Bilateral condylar movement patterns in adult subjects.

The purpose of this study was to determine if there was a difference between the temporomandibular condylar movement patterns of a symptomatic adult population and those of an asymptomatic adult population. Thirty-five volunteers who were not seeking treatment for TMD underwent two different assessments for TMD signs and symptoms: (1) a self-administered questionnaire and (2) a clinical examination. Based on the information obtained from the questionnaires, subjects were divided into "reported-symptomatic" and "reported-asymptomatic" groups. Based on the investigator's clinically evaluation of the same subjects, subjects were divided into "clinically symptomatic" and "clinically asymptomatic" groups. To compare condylar movement patterns, both groups of subjects then had their mandibular border condylar movements measured bilaterally using a sagittal recording device during maximum opening, maximum protrusion, and maximum left and right excursion movements. The patterns were separated into two broad groups, "symmetric" and "asymmetric." Symmetric gliding movements were defined as uninterrupted bilaterally mirror-like patterns of each condyle with a difference between left and right total length excursion not exceeding 2 mm during opening in the sagittal plane or horizontal plane. Our results show that 63% of the subjects who reported clinically asymptomatic for TMD demonstrated asymmetric condylar movements. However, 100% of the patients (n = 5) who reported clinically symptomatic for TMD exhibited asymmetric condylar movements. This finding suggests that, while a very high percentage of TMD subjects will have asymmetric condylar movements, condylar movements alone are not necessarily diagnostic of TMD, and the sagittal recording device may alert the clinician to abnormal movements.