Psychological distress and diagnostic subgroups of temporomandibular disorder patients.

This study examined the nature and extent of psychological differences among diagnostic subgroups of temporomandibular disorder (TMD) patients. Three subgroups were identified and labeled as: (1) primary myalgia, (2) primary temporomandibular joint (TMJ) problems, or (3) combination myalgia and TMJ problems. Patients' (n = 112) levels of pain and distress were measured using a VAS pain scale, the McGill Pain Questionnaire, the Beck Depression Inventory, the State-Trait Anxiety Scale and the MMPI.