Disc displacement without reduction (DDWoR) of the temporomandibular joint is associated with limited mouth opening and arthralgia. In the natural course of the disorder, there is a tendency to progress to degenerative joint diseases. First-line treatment aims to reduce pain and restore joint function. The current study aims to examine the efficacy of an occlusal stabilization splint applied simultaneously with arthrocentesis as first-line treatment in acute and chronic closed-locks.

The present prospective clinical trial included 40 patients who were diagnosed with DDWoR induced chronic (Group 1, n = 23) and acute (Group 2, n = 17) closed-locks. All participants underwent single session arthrocentesis and were applied occlusal stabilization splints. Maximum mouth opening amounts (MMO), Visual analogue scale (VAS), and McGill pain questionnaire (MPQ) scores were evaluated at baseline, on the operation day, and on seven days after the intervention. The obtained data was analyzed with the Wilcoxon signed-rank, Mann-Whitney U, Fisher's exact, Spearman's correlation tests.

According to the baseline data, a significant increase was observed in the amount of MMO in postoperative measurements (p = 0.001 and p < 0.001). A statistically significant decrease in MPQ scores was observed in the postoperative period (p < 0.001 and p < 0.001). While a significant difference was observed between the postoperative VAS scores, the scores of Group 2 were lower (p = 0.018).

Although combined arthrocentesis and occlusal stabilization splint provided significant changes for acute and chronic closed-locks in line with first-line treatment goals, acute closed-lock with arthralgia responded better.

NCT05671549