Orthodontic braces

Abstract

The invention relates to orthodontics. An orthodontic bracket comprises a base with a contact surface against the anterior surface of a patient's tooth, and a housing connected to the base and positioned above the base. The housing contains an open slot, the longitudinal axis of which is horizontal, used to accommodate an elastically deformable orthodontic archwire. Through channels, each smaller in cross-section than the slot cross-section, are formed in the housing above and along the slot and below and along the slot, for accommodating additional elastically deformable archwires. 2 fig.

Description

[0001] The utility model relates to orthodontics, in particular, to an orthodontic bracket device containing a bracket substrate that is attached to the base of the bracket or made integral with it, and intended for application to the surface of the patient's tooth under the action of an elastic component of the orthodontic arch.

[0002] Dental braces are a type of orthodontic appliance that has gained immense popularity over the past few decades. This treatment is effective, achieving straight teeth in a short period of time, and correcting orthodontic problems is possible at any age. Orthodontic appliances consist of brackets made of metal, ceramic, or other materials. The system is attached to the outer or inner surfaces of the teeth. All elements are activated by a special thin wire called an orthodontic arch.

[0003] A fixed orthodontic system is necessary to correct pathologies associated with the incorrect positioning of teeth. For example, correction (of the relationship of the dental arches) - a violation of the structure of the dental arches: one of the jaws may be underdeveloped (micrognathia) or protrude too far forward (macrognathia); a person has pronounced facial asymmetry, unable to fully close the upper and lower elements of the maxillofacial apparatus. Correction of crowding - when there is not enough space in the mouth, teeth overlap each other. Due to the lack of space, the crowns are curved and change their natural position. Correction of tremas - wide spaces between adjacent teeth. In addition, the anomaly can be symmetrical or asymmetrical. In the first case, the incisors, canines, and molars are displaced from the center at equal intervals. In the second case, one crown is displaced further than the others.

[0004] Orthodontic brackets are used in conjunction with other elements such as an orthodontic archwire (a wire with the elasticity of a material in the form of a round rod or a rectangular section like a tape) to provide first, second and third order movements of the patient's tooth without clinically predetermined manipulation of the orthodontic archwire, which is placed in a transversely located orthodontic archwire slot.

[0005] In general, first-order movements are considered tooth rotation and / or reciprocating movements. Second-order movements are often referred to as "tipping" of the tooth root during mesial and / or distal angle adjustments or raising and / or lowering the tooth position. Third-order movements, or "force couples," result in the transfer of "torque," which causes the axial tilt of the tooth from a vertical or non-vertical orientation to the final desired position.

[0006] Nature allows teeth to change position, either spontaneously or under the influence of external forces. This property makes orthodontic treatment with braces possible. The principle is as follows.

[0007] 1. Based on the patient's clinical picture, the doctor plans the movement trajectory for each tooth, with one bracket responsible for each tooth.

[0008] 2. During the process of fixing the braces, the locks are connected to each other by an archwire with or without shape memory, which it tends to take over time.

[0009] 3. Under the action of the elastic component of the arch, the dental arch begins to take the desired position.

[0010] 4. During the treatment, the arch is replaced with a harder one to increase the impact.

[0011] The bracket system consists of: brackets (a small element that is glued to the tooth), an orthodontic arch (the active element of the system, with the help of which the teeth are set in motion under the action of the elastic component of the material, tube locks installed on the outer teeth as supports for attaching the ends of the arch, and auxiliary elements (ligatures, springs, elastics, etc.) create additional forces and support points when correcting the bite.

[0012] Modern braces are small and practically unnoticeable in the mouth. Brackets, as basic structural elements, are bonded to the teeth with a base or backing using a special filling material or adhesive, which hardens under ultraviolet light. The basic principle of braces is the use of an orthodontic archwire, either with or without memory (creating a force on the tooth in the distal direction, which presses on the brackets so that they ultimately move the teeth into the desired position). The orthodontic archwire is initially bent to the anatomically correct shape of the dental arch, after which it is bonded to the crooked teeth. This process is slow but effective (depending on the severity of the oral problems). The archwire bends back to its original position, moving the misaligned teeth along with it.

