CN115770114B

CN115770114B - Three-way traction hook for tooth correction

Info

Publication number: CN115770114B
Application number: CN202211493370.4A
Authority: CN
Inventors: 徐晖; 邢璐; 白丁
Original assignee: Sichuan University
Current assignee: Sichuan University
Priority date: 2022-11-25
Filing date: 2022-11-25
Publication date: 2024-03-08
Anticipated expiration: 2042-11-25
Also published as: CN115770114A

Abstract

The invention provides a three-way traction hook for tooth correction, which comprises a base piece, a two-way traction hook piece and a one-way traction hook piece which are fixedly connected with each other; the bidirectional traction hook piece is formed by fixing a pair of traction hooks with opposite traction directions and a bidirectional traction hook connector; the unidirectional traction hook piece is formed by fixing a single traction hook and a unidirectional traction hook connector; in the direction perpendicular to the tooth bonding surface, the smaller included angle of the two included angles formed by the traction hooks in the unidirectional traction hook piece and the traction hooks in the bidirectional traction hook piece is 20-80 degrees. The three-way traction hook can be used for efficiently controlling root movement or controlling root movement of inclined teeth and simultaneously integrally moving, so that the purpose of correcting the teeth which are efficiently and vertically inclined is realized, the orthodontic treatment time is greatly shortened, side effects in the vertical tooth process can be prevented, the correction safety is improved, and the correction efficiency is improved.

Description

Three-way traction hook for tooth correction

Technical Field

The invention relates to the technical field of orthodontic appliances in stomatology, in particular to a three-way traction hook for tooth correction.

Background

In the tooth correction process, particularly in the process of closing the tooth extraction gap in the tooth extraction case, the phenomenon that teeth on two sides of the gap are inclined to the tooth extraction gap often occurs. In addition, in traditional fixed correction and invisible correction, root control movement and overall movement of teeth are all movement types which are difficult to realize clinically.

In clinical operation, if the situation of inclination of teeth at the gap side occurs in the process of closing the tooth extraction gap, various curves are bent on an arch wire to realize root control movement to vertically incline teeth in fixed correction, and the method needs longer treatment period, is complex in arch wire bending and needs long operation time for waiting for a patient on site; in the invisible correction, the teeth are vertically arranged in a mode of combining resin accessory design or tooth socket stress and elastic traction, the method also needs longer treatment period, the requirement on compliance of patients is very high, and the correction failure can be caused by slightly non-fitting tooth socket. Summarizing, in both fixed correction and invisible correction, the prior art has the defects of low efficiency, insufficient efficiency, high manual operation fineness requirement for doctors or patients and the like when vertically moving inclined teeth.

To solve the above-described problem, it is necessary to design a force application device that applies forces in a plurality of directions to the same action site. Through retrieving, there is the researcher and puts forward a device similar to two-way traction hook, for example chinese patent application "a novel traction hook device for orthodontic use" (CN 215606411U) discloses a novel traction hook device for orthodontic use, including route line, base, first traction strip, second traction strip, third traction strip and fourth traction strip, the route line rear end bonds there is the base, route line is close to rear end department and bonds there is first traction piece, route line left end bonds there is the second traction piece, route line is close to right-hand member department and bonds there is the third traction piece, first traction strip both ends second traction strip both ends all are equipped with from the latch hook, third traction strip both ends fourth traction strip both ends all are equipped with from the latch hook, first traction piece outer wall a week evenly is equipped with a link, second traction piece outer wall a week evenly is equipped with the second link, third traction piece outer wall a week evenly is equipped with three links, has promoted traction hook and tooth installation time and convenient and fast when the position was adjusted to the convenience when having improved traction hook and tooth installation.

However, the technical scheme disclosed in the prior art generally has the problem of single force application mode, so that the actual force application mode to teeth is not different from the traditional traction mode, and the high-efficiency correction of root control movement or root control simultaneous integral movement to severely inclined teeth cannot be realized.

Disclosure of Invention

In view of the above-mentioned drawbacks of the prior art, an object of the present invention is to provide a three-way traction hook for orthodontic treatment, which can be used for performing efficient root control movement or root control simultaneous overall movement on inclined teeth, so as to achieve the purpose of correcting the highly efficient vertical inclined teeth, thereby greatly shortening orthodontic treatment time, preventing side effects in the vertical teeth process, improving orthodontic safety, and improving orthodontic efficacy.

In order to achieve the above object, the present invention is realized by adopting the technical scheme comprising the following technical measures.

A three-way traction hook for tooth correction comprises a base piece, a two-way traction hook piece and a one-way traction hook piece which are fixedly connected with each other;

the bidirectional traction hook piece is formed by fixing a pair of traction hooks with opposite traction directions and a bidirectional traction hook connector;

the unidirectional traction hook piece is formed by fixing a single traction hook and a unidirectional traction hook connector;

The base piece comprises a connecting seat head and an adhesive pedestal used for being adhered to the adhesive surface of the teeth, and the base piece, the bidirectional traction hook piece and the unidirectional traction hook piece are fixedly connected with each other through the fixed connection between the connecting seat head and the bidirectional traction hook connecting body and the unidirectional traction hook connecting body;

in the direction perpendicular to the tooth bonding surface, the smaller included angle of the two included angles formed by the traction hooks in the unidirectional traction hook piece and the traction hooks in the bidirectional traction hook piece is 20-80 degrees.

Herein, the pulling hook of the unidirectional pulling hook member and the pair of pulling hooks of the bidirectional pulling hook member are pulling hooks conventionally used in the field of orthodontic technology, and mainly comprise a hook body and a rod body. It should be noted that, in this context, the towing hook is a component thereof, which is a conventional medical device in the art for achieving the towing purpose, and may be a specific solution given in this context, or may be a structure that refers to other disclosed towing hooks in the art or serves the same towing purpose.

In one of the technical schemes, the traction hook mainly comprises a hook body and a rod body. Wherein, the one end of the rod body is connected with the hook body, and the other end is connected with the two-way traction hook connector/the one-way traction hook connector.

Further, the structure of the hook body may be a curved configuration with a tip and an open structure, such as a question mark hook; an annular configuration without a tip, such as a circular ring hook, is also possible.

Further, the rod body may have a straight rod configuration or a non-straight rod configuration. However, it should be noted that when the rod body is in a non-straight rod configuration, the force and the force applied to the two ends of the rod body should be ensured to be consistent with those of the rod body in the straight rod configuration, so as to achieve the same technical effect.

