Botulinum Toxin Versus Dextrose Prolotherapy: Which is More Effective for Temporomandibular Joint Subluxation? A Randomized Clinical Trial

Botulinum toxin type A (BTX-A) therapy or dextrose prolotherapy (DP) has been used to treat temporomandibular joint (TMJ) disorders. However, the superiority of one method over the other has not been studied in patients with TMJ subluxation. Therefore, this study aims to answer the following clinical question: among patients with TMJ subluxation, do those undergoing BTX-A injection into lateral pterygoid muscles, compared to those undergoing intra- and periarticular DP injections, have better outcomes in terms of locking episodes and patient satisfaction? A randomized clinical trial was implemented in adult patients with TMJ subluxation. The sample was composed of patients with TMJ subluxation with painful open-locking during wide mouth opening and/or yawning at baseline. The subjects were treated randomly with one of two treatment techniques with equal numbers as follows: one-session BTX-A injection into lateral pterygoid muscles (BTX-A group) or three sessions of dextrose injections around TMJ (prolotherapy group). The predictor variable was the treatment technique (BTX-A or prolotherapy injections). The primary outcome variable was the frequency of locking episodes. The secondary outcome variable was patient satisfaction. The primary outcome variable was recorded at baseline and 8-12 months following the injections. The secondary outcome variable was recorded only 8-12 months following the injections. Descriptive and bivariate statistics were computed. The data were analyzed with the Wilcoxon and Mann-Whitney U tests. The baseline sample was composed of 30 patients with TMJ subluxation. However, the follow-up sample comprised 25 subjects: 11 (9 females, 2 males; 25.64 years) in the BTX-A group and 14 (10 females, 4 males; 32.37 years) in the prolotherapy group. Locking episodes decreased significantly in the two groups with no significant difference (P .05). Patient satisfaction showed no significant difference between the groups (P > .05). These findings suggested that BTX-A injection is no more effective than DP for any outcome variables of TMJ subluxation assessed.