[0013] The purpose of a bracket is to transfer the force transmitted by the orthodontic archwire inserted into the bracket system to the tooth. The bracket itself in this bracket system consists of at least a base, a slot, and wings. The bracket base is bonded to the tooth enamel using a composite material. The orthodontic archwire is inserted into the bracket slot. Some types of brackets have an additional slot for auxiliary elements. Slots come in only two sizes - 0.018 and 0.022 - for archwires of the corresponding size. Ligatures are attached to the bracket using the wings. These auxiliary elements secure the archwire to the bracket. Brackets can have 2 wings (oblong projections extending along the sides of the slot and across it) or 4 wings (projections located below and above the slot on its sides). On some teeth, there may be a small hook on the wing of the bracket, which can be used to attach a so-called elastic traction during treatment.

[0014] In some braces, the archwire is secured using ligatures that have support on the wings, or using a locking unit that snaps the archwire from above after it is placed in the groove (self-ligating braces).

[0015] Braces are fixed brackets with a groove and "wings" attached to the teeth. The system works by allowing the orthodontic archwire to return to its original position. The straightening archwire exerts pressure on the brackets, causing teeth to move. Fixed retainers and aligners stabilize the result during the final stage of treatment.

[0016] The basis of bite correction is the mechanism of action of weak forces and the movement of teeth in accordance with the curves and shape of the arch.

[0017] Brackets exert different forces on teeth depending on the ligation type (ligation is the method by which the archwire is secured to the bracket). In self-ligating brackets, the archwire fits into a slot in the base and can be closed by a flap on the bracket itself. In ligature brackets, the archwire is secured to the wings with a ligature (a rubber band or wire). The ligature holds the archwire tightly in the slot, creating additional friction, forcing the archwire to overcome significant resistance when moving teeth. Treatment with ligature brackets can be more painful because more aggressive pressure is applied to the roots and ligaments of the teeth. In self-ligating systems (with a lock), the archwire slides freely in the slot and exerts gentle forces on the teeth. This treatment method allows for tooth movement and detailed results without excessive pressure.

[0018] The arch can be made of elastic steel (standard option) or the metal arch can have a “shape memory”: it straightens, pulls the braces along with it and moves the teeth in the desired direction.

[0019] To understand how braces work, let's look at the biological and physiological processes that occur during tooth movement. Teeth are located in alveoli—natural depressions in the jawbones of the skull. The root of each tooth is surrounded by periodontal fibers that hold the tooth in its socket. These fibers also act as shock absorbers, allowing the tooth to perform micro-movements in all directions. After the bracket is secured and the archwire is installed, force begins to act on the root. To ensure slow and painless tooth movement, gentle, continuous force is applied. Due to root movement, space needs to be created within the alveolus. To achieve this, osteoclasts begin to break down the bone where the root meets the alveolus wall. Osteoclasts are specialized cells that remove bone tissue. On the opposite side, osteoblasts produce new bone to fill the vacated space.Under the influence of osteoclasts and osteoblasts, the balance of formation and destruction of bone tissue ensures the progressive movement of teeth.

[0020] It follows that the basic element in brace systems is the orthodontic archwire. Its property, as an elastically deformable element, to return to its original shape after the removal of external force, is used to move teeth to a position in the dental arch where elastic forces cease to act on the archwire material. When a single orthodontic archwire is used on all teeth in a dental arch, the pressure forces on each tooth are approximately equalized, despite the fact that the teeth themselves may be in different positions within the arch. In this case, adjustments to the pressure on a tooth whose position differs significantly from that of the other teeth in the archwire are required.For this purpose, some brackets have through-holes in the wings parallel to (above) the central slot. These holes can be used to insert an additional archwire of lower elasticity. The pressure from this archwire, combined with the pressure from the base archwire, increases the force applied to the tooth compared to the pressure applied to the remaining teeth in the dental arch. Such a bracket is described in the ORMCO Catalog of the Orthodontic Research & Manufacturing Company, 2023, model DAMON"Q bracket, pp. 6 and 8 (this solution was adopted as a prototype).

[0021] This bracket contains a base in the form of a tooth support platform, which is attached to the tooth surface in its central area through an adhesive or glue, and which carries the body of the bracket, in which a groove is made, directed across the tooth and used to place an orthodontic arch, a lock that closes the groove after the arch is placed in it, while in the upper part of the body above the groove there is a through hole, smaller in size than the cross-section of the groove when the lock is closed and located parallel to the longitudinal axis of the groove.

[0022] This through-hole is used to accommodate an additional archwire of lower elasticity to regulate pressure on the tooth. It is also used when using pediatric braces to accommodate an archwire with lower compression forces (instead of a slotted archwire). The additional hole provides more flexibility in complex clinical situations, including canine dystopia, blocked lateral incisors, and others. Removable hooks can be installed, partial archwires can be used, and microimplants can be activated at any stage, following the archwire sequence—from round to rectangular in cross-section.

