Orthodontic treatment of temporomandibular joint disorders

Abstract

The invention relates to orthodontics and is intended for detecting temporomandibular joint dysfunction in patients and for treating same using aligners. A digital diagnosis is performed. Functional disorders of the temporomandibular joints (TMJs) are determined on the basis of CBCT, teleradiology, 3D dental scanning, MRI and axiography data. An aligner for positioning the temporomandibular joints and the mandible is modeled in a correct therapeutic position in a digital protocol. An aligner is made in the form of a transparent cap fabricated from a thermoforming sheet based on a multi-layered polyurethane plastic, the aligner having a customized occlusal surface and occlusal onlays with openings for occlusion of the teeth. The techniques used in the method, together with the incorporation of additional elements in the form of occlusal onlays into the structure of the aligner make it possible to correct the position of the entire mandible and the TMJs, precisely maintain the position of the mandible and control the TMJs at all stages of treatment.

Description

[0001] A METHOD OF ORTHODONTIC TREATMENT OF TEMPOROMANDIBULAR JOINT DISORDERS AND AN ALIGNER FOR ITS IMPLEMENTATION

[0002] The group of inventions relates to the field of orthodontics in dentistry and is intended to identify disorders (dysfunctions) of the temporomandibular joints in patients with severe orthodontic pathology using digital diagnostic methods and artificial intelligence, as well as their treatment using aligners.

[0003] The prior art discloses methods for orthodontic treatment of teeth [RU 2761715 C1, application No. 2021143187 dated 25.12.2020, published on 13.12.2021 in Bulletin No. 35; RU 2812389 C1, application No. 2023116246 dated 21.06.2023, published on 30.01.2024 in Bulletin No. 4] using aligners.

[0004] In the first case, a method of orthodontic treatment is proposed that includes a visual examination of the patient, collecting complaints and anamnesis, examining the oral cavity, investigating and ruling out cavities, analyzing panoramic images, taking impressions of the upper and lower jaws, casting plaster models, and planning orthodontic treatment. Impressions are taken using A-silicone Wonflex, and orthodontic treatment planning is performed using 3D modeling of plaster casts, determining the percentage of tooth deviation from their normal position and mathematically planning the process of repositioning the teeth and the wearing time of the aligners.

[0005] In the second method, the final tooth position is determined during the virtual treatment planning stage, and a series of sequentially installed aligners is manufactured to move the teeth. Based on a 3D model of the jaw before treatment and a 3D model of the jaw after treatment, the design of the device is simulated to ensure the desired tooth distalization in the desired direction. During the tooth distalization process, the tooth distalization device and the aligner are installed simultaneously. The tooth distalization device is permanently installed, while each subsequent aligner in the series is installed sequentially. The tooth distalization step caused by the combined action of the aligner and the device is between 0.2 and 1.25 mm.

[0006] Also, open sources of information [https: / / invisalign.ru; https: / / flexiligner.ru; https: / / eurokappa.ru; https: / / 3d-smile.ru; https: / / star-smile.ru] provide information on methods for aligning teeth and correcting malocclusions based on scanning dental impressions to create a 3D image for subsequent use in the manufacture of aligners, including using 3D printing.

[0007] The disadvantages of the above-mentioned technical solutions include inaccurate reproduction of teeth in a physiological occlusion, as well as the lack of correction of the position of the entire mandible and temporomandibular joints (TMJ). The technical result of the proposed invention is to improve the quality of orthodontic treatment and the functioning of the patient's temporomandibular joints.

[0008] The technical result is achieved by the fact that the method of orthodontic treatment of temporomandibular joint disorders includes:

[0009] - digital diagnostics, which consists of determining the functional disorder of the temporomandibular joints in patients with orthodontic pathology based on the obtained data from CBCT, TRG, 3D scanning of teeth, MRI and axiography;

[0010] - modeling of an aligner that positions the temporomandibular joints and the position of the lower jaw in a digital protocol in the correct therapeutic position, while the maximum distance of movement of the condylar processes of the heads of the temporomandibular joints is no more than 1.5 mm, and if movement is necessary over a greater distance, the temporomandibular joints are first moved in the vertical direction and then distracted in the mesio-distal direction at a distance of no more than 1.0 - 1.5 mm;

[0011] - modeling of occlusal pads on premolars in a digital protocol, taking into account the physiological position of the temporomandibular joints;

[0012] - distalization of molars to maintain the position of the lower jaw using aligners during orthodontic treatment;

[0013] - removal of occlusal pads from premolars;

[0014] - modeling of occlusal overlays on molars in a digital protocol to achieve absolute retrocontrol of the position of the lower jaw;

[0015] - final alignment of dental arches with control of tooth root movement.

