Incobotulinum toxin type A for treatment of chronic myofascial pain.

PURPOSE: This study assessed the effectiveness of incobotulinum toxin type A (IBTx) for chronic myofascial pain affecting the masseter and temporal muscles. METHODS: Twenty two patients who received a diagnosis of chronic masseter and temporalis myofascial pain were evaluated by using a visual analog pain scale (VAS), digital pressure algometry, and the SF-36 Health Survey at baseline (T0), before IBTx injection. Patients were again evaluated at 2 months (T1) and 7 months (T2) after IBTx injection. RESULTS: VAS scores for pain significantly differed (P = 0.029, Friedman test). Post-hoc tests showed a significant reduction in pain at 2 months (T0-T1) and 7 months (T0-T2) (P = 0.011 and P = 0.028, respectively; Wilcoxon test) but not between 2 and 7 months (P = 0.676; Wilcoxon test). There was no significant difference in pressure algometry values (P = 0.385, Friedman test). Quality of life (QOL) assessment showed a significant difference (P = 0.002, Friedman test). Post-hoc tests showed a significant improvement in QOLat 2 months, but no significant difference at 7 months (P = 0.004 and P = 0.260, Wilcoxon test). CONCLUSION: IBTx injection resulted in safe, effective short-term pain relief for patients with chronic facial pain affecting the masseter and temporalis muscles.

Efficacy of botulinum toxin therapy in treatment of myofascial pain.

The present study aimed to assess the efficacy of using botulinum toxin (BTX) in temporomandibular joint disorders, particularly pertaining to myofascial pain from masseter and temporal muscles. The study included 11 patients who were diagnosed with masseter and temporalis myofascial pain. Visual analog scale for pain and pressure algometry were conducted initially, after 1 month of conservative therapy (control group), and after 1 month of BTX type A injections (study group). Data were statistically analyzed (analysis of variance and Wilcoxon's test) to determine intergroup differences. Both conservative therapy and BTX injections showed reduction in pain scores and increase in pain threshold compared with baseline, and statistically significant differences were noted between both groups. Thus, BTX injections appear to be effective in management of chronic myofascial pain targeting masseter and temporalis muscles.