[0023] While using a through-hole offers certain advantages, there is a drawback. When the archwire is positioned in the central slot, the pressure force is distributed approximately equally and uniformly across the contact area of ​​the bracket base with the tooth surface. This is because the bending moment from the archwire above the slot is compensated by an equal, but oppositely directed, bending moment below the slot. The pressure force from the archwire is directed almost perpendicular to the tooth surface.

[0024] A through-hole is located along the length of the slot and offset toward the upper edge of the bracket base. This hole is designed to accommodate an additional archwire of lower rigidity / elasticity. In this case, on a secured bracket (without a main archwire), a compressive pressure directed transversely to the tooth surface is generated in the area above the additional archwire, while a bending moment is generated beneath this hole, directed away from the tooth surface toward the lower part of the bracket. As a result, the connection between the bracket and the tooth at the lower part of the bracket weakens, and the main compressive load shifts toward the upper edge, becoming pointwise or linearly applied to the tooth. This mechanism is evident when using only an additional archwire or a main archwire in combination with an additional archwire.

[0025] The utility model is aimed at achieving a technical result consisting in improving the position of the tooth by equalizing the bending moments when the arches are positioned offset relative to the longitudinal axis of the bracket slot.

[0026] The specified technical result is achieved in that in an orthooptic bracket containing a base with a surface for adjoining the front surface of a patient's tooth, and a housing connected to the base and located above the base, in which an open groove of a rectangular shape in cross-section is made, the longitudinal axis of which is located in the horizontal direction, and which is used to accommodate an elastically deformable orthodontic arch, wherein in the housing above the groove and along it a through channel is made with a cross-section smaller than the cross-section of the groove, for accommodating one additional elastically deformable arch in it, in the housing under the groove and along it a through channel is made with a cross-section smaller than the cross-section of the groove, for accommodating another additional elastically deformable arch in it.

[0027] In this case, the cross-section of each channel can be made square or round in shape.

[0028] For a self-ligating bracket, each channel is made in the form of a single through hole, and for a ligating bracket, each channel is made as a composite of two coaxially located through holes made in the wings.

[0029] In addition, the base can be fixedly connected to the body and made integral with it, or the base can be connected to the body with the possibility of angular deviation from the body in the direction across the groove or along the groove.

[0030] The base can be configured to be fixed thereto on the side of contact with the tooth of the substrate.

[0031] The specified features are essential and are interconnected to form a stable set of essential features sufficient to obtain the required technical result.

[0032] The utility model is explained with specific examples of execution, which, however, are not the only possible ones, but clearly demonstrate the possibility of achieving the required technical result.

[0033] Fig. 1 shows a general view of a self-ligating bracket;

[0034] Fig. 2 - shows the general view of the bracket with wings.

[0035] This utility model proposes a new bracket design, illustrated using an orthodontic self-ligating bracket and a bracket with wings. A bracket or set of brackets (a bracket system) is used to correct malocclusions and crooked teeth by applying gentle pressure to the tooth, which ultimately leads to gradual alignment of the teeth within the dental arch.

[0036] In general, the bracket design includes a base 1 with a working surface facing the tooth surface and attached to this surface. The base may have a backing on the side in contact with the tooth, which is secured to the base surface and used to improve adhesion to the tooth. The working surface of the base must precisely match the shape of the tooth surface at the point of contact. The backing allows for correction of any errors in the shape of the working surface of the base.

[0037] Above the base is the bracket body 2, a monolithic structure containing an open groove 3 of rectangular cross-section with a horizontal longitudinal axis 4. This groove is used to accommodate an elastically deformable orthodontic archwire (not shown). This archwire is made of either steel or a shape-memory alloy (nickel-titanium alloy) and has an arcuate shape. The materials from which the archwire is made have a high degree of elasticity, which, when the archwire's shape changes, attempts to return it to its original position. The archwire's initial shape has a curvature of a smaller radius than the radius of the tooth alignment curve. This archwire is positioned in the groove and acquires a new shape depending on the position of the brackets on the teeth. Deformation of the archwire results in pressure on the brackets, which is transmitted to the teeth.

