Orthodontic relapse can occur in patients with temporomandibular joint (TMJ) pathologies despite sophisticated treatment. The TMJs are the foundation for jaw position, function, and occlusion. The progressive development of an anterior open bite has commonly been attributed to orthodontic relapse or parafunctional habits such as tongue thrust. However, a common etiology for the progressive development of an anterior open bite is TMJ pathology.
Retruded Mandible
TMJ pathology can adversely affect orthodontic treatment stability, as seen in the 18-year-old female in Figure 1 A–C and G. Her second phase of orthodontic treatment occurred from the age of 12 to 14 with a good occlusion result, but within 6 months after orthodontics she had developed a Class II anterior open bite, TMJ pain, headaches, popping in her TMJs, and difficulty eating. She was placed in a bite splint for 3 years without resolution of her pain and jaw dysfunction prior to referral to the author for definitive treatment.
This is a classic case of Adolescent Internal Condylar Resorption (AICR), one of the most common TMJ conditions seen in teenage females in orthodontic practices. (This conditions occurs in an 8:1 female-to-male ratio). This hormonally mediated condition is initiated as the adolescent enters the pubertal growth phase (between 11 and 15 years). The discs become anteriorly displaced and the condylar heads resorb, with slow but progressive retrusion of the mandible creating a Class II occlusal relation and an anterior open bite. Of these patients with AICR, 25% are asymptomatic relative to pain and joint noises, but still have the displaced discs and condylar resorption. All patients have high occlusal plane angulation with a retruded mandibular facial morphology.
Our treatment protocol has proven to eliminate this TMJ pathology and allow optimal correction of the associated dentofacial deformity. The protocol includes: 1) Remove the reactive tissues surrounding the condyle; 2) reposition and stabilize the disc to the condyle with a Mitek anchor and artificial ligaments; and 3) perform the indicated orthognathic surgery.
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