[0016] The claimed method is carried out as follows.

[0017] The first stage involves determining the functional impairment of the temporomandibular joints in patients with varying degrees of orthodontic pathology severity using digital diagnostic methods. A distinctive feature of the proposed method is the use of a systemic assessment of all structures of the dentofacial complex based on data from cone-beam computed tomography (CBCT), magnetic resonance imaging (MRI) of the TMJ, teleradiography (TRG), axiography, and scanning of the dentition and bite. When diagnosing and planning tooth movement in other treatment methods, there is a disconnect from the individual parameters of the facial skull and TMJ. To visualize tooth movement and approve the case between the doctor and patient, uploading an orthopantomogram (OPG) and TRG in the lateral projection is sufficient. This type of diagnostics allows for a successful assessment of the purely aesthetic appearance of the smile, but does not provide functional diagnostics.Simulation of an aligner (tray) positioning the TMJ and mandible using a digital protocol (the simulation result is shown in Fig. 1). In conventional orthodontic treatment methods, tooth movement is simulated from the habitual occlusion. Analysis of CBCT data reveals a forced position of the mandible in over 70% of cases, most often distal, which can manifest both as overt symptoms (clicking, crunching in the TMJ, pain, and limited mouth opening) and as latent, clinically undetectable structural changes in the TMJ. Thus, competitive alternatives simulate tooth movement from the habitual occlusion rather than from the correct physiological position.

[0018] The present invention proposes the use of a rigid positioning aligner with a completely individual occlusal surface for moving the entire lower jaw and TMJ into a therapeutic position (see Fig.

[0019] 2, where 1 is the aligner). The maximum distance of movement of the condylar processes (heads of the TMJ) does not exceed the safe limits of up to 1.5 mm. If greater movement is necessary, a two-stage movement of the TMJ is performed: first in the vertical direction to eliminate compression injury, followed by distraction in the mesiodistal direction over a distance of no more than 1.0 - 1.5 mm.

[0020] Modeling of occlusal pads in a digital protocol (shown in Fig.

[0021] 3, where 2 are occlusal pads) on the premolars, taking into account the physiological position of the TMJ, to maintain the position of the lower jaw during orthodontic treatment with aligners and distalization of the molars (chewing teeth). Installing occlusal pads after the positioning tray will completely eliminate the problem of the inability to align dental scans in the therapeutic position, since after splint therapy, the occlusion of the dental arches typically differs significantly from the initial state, with occlusion occurring on individual teeth. By digitally modeling and installing premolar pads, it is possible not only to align dental scans and plan the correct tooth movement, but also to maintain the position of the lower jaw and TMJ, and, by disengaging the premolars, significantly accelerate the movement of large molars.This also has important clinical implications for patients and doctors, as this technology can significantly reduce the time required for orthodontic treatment. In cases of secondary premolar loss, occlusal pads can be placed on adjacent teeth.

[0022] Removal of occlusal pads from premolars and digital design of occlusal pads for the posterior teeth (molars) to achieve absolute retroflexion of the mandible. The innovative approach at this stage is that the aligner design has an open occlusal surface in the pad area, and the opposing teeth with the pads in place are in contact with each other, allowing for precise mandibular positioning and temporomandibular joint control at all stages of treatment. The innovative technology of custom-made aligners has completely eliminated the problem of dental "slippage." In patients without functional impairments, this approach allows for effective prophylaxis and prevents the mandible from slipping into a forced position.