Further, the sizes and materials of the hook body and the rod body can be traction hooks which are conventionally used in the technical field of reference dentistry orthodontic, and the following technical scheme can also be adopted:

in one preferred technical scheme, the hook body and the rod body are made of metal materials, including but not limited to stainless steel materials (it is to be noted that stainless steel is currently commonly used as an appliance material in the technical field of orthodontic appliances for dentistry, and specific stainless steel types can refer to the selection of appliances in the same field); the length of the rod body is 1-8 mm, and the outer diameter of the hook body is not more than 6mm, so that the hook body is suitable for being placed in the oral cavity of a human body as much as possible.

In this context, the base member comprises a connecting head and an adhesive abutment for adhering to the tooth adhesive surface, wherein the adhesive abutment is adapted to adhere to the tooth adhesive surface to secure the three-way pulling hook provided in the present technology in the mouth of a person. For the above functional purposes, the bonding stand described herein may refer to other bonding stands disclosed in the art or structures playing the same role of bonding fixation, and the following technical solutions may also be adopted:

in one embodiment, the bonding pad comprises a cylindrical shape or a polygonal shape, preferably a cylindrical shape.

In one preferred embodiment, in order to enhance the bonding effect, the bonding surface of the bonding base is a non-smooth plane, for example, a grind is provided to enhance the bonding effect of the adhesive.

In one preferable technical scheme, the outer diameter of the bonding pedestal is 2-6 mm, and the thickness is 0.3-1.5 mm.

The base member comprises a connecting seat head and an adhesive pedestal for adhering to the tooth adhesive surface, and the base member, the bidirectional traction hook member and the unidirectional traction hook member are fixedly connected with each other through the fixed connection between the connecting seat head and the bidirectional traction hook connector and the unidirectional traction hook connector, wherein the fixed connection between the connecting seat head and the bidirectional traction hook connector and the unidirectional traction hook connector can be directly and fixedly connected with the bidirectional traction hook connector and the unidirectional traction hook connector through, for example, adhesion or threaded connection; the connecting seat head and the bidirectional traction hook connector and the unidirectional traction hook connector can be connected and fixed through other fixing functional components, such as screws.

In one technical scheme, the connecting seat head, the bidirectional traction hook connector and the unidirectional traction hook connector are in a circular cylinder shape with internal threads, have the same inner diameter and are fixedly connected in series through screws. Further preferably, the outer diameters of the connecting seat head, the bidirectional traction hook connector and the unidirectional traction hook connector are consistent, and the connecting seat head, the bidirectional traction hook connector and the unidirectional traction hook connector are fixedly connected in series through screws to form a cylinder shape.

In one of the technical schemes, the connecting seat head, the bidirectional traction hook connector and the unidirectional traction hook connector are provided with annular bulges at the fixed connection positions of the connecting seat head, the bidirectional traction hook connector and the unidirectional traction hook connector, so that the embedded fixing function is achieved, the stability of the fixed connection is further improved, and the bidirectional traction hook piece and the unidirectional traction hook piece are prevented from rotating relatively under the fixed state. Further, a grind may be provided on the annular protrusion to further prevent the occurrence of relative rotation.

In one preferable technical scheme, the outer diameter of the connecting seat head, the bidirectional traction hook connector and the unidirectional traction hook connector is 0.5-3 mm, and the height is 1-6 mm, so that the connecting seat head, the bidirectional traction hook connector and the unidirectional traction hook connector are suitable for being placed in the oral cavity of a human body as much as possible.

It is important to note that in the above technical solution of the present invention, in order to achieve the purpose of three-way traction, the two-way traction hook and the one-way traction hook are selected and limited to be distinguished, so that on one hand, the industrial cost is reduced, and on the other hand, the angle between the two-way traction hook and the one-way traction hook is more important, and the angle can be adjusted for repeated use.

The invention is characterized in that the ratio of the couple applied on the teeth to the traction force passing through the tooth resistance center is controlled by arranging the included angle between the bidirectional traction hook piece and the unidirectional traction hook piece, so that the root control movement or the root control simultaneous integral movement can be designed for the teeth with different degrees of dislocation; and the magnitude of the couple applied to the tooth is controlled by the angle setting, thereby producing efficient tooth movement. Meanwhile, the corrected teeth can be bonded in a personalized way according to actual clinical requirements so as to achieve the corresponding clinical purposes.

In order to better explain the invention and the principle, the following correction method of the three-way traction hook is provided to assist in description:

a method for correcting a three-way traction hook for correcting teeth mainly comprises the following steps:

the three-way traction hook is adhered to the tooth bonding surface of the tooth to be traction, based on the view angle in the direction vertical to the tooth bonding surface,

so that the traction hook of the unidirectional traction hook piece and the dentition of the traction tooth are positionedThe plane is vertical and the plane is vertical,

or the included angle between the long axis of the traction hook of the unidirectional traction hook piece and the long axis of the tooth body of the tooth to be pulled is 0-45 degrees;

the traction hooks in the unidirectional traction hook piece and the pair of traction hooks in the bidirectional traction hook piece form an included angle respectively in the near middle direction and the far middle direction, wherein the smaller included angle is 20-80 degrees.

In general, and when the vestibular sulcus of the pulled tooth is clinically judged to have a deeper feature, or when the pulled tooth is clinically required to be straightened and simultaneously performs a mesial or distal overall movement or a root control movement, the pulling hook of the unidirectional pulling hook member and the dentition where the pulled tooth is located are preferably made to beThe plane is vertical. Clinically, the teeth are pulled and +.>The angle of the plane continuously changes, so that if the traction hook of the unidirectional traction hook piece is parallel to the tooth long axis of the tooth to be traction, the rootA number of variables (tooth inclination, pair of hooks in bi-directional hook element and +.>Plane angle, traction direction) calculation and continuous adjustment, thereby greatly increasing the setting and use difficulty of the three-way traction hook. However, if the technical scheme that the included angle between the long axis of the traction hook of the unidirectional traction hook piece and the long axis of the tooth body of the towed tooth is 0-45 degrees is adopted, the hook body of the unidirectional traction hook can be positioned at a larger distance from the gingival of the center of tooth resistance to generate larger root control moment, and the root control movement of the towed tooth is facilitated, so that the tooth straightening effect is better.

In the above technical solution, based on the view angle in the direction perpendicular to the tooth bonding surface, after determining the orientation of the traction hook of the unidirectional traction hook, the traction hook in the unidirectional traction hook and the pair of traction hooks in the bidirectional traction hook form a smaller one of two angles, which is a fixed value selected in advance within the range of 20-80 °. Thus in the above technical solution, a pair of towing hook orientations in the bidirectional towing hook exist andin the case where the planes are parallel, if intra-jaw traction is generated, a couple cannot be formed, and therefore, a mode of performing inter-jaw traction may be selected to apply the couple.

