:

(1) According to the orthodontic diaphragm, the multilayer diaphragm 1 is formed by co-extruding the single-layer diaphragms 2, the cost of polymer materials can be reduced by the aid of the composite diaphragm formed by co-extruding the multilayer diaphragm 1, meanwhile, the strength and the crack resistance of the orthodontic diaphragm are improved by different polymer materials, and the problems that force applied by the existing orthodontic diaphragm cannot be sustained and stable, teeth of a patient cannot be moved to an expected position, and a satisfactory orthodontic effect is difficult to obtain are solved.

(2) According to the invention, through the non-uniform thickness of the multilayer diaphragm 1, the thickness of the incisor part and the thickness of other parts can be kept consistent when the appliance is manufactured, the same force application effect of different parts of the appliance is realized, the correction deviation is reduced, the correction effect is good, and the problems that the force application of the incisor part is smaller, the actual movement and the design movement deviation of the incisor part are larger and larger along with the lapse of correction time, and the correction efficiency and the wearing experience of the braces are seriously influenced because the thickness of the incisor part is thinner than the thickness of other parts in the appliance manufactured by the existing invisible orthodontic diaphragm with uniform thickness are solved.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The multilayer orthodontic diaphragm with the non-uniform thickness is characterized by comprising a multilayer diaphragm formed by overlapping a plurality of single-layer diaphragms, wherein the thickness of the multilayer diaphragm is non-uniformly arranged, and the multilayer diaphragm is prepared by multilayer co-extrusion.

2. The multi-layer orthodontic film with non-uniform thickness as claimed in claim 1, wherein the number of the single-layer film is at least two.

3. The multi-layer orthodontic film with non-uniform thickness as claimed in claim 2, wherein the thickness of each single-layer film is different.

4. The multi-layered orthodontic film with non-uniform thickness as claimed in claim 3, wherein the thickness of the single-layered film is gradually decreased from the periphery to the middle.

5. The multi-layer orthodontic film with non-uniform thickness as claimed in any one of claims 1 to 4, wherein the hardness of adjacent single-layer film is different.

6. The multi-layered orthodontic film with non-uniform thickness as claimed in claim 5, wherein the hardness of the single-layered film increases from the outer side to the inner side of the multi-layered film.

7. The multi-layer orthodontic film with non-uniform thickness as claimed in claim 5, wherein the adjacent single-layer film of the single-layer film with low hardness has high hardness, and the adjacent single-layer film of the single-layer film with high hardness has low hardness.

8. The multi-layer orthodontic film with non-uniform thickness as claimed in claim 7, wherein the single-layer film on both sides of the edge of the multi-layer film has low hardness.

9. The multi-layered orthodontic film with non-uniform thickness as claimed in any one of claims 6 to 8, wherein the thickness of the single-layered film corresponds to the hardness of the single-layered film.

10. The multi-layer orthodontic film with non-uniform thickness as claimed in claim 9, wherein the thickness of the single-layer film is not more than 0.5mm.