[0023] At the final stage of treatment, the final alignment of the teeth is performed, monitoring the movement of the teeth roots and achieving the most aesthetically pleasing smile possible. Importantly, the aesthetics achieved with proper function are much more stable in the long term.

[0024] The developed technology is successfully undergoing clinical trials on patients undergoing treatment at the MYORT clinic network in St. Petersburg. Since November 2017, 1,500 patients have completed orthodontic treatment at MYORT clinics, with 3,600 currently in the active orthodontic treatment phase. The percentage of patients undergoing treatment using the proposed technology is over 80%. Currently, the majority of patients are in the final stages of treatment with the proposed aligners, which will help to collect a large number of completed clinical cases.

[0025] Advantages of the proposed method:

[0026] - when planning treatment, we use not only CBCT, TRG and 3D dental scanning data, but also TMJ MRI and axiography data, which allows for more accurate treatment planning taking into account the individual parameters of the function of the entire dentoalveolar system;

[0027] - diagnostics that allow for a comprehensive and simultaneous analysis of CBCT data, TMJ MRI, axiography, 3D dental scans and facial photographs to create a comprehensive orthodontic treatment plan and visualize tooth movement;

[0028] - allows for reliable comparison of jaw scans in physiological occlusion;

[0029] - provides effective treatment for patients with forced position of the lower jaw or deforming diseases of the TMJ;

[0030] - due to the comprehensive improvement of the function of the entire dental system, a reduction in the retention period is achieved and a more lasting aesthetic result is ensured;

[0031] - reduction in the number of in-person visits to the doctor and the possibility of remote patient care.

[0032] Orthodontic movement of teeth and roots should be performed solely based on the individual parameters of the bone structures of the entire facial skull. Visualization of movement should not be performed separately from the skull, but rather within the entire TMJ-upper and lower jaw-tooth roots-tooth crowns connection. This technology will help avoid numerous iatrogenic complications unrelated to physiological tooth movement and allow for comprehensive dental treatment planning.

[0033] A removable orthodontic device for correcting tooth position is known from the prior art [RU 21 1995 U1, application No. 2022105137 dated February 25, 2022, published June 30, 2022 in Bulletin No. 19]. It is designed as an aligner made of a polymer material shaped like a row of teeth and has at least one working cavity for applying constant pressure to the teeth. The device has through holes through the entire thickness of the row of teeth and blind holes 2 / 3 of the way through the thickness of the row of teeth. The through holes allow air access to the tooth enamel and have diameters from 1 mm to 5 mm. The blind holes have diameters from 1 µm to 5 mm and are partially grouped near the working cavity to change the elasticity of the walls of the working cavity.

[0034] A mouthguard for orthodontic treatment is also known [RU 180855 U1, application no. 2018110351 dated March 23, 2018, published June 28, 2018 in Bulletin No. 19], which is a three-dimensional monolithic product shaped according to the shape of the dentition, taking into account the corrected position of the teeth. The mouthguard is made of two layers, where the first inner layer is made of a rigid thermoplastic plate 0.5 mm thick, and the outer layer is made of a soft one, 1.5 mm thick. Between the layers on the oral side of the product, along the line of the dental arch in the projection of the equator, a nitinol thread is placed with the possibility of reinforcing the product. The thread is pointwise fixed in the projection of at least two teeth.

[0035] A removable orthodontic mouthguard is also known. It is a transparent, thermoformable orthodontic film with a pre-modeled future dental arch shape, including an apical extension in the area of ​​attached gingiva of 1 mm to 3 mm. The mouthguard is made of harmless, transparent thermoplastic and conforms to the surface shape of the teeth in the upper and / or lower dental arch. It can be of varying thickness, hardness, and height depending on the treatment plan and stage. Aligners are used to treat dental anomalies with crowded teeth in the dental arches, where they cover all teeth in the arches. For dentofacial deformities requiring an increase in bite, mouthguards are used that cover all existing teeth down to the last existing tooth on both sides. For mixed dentition deformities, mouthguards cover all existing teeth, including premolars.They are used to treat clusters in the anterior segment of teeth and to guide the distal destruction of premolars in the mixed dentition [BG 3282 U1, application No. 4208 dated December 20, 2018, published October 15, 2019 in Bulletin 10.1]. The technical result of the proposed invention is the development of an aligner that allows for the correction of not only the position of the teeth, but also the position of the entire lower jaw and TMJ, improving the function of the patient's entire dentoalveolar system.