The couple is formed by adding a pair of forces with equal magnitude and opposite directions on the bidirectional traction hook piece, so that the inclined teeth can rotate around the center of resistance, and the effect of vertically inclining the teeth is achieved; at the same time, can apply a force parallel to the unidirectional traction hookForce in the plane direction causes the teeth to move integrally due to the fact that the force application points are close to the resistance centers of the teeth; the couple and the force can be controlled by controlling the length of the rod body of the traction hook and the arrangement of the included angle between the bidirectional traction hook piece and the unidirectional traction hook piece And a ratio whereby the tooth is caused to undergo root control movement or root control while moving in unison.

The traditional appliance adopts a mode that a single traction hook is bonded with a tooth long axis in an angulation way to implement unidirectional traction, the traction applied by the single traction hook to the tooth can form a moment with a numerical value which is difficult to determine, and meanwhile, a horizontal or vertical component force related to the traction direction is accompanied, and the component force can often cause some unexpected tooth movements even opposite to expected tooth movements, so that the tooth movements cannot be accurately and efficiently controlled; meanwhile, the magnitude of the moment generated by the unidirectional traction hook is insufficient to reach the magnitude required by correcting severely inclined teeth, so that the correction efficiency is weak, and the required treatment course is long.

According to the technical scheme provided by the invention, a pair of equal large reverse forces can be applied to the bidirectional traction hook according to the inclination degree of the teeth, so that the inclined teeth rotate around the tooth resistance center, and the severely inclined teeth can be efficiently corrected. Meanwhile, according to the movement direction and the movement amount of the tooth root and the tooth crown which are expected in clinical practice, a traction force with a corresponding direction is applied to the unidirectional traction hook, so that the accurate movement of the corrected tooth is realized, and the high-efficiency accurate control of the severely inclined tooth is facilitated.

Further, the couple relation can be realized by applying traction forces with the same magnitude and opposite directions on a pair of traction hooks in the bidirectional traction hook piece, and the magnitude of the traction forces can be selected in the range of 1-12 oz.

In a preferred technical scheme, a person skilled in the art can set the included angle between the bidirectional traction hook piece and the unidirectional traction hook piece according to the judgment of the clinical inclination degree of the towed teeth, so that the moment size is gradually reduced in the gradual vertical process of the inclined teeth, and the potential safety hazard caused by excessive tooth movement is eliminated. In order to better illustrate the technical scheme of the present invention, the following will be assisted by specific correction conditions, but the following schemes are not meant to limit the scope of the present invention:

in one preferred technical schemeIn this case, when the molar of the human body is slightly inclined in the mesial direction (long axis and long axis of the toothWhen the intersection angle of the plane perpendicular lines is smaller than 30 DEG):

based on the viewing angle in the direction perpendicular to the tooth bonding surface,

the traction hooks in the unidirectional traction hook piece and the pair of traction hooks in the bidirectional traction hook piece form an included angle of 60-80 degrees in the mesial direction,

Traction forces of the same magnitude but opposite directions are respectively applied to a pair of traction hooks in the bidirectional traction hook piece, the magnitude of the traction forces can be selected in the range of 1-12 oz, and the direction is parallel toA plane.

At this time, if the molar of the human body has a tooth gap in the mesial/distal direction, when it is clinically judged that the molar is required to move entirely in the mesial/distal direction,

traction forces of the same magnitude but opposite directions are respectively applied to a pair of traction hooks in the bidirectional traction hook piece, the magnitude of the traction forces can be selected in the range of 1-12 oz, and the direction is parallel toA plane; and simultaneously applying a traction force of 1-12 oz in a direction toward the mesial/distal direction on the traction hooks in the unidirectional traction hook member;

if the teeth of a human body are in contact with each other in the mesial/distal direction during the righting and tilting process, or because of the up-down movementWhen the clinical judgment requires that the molar be moved integrally in the mesial/distal direction,

in bi-directional towing hooksTraction forces with the same magnitude but opposite directions are respectively applied to a pair of traction hooks, the magnitude of the traction forces can be selected in the range of 1-12 oz, and the direction is parallel toA plane; and simultaneously applying a traction force of 1-12 oz in a direction toward the mesial/distal direction on the traction hooks in the unidirectional traction hook member;

If the human body's teeth-grinding is clinically judged in the whole righting and tilting process that the teeth-grinding is not required to move wholly, a pair of traction hooks in the bidirectional traction hook piece are respectively applied with traction forces with the same magnitude but opposite directions, the magnitude of the traction forces can be selected in the range of 1-12 oz, and the direction is parallel to that of the traction hooksA plane; no traction force is exerted on the traction hooks in the unidirectional traction hooks;

if the molar of human body needs to make extension or depression movement in clinical judgment, 1-12 oz is applied on the traction hook in the unidirectional traction hook piece and faces the root grinding direction orSquare traction force.

In one preferred embodiment, the tooth is inclined in the middle of the molar (tooth long axis and tooth long axis)When the intersection angle of the plane vertical lines is 30-60 DEG:

the traction hook in the unidirectional traction hook piece and the pair of traction hooks in the bidirectional traction hook piece form an included angle of 30-60 degrees in the near-middle direction,

applying phases to a pair of hooks in a bi-directional hitchTraction force with the same magnitude but opposite direction can be selected in the range of 1-12 oz, and the direction is parallel to A plane.

if the human body's teeth-grinding is clinically judged in the whole righting and tilting process that the teeth-grinding is not required to move wholly, a pair of traction hooks in the bidirectional traction hook piece are respectively applied with traction forces with the same magnitude but opposite directions, the magnitude of the traction forces can be selected in the range of 1-12 oz, and the direction is parallel to that of the traction hooks A plane; in one way draw hookNo traction force is applied to the traction hooks in the piece;

In one preferred embodiment, when the molar of the human body is severely mesial-oblique or even mesial-horizontal, the molar is blocked (long axis and long axis of the toothWhen the intersection angle of the plane perpendicular lines is 60-90 DEG):

the traction hook in the unidirectional traction hook piece and the pair of traction hooks in the bidirectional traction hook piece form an included angle of 20-30 degrees in the near-middle direction,

traction forces of the same magnitude but opposite directions are respectively applied to a pair of traction hooks in the bidirectional traction hook piece, the magnitude of the traction forces can be selected in the range of 1-12 oz, and the direction is parallel to A plane; and simultaneously applying 1 to 1 on the traction hooks in the unidirectional traction hook piece2oz and directed toward the mesial/distal direction;

if the molar of human body needs to make extension or depression movement in clinical judgment, 1-12 oz is applied on the traction hook in the unidirectional traction hook piece and faces the root grinding direction or Square traction force.

