Orthopedic Treatment

While TMJ disorders are self-limiting, there is no need to wait for time or natural adaptation, because the symptoms can be eliminated in both long and short term by orthopedic treatments that address the symptom generating process, the sustaining factors that make it chronic, and the dysharmonious jawbone growth that continually produces the stresses and strains that require adaptation. The conceptual basis for mandibular orthopedics is explained in BITES: ORTHOPEDIC PERSPECTIVES.

Most of the oral appliances used today for treatment of TMJ disorders simply provide a stable bite with average canine and anterior guidance at an increased vertical dimension when the mandible is in a relatively unstrained location at the back end of its normal range of motion. Thus their primary orthopedic effect is just providing a stable and raised posterior bite platform. The increased bite stability can relieve jaw muscle tension by reducing the hypervigiliance that is found in all muscles crossing unstable joints, which is one reason these appliances are often helpful in symptom relief. The raised vertical dimension can stretch tight jaw muscles, which is a second reason these appliances are often helpful in symptom relief. However, much more effective long-term and short-term treatment can be obtained by also incorporating mandibular and facial orthopedics, because TMJ disorders are musculo-skeletal disorders. Our orthopedic treatments include:

Joint protective stabilization appliances
Joint protective telescopic appliances
Pivoting for unilateral condylar distraction
Disk recapturing
Flat bite plate (deprogramming) appliances
Rubber bite cushion appliances
Bite restoring appliances
Bite stabilization
Functional orthodontics

JOINT PROTECTIVE STABILIZATION APPLIANCES are used to provide a bite table that prevents the condyles from access to the inflamed retrodiskal tissues in TMJs with dislocated disks. Steep anti-retrusive ramps are used to protect severely inflamed TMJs, and shallow anti-retrusive ramps are used when there is less need for joint protection and more need for muscle rehabilitation.

JOINT PROTECTIVE TELESCOPIC (HERBST) APPLIANCES are even more effective for protecting damaged TMJs than stabilization appliances, because they prevent the mandible from retruding into the bruised retrodiskal tissues, even when the mouth is partly open. For additional orthopedic effects, these appliances can also include a full arch bite surface, a front flat plate bite surface, dual block mechanics (opposing inclines that engage), laterally directed inclines to correct the mandibular midline, or a unilateral pivot to distract a condyle from an inflamed TMJ. However, the Herbst hardware commonly used today was designed more than a century ago for orthodontic bite jumping in children, and adults find it uncomfortable and restrictive; therefore Dr. Summer has redesigned it with a lower profile, a free lateral range of movement, and micro-adjustability without tools, as described with photos in MULTI-LEVEL ORAL APPLIANCE TREATMENT OF SLEEP APNEA.

PIVOTING can be added to any type of joint protective appliance to provide quick relief for an acutely inflamed TMJ by distracting the affected condyle. The pivot must be unilateral and located behind the first molar, where the center of force of the jaw closing muscles is located. A correctly placed pivot allows the patient to bite forcefully without experiencing the pain produced by biting forcefully on the natural teeth. However pivoting can place a lot of pressure on a single molar, therefore it is only used as a temporary short term intervention.

UPPER FRONT FLAT PLATE APPLIANCES, also know as anterior deprogrammers, are employed to reduce overbite and treat tight jaw muscles after the TMJs have fully healed and thus no longer need protection. The plane of the front flat bite table is parallel with the pull of superior lateral pterygoid muscles, which facilitates their positioning of the mandible. From the first night they are worn, these appliances reduce the strength of nocturnal bruxism by about half. Over the course of weeks, they deprogram the jaw muscles in order to reveal an unstrained mandibular closing trajectory that can be used to evaluate the health of the bite. Over the course of years, they redirect the large compressive forces of nocturnal bruxism onto the front teeth in order to gradually intrude them and make them shorter while allowing extrusion of the back teeth that makes them taller, resulting in a slow steady reduction of the overbite. A temporary chairside version is a good diagnostic tool.