[0036] The technical result is achieved by the fact that the device, which is an aligner in the form of a transparent cap, made from a thermoforming plate based on multilayer polyurethane plastic, with an individual occlusal surface, is additionally equipped with occlusal pads.

[0037] A system of aligners with a unique occlusal (chewing) surface design enables complex orthodontic treatment for patients with TMJ disorders and functional disorders of the masticatory muscles, including those with surgical TMJ pathology, with complete control of the mandible's position throughout the entire treatment period. This is achieved through the phased placement of a rigid positioning aligner at the first stage of treatment to move the mandible to the therapeutic position, followed by the application of individual occlusal pads on the premolars (small chewing teeth), and subsequently on the molars (large chewing teeth) to create retrocontrol and prevent forced displacement of the mandible.

[0038] Fig. 4 (position 1) shows aligners installed on the lower and upper jaws with openings for occlusal closure of the teeth (positions 3 in Fig. 4; positions 2 in Fig. 4 indicate occlusal pads), whereby the preservation of natural occlusion and tubercular closure is achieved, as well as retrocontrol and prevention of forced displacement of the position of the lower jaw.

[0039] The offered aligners allow you to:

[0040] - correct not only the position of the teeth but also the entire lower jaw and TMJ, improving the function of the patient's entire dental system. A key distinguishing feature is the incorporation of additional elements (occlusal pads) into the aligner design, which directly allow for control of the position of the lower jaw, TMJ, and teeth in accordance with individual physiological norms from the correct therapeutic position;

[0041] - accurately maintain the position of the lower jaw and control the TMJ at all stages of treatment, completely eliminate the problem of "sliding" of the dental arches, hold the lower jaw in the desired position and control the TMJ at all stages of treatment due to the design with an open occlusal surface in the area of ​​​​the onlays and contact of the antagonist teeth with the onlays. Due to this separation of the dental arches, the speed of movement of adjacent teeth increases; - ensure ease of installation and removal of aligners due to the use of multilayer polyurethane plastic in the design using Flex & Forcen Grab-Force manufacturing technology. This material has excellent plasticity, while being highly flexible and ensures more effective tooth movement and predictable results;

[0042] - to treat patients with TMJ diseases in the acute stage, as well as patients who want to improve the aesthetics and functioning of the lower jaw.

Claims

Invention formula 1. A method of orthodontic treatment of temporomandibular joint disorders, including: - digital diagnostics, which consists of determining the functional disorder of the temporomandibular joints in patients with orthodontic pathology based on the obtained data from CBCT, TRG, 3D scanning of teeth, MRI and axiography; - modeling of an aligner that positions the temporomandibular joints and the position of the lower jaw in a digital protocol in the correct therapeutic position, followed by the production of an aligner in the form of a transparent cap made of a thermoforming plate based on multilayer polyurethane plastic with an individual occlusal surface and occlusal pads with holes for occlusal closure of the teeth, while the maximum distance of movement of the heads of the condylar processes of the temporomandibular joints is no more than 1.5 mm, and if movement is necessary over a greater distance, the heads of the temporomandibular joints are moved first in the vertical direction and then distraction is performed in the mesio-distal direction at a distance of no more than 1.0 - 1.5 mm; - modeling of occlusal pads on premolars in a digital protocol, taking into account the physiological position of the temporomandibular joints; - distalization of molars to maintain the position of the lower jaw using aligners during orthodontic treatment; - removal of occlusal pads from premolars; - modeling of occlusal overlays on molars in a digital protocol to achieve absolute retrocontrol of the position of the lower jaw; - final alignment of dental arches with control of tooth root movement.

2. An aligner for implementing the method according to paragraph 1, made in the form of a transparent cap made from a thermoforming plate based on multilayer polyurethane plastic, with an individual occlusal surface, and occlusal pads with openings for occlusal closure of the teeth.

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