Mandibular Range of Movement and Pain Intensity in Patients with Anterior Disc Displacement without Reduction

Temporomandibular disorders (TMD) are the most common source of orofacial pain of a non-dental origin. The study was performed to investigate the therapeutic effect of the conventional occlusal splint therapy and the physical therapy. The hypothesis tested was that the simultaneous use of occlusal splint and physical therapy is an effective method for treatment of anterior disc displacement without reduction.

Twelve patients (mean age =30.5 y) with anterior disc displacement without reduction (according to RDC/TMD and confirmed by magnetic resonance imaging) were randomly allocated into 2 groups: 6 received stabilization splint (SS) and 6 received both physical therapy and stabilization splint (SS&PT). Treatment outcomes included pain-free opening (MCO), maximum assisted opening (MAO), path of mouth opening and pain as reported on visual analogue scale (VAS).

At baseline of treatment there were no significant differences among the groups for VAS scores, as well as for the range of mandibular movement. VAS scores improved significantly over time for the SS&PT group (F=28.964, p=0.0001, effect size =0.853) and SS group (F=8.794, p=0.001, effect size =0.638). The range of mouth opening improved significantly only in the SS&PT group (MCO: F=20.971, p=0.006; MAO: F=24.014, p=0.004) (Figure 2). Changes in path of mouth opening differ significantly between the groups (p=0.040). Only 1 patient in SS&PT group still presented deviations in mouth opening after completed therapy while in the SS group deviations were present in 5 patients after completed therapy.

This limited study gave evidence that during the treatment period lasting for 6 months, the simultaneous use of stabilization splint and physical therapy was more efficient in reducing deviations and improving range of mouth opening than the stabilization splint used alone. Both treatment options were efficient in reducing pain in patients with anterior disc displacement without reduction. Despite of objectively diagnosed disruption of temporomandibular joint anatomy, physiological function was regained.