[0038] The bracket system moves teeth using the force of an archwire made of a special material. The required diameter / cross-sectional dimension and archwire stiffness are determined individually by the orthodontist. The archwire is then placed into the slots of brackets attached to each tooth. The archwire, striving to restore the original shape, constantly exerts force on the tooth, gradually moving it. The doctor secures the brackets to the teeth so that the force of the archwire moves the teeth in the desired direction and corrects the bite, bringing the teeth into a naturally correct and beautiful position. The jawbone is remodeled, and new bone tissue is formed.

[0039] The archwire's position in the slot is well-defined. The slot is created in the central area of ​​the bracket so that the bracket's center of gravity is located in the middle of the slot. When the archwire is applied and the elastic component is exerted, the pressure force on the tooth is almost perpendicular to the tooth surface at the point of contact, and the bending moments above and below the slot are balanced. To achieve this, the archwire profile is selected to minimize angular displacement (up to 5°) when inserted into the slot.

[0040] Base 1 can be connected to body 2 immovably, that is, made integral with the body in the form of a single part, or can be connected to the body with the possibility of angular deviation from the body, that is, hinged.

[0041] In self-ligating braces (Fig. 1), the orthodontic arch is secured with a lock 5. The specific design of the lock is not considered as irrelevant to the essence of the declared model. The issue of the choice of material for the bracket's manufacture is also not addressed.

[0042] Fig. 1 shows an example of a self-ligating bracket with a base 1 rigidly and immovably connected to a housing 2, across which (to be transverse to the tooth) an open groove 3 of a rectangular cross-section is formed, which is closed by a lock 5 of the elastic latch type or another type of latch. A through channel 6 is formed in the housing above and along the groove, with a cross-section smaller than the cross-section of the groove, which is used to accommodate one additional elastically deformable arch. A similar channel 6 is formed under and along the groove, having a cross-section smaller than the cross-section of the groove, for accommodating another additional elastically deformable arch.Other elastically deformable orthodontic arches are understood to be arches of a smaller cross-section and less elasticity, which can be used in the form of corrective arches or independent arches (instead of a centrally located arch in a groove) for the correction of, for example, children's teeth, for which a large amount of pressure is not required.

[0043] For this type of bracket, each channel (6) is designed as a single through-hole, located above and below the groove, respectively. The cross-section of each channel can be either square or round.

[0044] If there is no base archwire in the slot, the bracket is pressed against the tooth using two orthodontic archwires of lower stiffness, each placed in its own channel 6 in the bracket body. These channels are positioned with equal offsets relative to the longitudinal axis of the slot and the center of gravity of the body. In this case, the resulting bending moments from the forces at the points of application of pressure from each archwire are directed toward each other and are balanced in magnitude. This creates an equilibrium state for the bracket, in which all bending moments are neutralized. This results in only one pressure force from each archwire directed toward the tooth surface, acting transversely to that tooth.

[0045] The ligature bracket (Fig. 2) differs from the self-ligating bracket in that it lacks a lock and has projections 7 (wings) on the sides transverse to the groove direction, typically ending in hook-shaped catches. The orthodontic archwire is placed in the groove and secured using a ligature (wire, rubber rings, etc.), which encircles the archwire and fastens to the projections as supports. These projections 7 are arranged in pairs above and below the groove. For this type of bracket, the channels 6 are made composite of two coaxially located through holes (one in each projection of the wings), made in the wings, as shown in Fig. 2. The result is the same as that observed for the self-ligating bracket.

[0046] This utility model is industrially applicable and allows for the balanced positioning of a bracket on a tooth under pressure forces and bending moments when applying a compressive load. This expands treatment options by expanding the torque adjustment device, particularly for the treatment of dental anomalies in children and adolescents.

Claims

1. An orthodontic bracket comprising a base with a surface for contact with the surface of a patient's tooth and a housing with two slots connected to the base and located above it, wherein the first slot is made open, has a rectangular shape in cross-section, with a longitudinal axis located in the horizontal direction, and with the possibility of placing an elastically deformable orthodontic arch in it, and the second slot is made in the form of a through channel, which is located under the first slot and runs along it, wherein the cross-section of the second slot is smaller than the cross-section of the first slot, and with the possibility of placing an additional elastically deformable arch in it, wherein the base is made with the possibility of fixing a substrate to it on the side of contact with the tooth.

2. A bracket according to paragraph 1, characterized in that the cross-section of each channel is made square in shape.

3. The bracket according to item 1, characterized in that the base is fixedly connected to the body.

4. The bracket according to item 1, characterized in that the base is connected to the body with the possibility of angular deviation from the body.

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