It is noted that the above preferred embodiments can be used in a plurality of ways according to the correction conditions during the correction of the inclination, for example, when the molar of the patient is moderately inclined in the middle (long axis and long axis)When the intersection angle of the plane vertical lines is 30-60 DEG, adopting a corresponding preferable technical scheme; after correcting a section ofAfter time, the patient's molar returns to a slight mesial tilt (long dental axis and +.>When the intersection angle of the plane vertical lines is smaller than 30 degrees, the preferable technical scheme corresponding to slight mesial inclination can be adopted instead.

In the above preferred technical solution, the example selected is that the molar of the human body has a mesial inclination, and correspondingly, if the molar has a distal inclination, the included angle is formed by one traction hook in the bidirectional traction hook piece and the traction hook in the unidirectional traction hook piece in the distal direction; correspondingly, if the distal/proximal inclination of other teeth occurs, the corresponding adjustment can be made by referring to the technical scheme.

It is noted that, based on the view angle in the direction perpendicular to the tooth bonding surface, the above-mentioned orientation of the pulling hook is based on the general pulling hook structure or form recognized by those skilled in the art, and the orientation of the pulling hook can be regarded as the overall orientation of the pulling hook, for example, the conventional pulling hook including a rod body and a hook body, and the rod body orientation of the pulling hook is regarded as the orientation of the pulling hook, and when the pulling hook is in a non-standard configuration, the rod body in a non-straight rod configuration and the special-shaped hook body are referred to for the conventional pulling hook equivalent thereto. For example, said "making the pulling hook of the unidirectional pulling hook member engage the dentition in which the tooth being pulled is located The plane is vertical ", when the traction hook of the unidirectional traction hook piece is formed by a rod body with a straight rod structure and a question mark hook, the rod body and the tooth row where the traction teeth are positioned are enabled to be +.>The plane is vertical.

In the above preferred technical solution, the overall movement of the pulled tooth in this direction is achieved by applying unidirectional traction forces in different directions to the traction hooks in the unidirectional traction hook member, where the definition of different directions may be a direction that is referred to in the above preferred technical solution and is clinically required to close the interdental space, a direction that is clinically required to perform an extension or depression movement, or a direction that is not referred to in the above technical solution but is clinically determined to be required to perform an overall movement.

In this context, the three-way pulling hook is attached to the tooth-attaching surface of the tooth to be pulled, wherein the tooth-attaching surface is commonly used as the clinical crown center point of the tooth, i.e., the intersection point of the clinical crown long axis and the crown near-far-middle contact line,the plane is coated by the first permanent molar on the upper part and the lower part>Middle point and upper and lower middle incisors are covered by +.>A line connecting the midpoints. (Chen Yangxi, orthodontics-basic, technical and clinical, 2012, people health press)

In one of the technical schemes, the three-way traction hook for the dental correction further comprises a top cover piece, wherein the top cover piece is used for sealing the top ends of the two-way traction hook connector or the one-way traction hook connector, so that discomfort of the oral cavity of a human body is reduced, and meanwhile, the connecting seat head, the two-way traction hook connector and the one-way traction hook connector can be used together as a traction element winding column.

In one technical scheme, in order to maintain the included angle between the traction hook in the unidirectional traction hook piece and the pair of traction hooks in the bidirectional traction hook piece, the traction hook in the unidirectional traction hook piece and the pair of traction hooks in the bidirectional traction hook piece can be selected, and an angle retaining piece is arranged between the traction hook in the unidirectional traction hook piece and the pair of traction hooks in the bidirectional traction hook piece, and the angle retaining piece can refer to a conventional structure in the prior art, such as an angle fixing buckle; optionally, a grind is provided at the interface between the bi-directional hitch coupler and the unidirectional hitch coupler, and/or a bayonet arrangement is provided, as is conventional in the art.

Further, in the clinical correction process, the situation that the teeth are slightly inclined so that the whole tooth movement is not involved in the whole correction process is also provided, so that the unidirectional traction hook piece can be directly removed to reserve the bidirectional traction hook piece for use:

A two-way traction hook for tooth correction comprises a base piece and a two-way traction hook piece which are fixedly connected with each other;

the base piece comprises a connecting seat head and an adhesive pedestal used for being adhered to the adhesive surface of the tooth, and the base piece and the bidirectional traction hook piece are fixedly connected with each other through the fixed connection between the connecting seat head and the bidirectional traction hook connector.

The two-way traction hook for tooth correction has the same correction method as the three-way traction hook for tooth correction, and the traction hook in the two-way traction hook piece are required to be ensuredThe planes have an included angle of 0-80 deg..

Based on the innovation and principle description of the invention, it can be known that in the above technical scheme, the relationship of the included angle between the traction hook in the unidirectional traction hook piece and the pair of traction hooks in the bidirectional traction hook piece is one of the important invention points, but in the above technical scheme, the included angle relationship is provided with a risk of being easily changed by external force due to the adjustability of the included angle relationship based on the technical idea that the whole correction process is convenient for a user to adjust correspondingly according to the condition of a patient, and the risk is reduced by some structural improvements, but the overall instrument cost is increased.

Therefore, the inventor proposes big data arrangement based on clinical sampling, and takes the most conventional included angle relation as a preferable range of fixed included angle relation:

a three-way traction hook for tooth correction comprises a base piece and a three-way traction hook piece which are fixedly connected with each other;

the three-way traction hook piece is formed by fixing three traction hooks and a three-way traction hook connector, wherein the three traction hooks are provided with a pair of first traction hooks and second traction hooks with opposite traction directions, and a third traction hook;

the base piece comprises a connecting seat head and an adhesive pedestal used for being adhered to the adhesive surface of the tooth, and the base piece and the three-way traction hook piece are fixedly connected with each other through the fixed connection between the connecting seat head and the three-way traction hook connector;

in the direction perpendicular to the tooth bonding surface, the setting direction of the third traction hook in the three-way traction hook component and the first traction hook or the second traction hook form an included angle respectively, wherein the smaller included angle is any one of 29-31 degrees, 39-41 degrees, 44-46 degrees, 49-51 degrees, 59-61 degrees or 69-71 degrees.

In one of the technical schemes, the base part and the three-way traction hook part can be respectively prepared, or the base part and the three-way traction hook part can be directly prepared through an integral molding process to form an integral body in an assembly and construction way.

