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

This review highlights the consensus existing in past research on the role of functional occlusal factors in the pathophysiology of temporomandibular disorders (TMD). The functional occlusal relationships considered are balancing and working occlusal contacts, length and symmetry of retruded contact position-intercuspal position (RCP-ICP) slides, occlusal guidance patterns, parafunction, and dental attrition. Controlled studies fail to demonstrate any association between occlusal interferences and TMD signs or symptoms. Temporomandibular joint condylar autorepositioning secondary to intracapsular arthrosis is associated with larger and asymmetric RCP-ICP slides. Other TMD conditions are not associated with any slide length or asymmetries. Occlusal guidance patterns are not associated with TMD symptom provocation or, conversely, health. Parafunction appears to be universal and is not associated with TMD development or symptomatology in healthy individuals. Furthermore, parafunction is not provoked by longstanding, naturally occurring occlusal variations. Dental attrition is not associated with TMD, and any observed increased attrition in osteoarthrosis patients is likely the result of age effects and occlusal alterations secondary to condylar positional changes.