Botulinum toxin in the management of myofascial pain associated with temporomandibular dysfunction.

[INTRODUCTION] Critical evidence on the therapeutic efficacy of botulinum toxins (BTX) is still lacking for most pain conditions. The aim of this review was to evaluate the therapeutic efficacy of BTX in the management of temporomandibular myofascial pain.

[MATERIALS AND METHODS] Electronic databases PubMed, EMBASE, Scopus, Web of Science, and gray literature were searched for randomized clinical trials until February 2018 to answer a focused question "What is the effectiveness of botulinum toxin in the management of temporomandibular myofascial pain?" Two independent reviewers performed the study selection according to eligibility criteria.

[RESULTS] A total of seven studies that met the eligibility criteria were included. Two studies showed a significant improvement in temporomandibular myofascial pain, and one study showed equal efficacy of BTX in comparison with facial manipulation, while the remaining studies did not report any significant difference between BTX and control group. Due to heterogeneity in the methodology and outcome assessment, a meta-analysis and recalculation of risk could not be performed.

[CONCLUSION] Based on our findings, the therapeutic efficacy of BTX was unclear. Randomized controlled trials with better methodological criteria need to be carried out to evaluate the real effectiveness of BTX.