The technical scheme of the invention has the following beneficial effects:

(1) The three-way traction hook for tooth correction provided by the invention can be used for efficiently controlling root movement or controlling root and simultaneously integrally moving inclined teeth, so that the inclined teeth, especially the severely inclined teeth, can be corrected with high efficiency and high efficiency, and the orthodontic treatment time is greatly shortened; the accuracy of mechanical control can be improved, side effects in the correction process can be prevented, and the correction safety can be improved.

(2) Based on the preferred technical scheme provided by the invention, a person skilled in the art can set the included angle between the bidirectional traction hook piece and the unidirectional traction hook piece according to the judgment of the clinical inclination degree of the teeth, so that the moment size is gradually reduced in the process of gradually and vertically inclining the teeth, and the potential safety hazard caused by excessive movement of the teeth is eliminated.

(3) When the three-way traction hook for tooth correction is used, through the cooperation of applying force couple to the two-way traction hook piece and applying traction force to the one-way traction hook piece, accurate control of the overall movement direction and the movement degree of the teeth can be realized, and correction details such as tooth gap closing, tooth verticality, occlusion relation adjustment and the like can be conveniently and safely implemented by technicians.

Drawings

Fig. 1 is a schematic view of a three-way hook for orthodontic treatment according to embodiment 1 of the present invention, which does not include a top cover member.

Fig. 2 is a schematic structural view of a three-way traction hook for orthodontic treatment according to embodiment 1 of the present invention.

Fig. 3 is an exploded view of a three-way hitch for orthodontic treatment according to embodiment 1 of the present invention.

Fig. 4 is a schematic view of the bonding surface structure of the bonding base in the three-way traction hook for dental correction according to embodiment 1 of the present invention.

Fig. 5 is a schematic structural view of the three-way hook for orthodontic treatment according to embodiment 1 of the present invention, which does not include a top cover member and is perpendicular to the view angle of the bonding surface of teeth.

Fig. 6 is a schematic view of a three-way hook for orthodontic treatment according to embodiment 1 of the present invention. In the drawing, the direction indicated by the arrow is the traction direction, and traction is performed in a mode shown in the drawing, so that the aim of closing the tooth gap by integrally moving the teeth while tilting the teeth vertically is fulfilled. Note that the topography of the pulled teeth is merely illustrative.

Fig. 7 is a schematic view of a three-way hook for orthodontic treatment according to embodiment 1 of the present invention. In the drawing, the direction indicated by the arrow is the traction direction, and traction is performed in a mode shown in the drawing, so that the aim of closing the tooth gap by integrally moving the teeth while tilting the teeth vertically is fulfilled. The bidirectional traction hook and the unidirectional traction hook can be installed upside down to obtain different question mark hook orientations. Note that the topography of the pulled teeth is merely illustrative.

Fig. 8 is a schematic structural view of a bidirectional traction hook for orthodontic treatment according to embodiment 2 of the present invention, which does not include a top cover member.

Fig. 9 is a schematic structural view of a bidirectional traction hook for orthodontic treatment according to embodiment 2 of the present invention.

Fig. 10 is a schematic view of a bidirectional traction hook for orthodontic treatment according to embodiment 2 of the present invention in use. In the drawing, the direction indicated by the arrow is the traction direction, and traction is performed in a manner shown in the drawing, so that the purpose of preventing additional movement while tilting teeth vertically is achieved. Note that the topography of the pulled teeth is merely illustrative.

Fig. 11 is a schematic structural view of a three-way traction hook for orthodontic treatment according to embodiment 3 of the present invention.

Detailed Description

For a further understanding of the present invention, preferred embodiments of the invention are described below in conjunction with the examples, but it should be understood that these descriptions are merely intended to illustrate further features and advantages of the invention and are not limiting of the invention claims. Those skilled in the art can, with the benefit of this disclosure, suitably modify the process parameters to achieve this. It is expressly noted that all such similar substitutions and modifications will be apparent to those skilled in the art, and are deemed to be included within the present invention. While the methods and applications of this invention have been described in terms of preferred embodiments, it will be apparent to those skilled in the relevant art that variations and modifications can be made in the methods and applications described herein, and in the practice and application of the techniques of this invention, without departing from the spirit or scope of the invention. While the following terms are believed to be well understood by those of ordinary skill in the art, the following definitions are set forth to aid in the description of the presently disclosed subject matter.

In one aspect, the invention provides a three-way traction hook for tooth correction, which comprises a base piece, a two-way traction hook piece and a one-way traction hook piece which are fixedly connected with each other;

In one embodiment, the towing hook is mainly composed of a hook body and a rod body. Wherein, the one end of the rod body is connected with the hook body, and the other end is connected with the two-way traction hook connector/the one-way traction hook connector.

In one embodiment, the structure of the hook body may be a curved configuration having a tip and an open structure, such as a question mark hook; an annular configuration without a tip, such as a circular ring hook, is also possible.

In one embodiment, the rod body may have a straight rod configuration or a non-straight rod configuration. However, it should be noted that when the rod body is in a non-straight rod configuration, the force and the force applied to the two ends of the rod body should be ensured to be consistent with those of the rod body in the straight rod configuration, so as to achieve the same technical effect.

In one embodiment, the sizes and materials of the hook body and the rod body can be traction hooks which are conventionally used in the technical field of reference oral medical orthodontic, and the following technical scheme can be adopted:

in one preferred embodiment, the hook body and the rod body are made of metal materials, including but not limited to stainless steel materials (it should be noted that, stainless steel is currently commonly used in the technical field of orthodontic appliances for dentistry as a material for appliances, and specific stainless steel types can refer to the selection of appliances in the same field); the length of the rod body is 1-8 mm, such as 1.5mm, 2mm, 2.5mm, 3mm, 4mm, 5mm, 6mm, 6.5 mm, 7mm and 7.5mm; the outer diameter of the hook body is not more than 6mm, such as 1mm, 2mm, 3mm, 4mm and 5mm, so as to be suitable for being placed in the oral cavity of a human body as much as possible.

In this context, the base member comprises a connecting head and an adhesive abutment for adhering to the tooth adhesive surface, wherein the adhesive abutment is adapted to adhere to the tooth adhesive surface to secure the three-way pulling hook provided in the present technology in the mouth of a person. Based on the above functional purposes, in one embodiment, the bonding base may refer to other bonding bases disclosed in the art or structures playing the same role of bonding and fixing, and the following technical solutions may also be adopted:

in a preferred embodiment, the bonding pad comprises a cylinder or a polygonal shape, preferably a cylinder.

