Trauma history in diagnostic groups of temporomandibular disorders.

Trauma history was studied for association with disease among six diagnostic subgroups of 230 patients with temporomandibular disorder (TMD) from a private practice setting with (1) disk displacement (DD) with reduction, (2) DD without reduction, (3) osteoarthrosis (OA) with prior derangement history, (4) primary OA, (5) myalgia only, and (6) subluxation only. Except for subluxation (29%), trauma history typified TMD patient groups 1 to 5 (63%, 79%, 44%, 53%, 54%) (p less than 0.001) compared with 13% and 18% of asymptomatic (n = 61) and symptomatic (n = 161) student control subjects, and 11% of general dental patients (n = 150). TMD groups 2 and 3 differed significantly (p less than 0.05). The high prevalence of trauma in the myalgia-only group complicates the concept of myofascial pain-dysfunction syndrome as solely a stress or centrally mediated disorder. DD without reduction (43%) and with reduction (38%) had the highest prevalences of motor vehicle accident trauma, myalgia and OA groups had less, and subluxation-only cases had none. On the other hand, patients with DD without reduction were also the only group to report multiple trauma (29%), suggesting that although specific traumatic events may seem to precipitate clinical symptoms, they may not always have initiated the problem. Trauma may be both an important cumulative and precipitating event in TMDs.