CLINICAL EXAMINATION FINDINGS OF TEMPOROMANDIBULAR DISORDER PATIENTS - A FACTOR-ANALYTIC STUDY

To assess the latent factor structure of clinical examination findings obtained from temporomandibular disorder patients, exploratory factor analysis was used to examine the relationships of a large number of v ariables obtained from a clinical examination to a smaller number of l atent variables, or factors. Two independent samples of patients-an in itial sample that consisted of 330 patients who complained of facial p ain and a validation sam pie of 161 additional patients-were examined to determine whether the factor structure was reliable. A principal ax is factor analysis with varimax rotation was used for both sets of dat a. The factor structure for the two samples was consistent between the two sets of data. Results identified two muscle pain factors tan ''in traoral muscle'' factor and an ''extraoral muscle'' factor), two unila teral jaw pain factors, and two factors that concern joint noise (clic king and crepitus). The implications of these findings for the current nosologic systems for temporomandibular disorders are discussed.