In one preferred embodiment, in order to enhance the bonding effect, the bonding surface of the bonding pedestal is a non-smooth plane, for example, a grind pattern is provided to enhance the bonding effect of the adhesive.

In one preferred embodiment, the outer diameter of the bonding pedestal is 2-6 mm, such as 2.5mm, 3mm, 3.5mm, 4mm, 5mm, 5.5mm; the thickness is 0.3 to 1.5mm, for example 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm.

In one preferred embodiment, the connecting seat head, the bidirectional traction hook connector and the unidirectional traction hook connector are in a circular cylinder shape with internal threads, have uniform inner diameters and are fixed in series through screws. Further preferably, the outer diameters of the connecting seat head, the bidirectional traction hook connector and the unidirectional traction hook connector are consistent, and the connecting seat head, the bidirectional traction hook connector and the unidirectional traction hook connector are fixedly connected in series through screws to form a cylinder shape.

In one embodiment, the connecting seat head, the bidirectional traction hook connector and the unidirectional traction hook connector are provided with annular protrusions at the fixed connection positions of the connecting seat head, the bidirectional traction hook connector and the unidirectional traction hook connector, so that the embedded and fixed functions are achieved, the stability of fixed connection is further improved, and the bidirectional traction hook piece and the unidirectional traction hook piece are prevented from rotating relatively under a fixed state. Further, a grind may be provided on the annular protrusion to further prevent the occurrence of relative rotation.

In one preferred embodiment, the outer diameter of the connector head, the bidirectional traction hook connector and the unidirectional traction hook connector is 0.5-3 mm, such as 0.6mm, 0.8mm, 1.0mm, 1.2mm, 1.4mm, 1.5mm, 1.6mm, 1.8mm, 2.0mm, 2.2mm, 2.5mm and 2.8mm; the height is 1-6 mm, such as 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, and is suitable for being placed in the oral cavity of human body as much as possible.

On the other hand, the invention provides a correction method of a three-way traction hook for tooth correction, which mainly comprises the following steps:

In general, and when the vestibular sulcus of the pulled tooth is clinically judged to have a deeper feature, or when the pulled tooth is clinically required to be straightened and simultaneously performs a mesial or distal overall movement or a root control movement, the pulling hook of the unidirectional pulling hook member and the dentition where the pulled tooth is located are preferably made to beThe plane is vertical. Clinically, the teeth are pulled and +.>The angle of the plane is continuously changed, so that if the pulling hook of the unidirectional pulling hook piece is parallel to the tooth long axis of the pulled tooth, a plurality of variables (tooth inclination angle, a pair of pulling hooks and +. >Plane angle, traction direction) calculation and continuous adjustment, thereby greatly increasing the setting and use difficulty of the three-way traction hook. However, if the technical scheme that the included angle between the long axis of the traction hook of the unidirectional traction hook piece and the long axis of the tooth body of the towed tooth is 0-45 degrees is adopted, the hook body of the unidirectional traction hook can be positioned at a larger distance from the gingival of the center of tooth resistance to generate larger root control moment, and the root control movement of the towed tooth is facilitated, so that the tooth straightening effect is better.

In the above technical solution, when the orientation of the pulling hook of the unidirectional pulling hook member is determined based on the angle of view in the direction perpendicular to the tooth bonding surface, the pulling hook of the unidirectional pulling hook member and the pair of pulling hooks of the bidirectional pulling hook member form two clampsThe smaller included angle of the angles is a fixed value which is selected in the range of 20-80 degrees in advance, such as 25 degrees, 30 degrees, 35 degrees, 40 degrees, 45 degrees, 50 degrees, 55 degrees, 60 degrees, 65 degrees, 70 degrees and 75 degrees. Thus in the above technical solution, a pair of towing hook orientations in the bidirectional towing hook exist andin the case where the planes are parallel, if intra-jaw traction is generated, a couple cannot be formed, and therefore, a mode of performing inter-jaw traction may be selected to apply the couple.

The couple is formed by adding a pair of forces with equal magnitude and opposite directions on the bidirectional traction hook piece, so that the inclined teeth can rotate around the center of resistance, and the effect of vertically inclining the teeth is achieved; at the same time, can apply a force parallel to the unidirectional traction hookForce in the plane direction causes the teeth to move integrally due to the fact that the force application points are close to the resistance centers of the teeth; the length of the rod body of the traction hook and the included angle between the bidirectional traction hook piece and the unidirectional traction hook piece are controlled, so that the magnitude and the ratio of force couple and force can be controlled, and the teeth can be enabled to move in a root controlling manner or integrally move at the same time.

Further, the couple relationship may be achieved, in one embodiment, by applying traction forces of the same magnitude but opposite directions to each other to a pair of the bi-directional traction hooks, the traction forces may be selected to be in the range of 1 to 12oz, such as 2oz, 3oz, 4oz, 5oz, 6oz, 7oz, 8oz, 9oz, 10oz, 11oz.

In a preferred embodiment, a person skilled in the art can set the magnitude of the included angle between the bidirectional traction hook and the unidirectional traction hook according to the judgment of the clinical inclination degree of the teeth to be pulled, so that the moment magnitude shows a gradually decreasing trend in the process of gradually erecting the inclined teeth, and the potential safety hazard caused by excessive tooth movement is eliminated. In order to better illustrate the technical scheme of the present invention, the following will be assisted by specific correction conditions, but the following schemes are not meant to limit the scope of the present invention:

In one preferred embodiment, when the molar of the human body is slightly mesial-mesial (long axis of tooth and long axis of toothWhen the intersection angle of the plane perpendicular lines is smaller than 30 DEG):

in a bi-directional towing hookThe traction force is applied to a pair of traction hooks with the same magnitude but opposite directions, the magnitude of the traction force can be selected in the range of 1-12 oz, and the direction is parallel toA plane.

if the teeth of a human body are in contact with each other in the mesial/distal direction during the righting and tilting process, or because of the up-down movement When the clinical judgment requires that the molar be moved integrally in the mesial/distal direction,

In one preferred embodiment, the tooth is inclined in the middle when the molar of the human body is moderately mesial (long axis and long axis of toothWhen the intersection angle of the plane vertical lines is 30-60 DEG:

traction forces of the same magnitude but opposite directions are respectively applied to a pair of traction hooks in the bidirectional traction hook piece, the magnitude of the traction forces can be selected in the range of 1-12 oz, and the direction is parallel toA plane; and simultaneously pulling in unidirectional pulling hooksApplying a traction force of 1-12 oz to the hook in a direction toward the mesial/distal direction;