FULL ARCH FLAT PLATE APPLIANCES, combine the functions of flat plate appliances and stabilization appliances. They are generally used when the patient has little or no overbite, and an upper front flat plate could produce a negative overbite.

RUBBER BITE CUSHION APPLIANCES are simple tight fitting rubber shells that are used during the daytime to provide a stable cushion for the mandible in people who have unstable bite tables or to relieve jarring bite impacts in people who have neuromuscular systems that have been sensitized by chronic pain. Rubber appliances are often counter-productive when worn during sleep, because the rubbery feel evokes increased chewing activity, usually coupled with dreams of eating.

BITE STABILIZATION may be necessary to give the mandible a consistent home base that enables the TMJs to acquire the same goodness of fit found between the articulating components of all healthy joints in their fully seated (braced) positions. Joint stability is at the heart of orthopedics, and the bite functions as a joint between the jawbones. If the bite is unstable, the jaw muscles become hypervigilant and increase their resting tonus. In many TMJ disorder patients, the bite has been destabilized by disk dislocation or degenerative remodeling, both of which shorten the affected condyle, or by TMJ swelling which effectively lengthens the affected condyle. Sometimes the bite keeps changing slightly due to periodic shifting between these conditions. After the inflammation is resolved, the bite can be restabilized by reducing high areas, building up low areas, and/or moving teeth. The choice depends on face height and dental needs.

BITE RESTORING is often needed in patients who have worn an oral appliance for long enough to make the teeth of the opposing arch shift until they fit the surface of the appliance rather than the natural teeth. When they remove their appliance, these patients have no bite. In these cases, we first establish a proposed new bite on a provisional basis using tight fitting unobtrusive unilateral removable bite restoring appliances that don’t impair speech and can be worn all day, including while eating. The new bite provides widespread support for the mandible within a small bracing area (about 4 square mm), surrounded by slopes that provide support for the mandible in all directions of movement away from that small bracing area. The occlusal contours should not restrict the mandibular range of motion preferred by the jaw muscles or "guide" the mandible. If the occlusion established in resin is shallow enough to allow strong functional forces, they will refine the occlusion more accurately than any techniques our equipment allows. After that new bite has proven effective and comfortable, it is transferred to the teeth by bonded composite resin onlays for further refinement and testing prior to finalizing it in gold or porcelain, usually performed by the patient’s general dentist with Dr. Summer providing any support required. If finishing needs to be delayed for dental or financial reasons, the unilateral removeable bite restoring appliances can be reinforced with stainless steel mesh.

ORTHOPEDIC DISK RECAPTURE may be needed for patients who find that nothing provides relief as long as a TMJ disk keeps shifting in and out of its proper location in the TMJ; but successfully completing the treatment requires permanently changing the bite, which can involve expensive dental work. Many of the early attempts at orthopedic disk recapture in the 1980's and 1990's failed, because the treating dentists did not understand how to reconstruct a new bite that maintained the correction. Frequently the teeth need contours that are slightly different from those seen on natural teeth, requiring extensive communication with the dental laboratory. To help identify anatomical features affecting the prognosis for disk recapture, Dr. Summer collaborated with the leading TMJ radiologist to perform and publish a study using before and after MRI on 119 joints undergoing this treatment. It's now clear that disks can be recaptured if the right anatomical factors are present and the bite is finalized correctly, but most patients do not need such extensive treatment.

FUNCTIONAL ORTHODONTICS, using removeable oral appliances, often has advantages over esthetic orthodontics (braces and invisalign) for treating and preventing TMJ disorders, because it can hold the mandible in an orthopedically ideal position while moving the teeth into positions which can support it there, while esthetic orthodontics retracts the mandible to facilitate aligning the teeth into parallel arch forms. Functional orthodontic appliances can also stimulate jaw muscle development by protecting damaged TMJs while giving the jaw muscles an ideal exercise template to work out against. Palatal expansion can be added to enlarge the nasal airway or increase the space available for crowded or newly erupting teeth.