Role of condylar position in TMJ dysfunction-pain syndrome.

TLDR: It can be concluded that condylar position in the fossae is a significant factor in TMJ dysfunction-pain syndrome, and even in asymptomatic patients one third can be retruded, TMJ radiography and occlusal evaluation are indicated in almost all patients.

Abstract: TMJ dysfunction-pain syndrome is multicausal, and each patient has an individual "TMJ dysfunction profile." Stress has been shown to be a correlated factor as well as occlusion. Strong stress etiology and a placebo effect have been reported in MPD. It was emphasized, however, that MPD does not involve pain or pathology of the TMJ itself, by definition , and that research (for MPD) is not valid for TMJ dysfunction-pain syndrome which does involve the joint itself, by definition . Condylar position in the fossae of 116 patients was reported, 55 acute TMJ dysfunction-pain and 61 general practice controls. The main findings were that the incidence of condylar retrusion in the acute TMJ patients was 70.9% and condylar concentricity (in the middle of the fossae) was only 3.6%. In the general practice control group, the incidence of condylar retrusion was 36% and condylar concentricity 23%. The incidence of condylar retrusion in the acute TMJ group was twice that in the control group. Conversely, the incidence of condylar concentricity in the general practice control group was 6.4 times the occurrence in the acute TMJ group. It can be concluded that condylar position in the fossae is a significant factor in TMJ dysfunction-pain syndrome. Furthermore, condylar retrusion occurs much more frequently (71%) than other types of displacement in acute TMJ dysfunction-pain. Condylar retrusion also occurs with enough frequency in the general practice control (36%) to indicate that the "classical" retruded mandibular position of centric relation does not necessarily orient the condyles correctly in the fossae, as is commonly thought. The fact that condylar concentricity (middle of the fossae) was 6.4 times more prevalent in the general practice control group, together with previously reported evidence, confirms (that it is the optimum position in the glenoid fossae. Since the condylar position in the fossae is significant, and even in asymptomatic patients one third can be retruded, TMJ radiography and occlusal evaluation are indicated in almost all patients.