In one preferred embodiment, when the molar of the human body develops severe mesial-tilt or even mesial-horizontal resistance (long axis of tooth vsWhen the intersection angle of the plane perpendicular lines is 60-90 DEG):

so that the traction hook of the unidirectional traction hook piece and the dentition of the traction tooth are positioned The plane is vertical and the plane is vertical,

traction forces of the same magnitude but opposite directions are respectively applied to a pair of traction hooks in the bidirectional traction hook piece, the magnitude of the traction forces can be selected in the range of 1-12 oz, and the direction is parallel to A plane; and simultaneously applied to the draw hooks in the unidirectional draw-hook memberAdding a traction force of 1-12 oz in a direction towards the mesial/distal direction;

It is noted that in the above preferred embodiment, during the righting and tilting process, a plurality of schemes can be adopted according to the correction condition, for example, when the molar of the patient is moderately inclined in the middle (long axis and long axis of tooth)When the intersection angle of the plane vertical lines is 30-60 DEG, adopting a corresponding preferable technical scheme; after a period of time of correction, the patient's molar returns to a slight mesial tilt (long dental axis and +.>When the intersection angle of the plane vertical lines is smaller than 30 degrees, the preferable technical scheme corresponding to slight mesial inclination can be adopted instead.

In the above preferred embodiment, the selected example is that the molar of the human body has a mesial inclination, and correspondingly, if the molar has a distal inclination, the included angle is formed by one traction hook in the bidirectional traction hook piece and the traction hook in the unidirectional traction hook piece in the distal direction; correspondingly, if the distal/proximal inclination of other teeth occurs, the corresponding adjustment can be made by referring to the technical scheme.

Note that vertical tooth basedThe above-mentioned orientation of the hook is based on a general hook structure or form recognized by those skilled in the art, and the orientation of the hook may be regarded as the overall orientation of the hook, for example, a conventional hook including a rod body and a hook body, and the rod body orientation may be regarded as the orientation of the hook, and the hook may be set with reference to a conventional hook equivalent thereto when the hook is configured in a non-standard manner, a rod body configured in a non-straight manner, or a special hook body. For example, said "making the pulling hook of the unidirectional pulling hook member engage the dentition in which the tooth being pulled is locatedThe plane is vertical ", when the traction hook of the unidirectional traction hook piece is formed by a rod body with a straight rod structure and a question mark hook, the rod body and the tooth row where the traction teeth are positioned are enabled to be +. >The plane is vertical.

In the above preferred embodiment, the unidirectional traction force in different directions is applied to the traction hooks in the unidirectional traction hook member, so that the overall movement of the pulled teeth in the direction is realized, and the definition of the different directions may be the direction in which the gap between teeth is clinically required to be closed, the direction in which the extension or depression movement is clinically required in the above preferred embodiment, or the direction in which the overall movement is not involved in the above preferred embodiment but is clinically judged to be required.

In one embodiment, the three-way traction hook for tooth correction further comprises a top cover piece, wherein the top cover piece is used for sealing the top end of the two-way traction hook connector or the one-way traction hook connector, so that discomfort of a human oral cavity is reduced, and meanwhile, the connecting seat head, the two-way traction hook connector and the one-way traction hook connector can be used together as a traction element winding column.

In one embodiment, in order to maintain the angle between the traction hook in the unidirectional traction hook piece and the pair of traction hooks in the bidirectional traction hook piece, the traction hook in the unidirectional traction hook piece and the pair of traction hooks in the bidirectional traction hook piece can be selected, and an angle retaining piece is arranged between the traction hook in the unidirectional traction hook piece and the pair of traction hooks in the bidirectional traction hook piece, and the angle retaining piece can refer to a conventional structure in the prior art, such as an angle fixing buckle; optionally, a grind is provided at the interface between the bi-directional hitch coupler and the unidirectional hitch coupler, and/or a bayonet arrangement is provided, as is conventional in the art.

in yet another aspect, the present invention provides a bidirectional traction hook for dental appliance, comprising a base member and a bidirectional traction hook member fixedly connected to each other;

The two-way traction hook for tooth correction has the same correction method as the three-way traction hook for tooth correction, and the traction hook in the two-way traction hook piece are required to be ensuredThe planes have an included angle of 0-80 degrees.

In yet another aspect, the present invention provides a three-way hitch for dental appliances, comprising a base member, a three-way hitch member fixedly attached to one another;

In one embodiment, the base part and the three-way traction hook part can be respectively prepared, or the base part and the three-way traction hook part can be directly prepared through an integral molding process to form an integral body in an assembly and construction mode.

The present application will be explained in further detail with reference to examples. However, those skilled in the art will appreciate that these examples are provided for illustrative purposes only and are not intended to limit the present application.

Example 1

As shown in fig. 1 to 5, the three-way traction hook for tooth correction of the embodiment comprises a base part 1, a two-way traction hook part 2 and a one-way traction hook part 3 which are fixedly connected with each other;

the bidirectional traction hook piece 2 is formed by fixing a pair of traction hooks A2-2 with opposite traction directions and a bidirectional traction hook connector 2-1;

the unidirectional traction hook piece 3 is formed by fixing a single B traction hook 3-2 and a unidirectional traction hook connector 3-1;

the base piece 1 comprises a connecting seat head 1-2 and an adhesive pedestal 1-1 used for being adhered to the adhesive surface of the teeth, and the base piece, the bidirectional traction hook piece and the unidirectional traction hook piece are fixedly connected with each other through the fixed connection between the connecting seat head 1-2 and the bidirectional traction hook connector and the unidirectional traction hook connector;

in the direction perpendicular to the tooth bonding surface, the included angle between the B traction hook 3-2 in the unidirectional traction hook piece 3 and the pair of A traction hooks 2-2 in the bidirectional traction hook piece 2 is 60 degrees.

The A, B traction hooks (2-2, 3-2) mainly comprise hook bodies and rod bodies. Wherein, the one end of the rod body is connected with the hook body, and the other end is connected with the two-way traction hook connector/the one-way traction hook connector.

The structure of the hook body is a question mark hook, and the structure of the rod body is a straight rod structure.

The hook body and the rod body are made of stainless steel materials; the length of the rod body is 4mm, and the outer diameter of the hook body is 3mm, so that the hook body is suitable for being placed in the oral cavity of a human body as much as possible.

The bonding pedestal 1-1 is cylindrical, has an outer diameter of 4mm and a height of 0.5mm.

The bonding surface of the bonding pedestal 1-1 is a non-smooth plane and is provided with grind lines so as to strengthen the bonding effect of the adhesive.

