The role of intercuspal occlusal relationships in temporomandibular disorders: a review.

The purpose of this review is to highlight consensus in past research on the role of intercuspal occlusal factors in the pathophysiology of temporomandibular disorders. The occlusal intercuspal relationships considered are skeletal anterior open bite, overbite, overjet, symmetry of contacts in the retruded contact position (RCP), crossbite, and posterior occlusal support. Skeletal anterior open bite, reduced overbite, and increased overjet are associated with osteoarthritic TMJ patients, but lack specificity for defining patient populations per se. There is no evidence that overbite or overjet plays a role in the pathophysiology of nonarthritic disorders. A combination of unilateral RCP with an absence of a clinically apparent RCP-ICP (intercuspal position) slide may encourage TMJ disc displacement, but unilateral RCP per se was not associated with TMJ diagnoses. Crossbite does not seem to provoke TMJ symptoms or disease. Lost molar support may be associated with osteoarthrosis presence and severity, but studies have not yet been distinguished for age effects. Where appropriate, implications for clinical practice are drawn.