The connecting seat head 1-2, the bidirectional traction hook connector 2-1 and the unidirectional traction hook connector 3-2 are in a circular cylinder shape with internal threads, the internal diameter and the external diameter are consistent, and the three are connected in series and fixed through screws to form a cylinder shape. The connecting seat head 1-2, the two-way traction hook connector 2-1 and the one-way traction hook connector 3-2 have the outer diameter of 2.5mm and the height of 1mm, so that the connecting seat head is suitable for being placed in the oral cavity of a human body as much as possible.

The three-way traction hook for tooth correction further comprises a top cover piece 4, wherein the top cover piece 4 is used for closing the top end of the two-way traction hook connector, so that discomfort of a human oral cavity is reduced, and meanwhile, the connecting seat head, the two-way traction hook connector and the one-way traction hook connector can be used together as a traction element winding column.

Example 2

As shown in fig. 8 to 9, the bidirectional traction hook for dental correction of the present embodiment includes a base member and a bidirectional traction hook member fixedly connected to each other;

the bidirectional traction hook piece 2 is formed by fixing a pair of traction hooks A with opposite traction directions and a bidirectional traction hook connector;

the base piece 1 comprises a connecting seat head and an adhesive pedestal used for being adhered to the adhesive surface of the teeth, and the base piece and the bidirectional traction hook piece are fixedly connected with each other through the fixed connection between the connecting seat head and the bidirectional traction hook connector.

The traction hook A mainly comprises a hook body and a rod body. Wherein, the one end of the rod body is connected with the hook body, and the other end is connected with the two-way traction hook connector/the one-way traction hook connector.

The hook body and the rod body are made of stainless steel materials; the length of the rod body is 6mm, and the outer diameter of the hook body is 4mm, so that the hook body is suitable for being placed in the oral cavity of a human body as much as possible.

The bonding pedestal is cylindrical, the outer diameter is 3mm, and the height is 1mm.

The connecting seat head and the bidirectional traction hook connector are in a circular cylinder shape with internal threads, the internal diameter and the external diameter are consistent, and the connecting seat head and the bidirectional traction hook connector are connected in series and fixed through screws to form a cylinder shape. The outer diameter of the connecting seat head and the two-way traction hook connector is 2mm, and the height is 1.5mm, so that the connecting seat head and the two-way traction hook connector are suitable for being placed in the oral cavity of a human body as much as possible.

The two-way traction hook for tooth correction further comprises a top cover piece 4, wherein the top cover piece 4 is used for closing the top end of the two-way traction hook connector, so that discomfort of a human oral cavity is reduced, and meanwhile, the connecting seat head and the two-way traction hook connector can be used together as a traction element winding column.

Example 3

As shown in fig. 11, the three-way traction hook for tooth correction of the embodiment comprises a base piece 1 and a three-way traction hook piece 5 which are fixedly connected with each other;

the three-way traction hook piece 5 is formed by fixing three traction hooks and a three-way traction hook connector, wherein the three traction hooks are provided with a pair of first traction hooks and second traction hooks with opposite traction directions and a third traction hook;

the base piece 1 comprises a connecting seat head and an adhesive pedestal used for being adhered to the adhesive surface of the tooth, and the base piece and the three-way traction hook piece are fixedly connected with each other through the fixed connection between the connecting seat head and the three-way traction hook connector;

and in the direction perpendicular to the tooth bonding surface, the three-way traction hook piece is provided with a third traction hook, wherein the arrangement direction of the third traction hook is 30 degrees with the first traction hook or the second traction hook.

The first traction hook, the second traction hook and the third traction hook mainly comprise a hook body and a rod body. Wherein, the one end of the rod body is connected with the hook body, and the other end is connected with the two-way traction hook connector/the one-way traction hook connector.

The hook body and the rod body are made of stainless steel materials; the length of the rod body is 3mm, and the outer diameter of the hook body is 2mm, so that the hook body is suitable for being placed in the oral cavity of a human body as much as possible.

The bonding pedestal is cylindrical, the outer diameter is 5mm, and the height is 0.3mm.

The outer diameter of the connecting seat head and the three-way traction hook connector is 1mm, and the height is 1mm, so that the connecting seat head and the three-way traction hook connector are suitable for being placed in the oral cavity of a human body as much as possible.

The base piece and the three-way traction hook piece are integrated, and the integrated structure of the base piece and the three-way traction hook piece is directly prepared through an integrated molding process.

The foregoing examples are illustrative of the present invention and are not intended to be limiting, and any other changes, modifications, substitutions, combinations, and simplifications that do not depart from the spirit and principles of the invention are intended to be equivalent and are within the scope of the present invention.

Claims

1. The three-way traction hook for tooth correction is characterized by comprising a base piece, a two-way traction hook piece and a one-way traction hook piece which are fixedly connected with each other;

the bidirectional traction hook piece is formed by fixing a pair of traction hooks with opposite traction directions and a bidirectional traction hook connector; a couple of forces with equal magnitude and opposite directions are added on the bidirectional traction hook piece to form a couple relation;

2. The three-way hitch for dental appliance of claim 1, wherein: the traction hook mainly comprises a hook body and a rod body;

the structure of the hook body can be a bending structure with a terminal and an opening structure, or a ring-shaped structure without a terminal;

the structure of the rod body can be a straight rod configuration or a non-straight rod configuration.

3. The three-way hitch for dental appliance of claim 2, wherein: the length of the rod body is 1-8 mm, and the outer diameter of the hook body is not more than 6mm.

4. The three-way hitch for dental appliance of claim 1, wherein: the outer diameter of the bonding pedestal is 2-6 mm, and the thickness is 0.3-1.5 mm.

5. The three-way hitch for dental appliance of claim 1, wherein: the connecting seat head, the bidirectional traction hook connector and the unidirectional traction hook connector are in a circular cylinder shape with internal threads, and the internal diameters of the circular cylinder shape are consistent; the connecting seat head, the bidirectional traction hook connector and the unidirectional traction hook connector are identical in outer diameter, and are fixedly connected in series through screws to form a cylinder.

6. The three-way hitch for dental appliance of claim 1 or 5, wherein: the outer diameter of the connecting seat head, the bidirectional traction hook connector and the unidirectional traction hook connector is 0.5-3 mm, and the height is 1-6 mm.

7. The three-way traction hook for tooth correction is characterized by comprising a base piece and a three-way traction hook piece which are fixedly connected with each other;

the three-way traction hook piece is formed by fixing three traction hooks and a three-way traction hook connector, wherein the three traction hooks are provided with a pair of first traction hooks and second traction hooks with opposite traction directions, and a third traction hook; a couple relation can be formed by adding a pair of forces with equal magnitude and opposite directions on the first traction hook and the second traction hook;