Botulinum toxin a as a treatment for temporomandibular disorders: A systematic review

Background/Aim: This systematic review assesses the efficacy of botulinum toxin (BTX) injections in managing temporomandibular disorders (TMD), myofascial pain, and bruxism. Material and Methods: Following PRISMA guidelines, a literature search was conducted using PubMed and Google Scholar, focusing on clinical studies from 2000 to 2024 involving intramuscular BTX administration for TMD in adults. Inclusion criteria targeted clinical studies, while reviews, case reports, and laboratory studies were excluded. A total of 47 clinical studies were reviewed, and outcomes were summarized and analyzed. Results: BTX injections primarily targeted the masseter and temporalis muscles, with administered doses ranging from 10 to 75 IU per muscle. BTX injections demonstrated significant efficacy in reducing pain (up to 91%), improving mandibular mobility and lateral jaw movements. Bruxism episodes were notably reduced by up to 87%, often accompanied by improved sleep quality. Adverse effects were generally mild, with transient muscle atrophy resolving within three months. Discussion: The findings of this review consistently demonstrate the efficacy of BTX in alleviating pain and reducing bruxism associated with TMD. A clear dose-response relationship and temporal effect were observed, with symptom improvement peaking at approximately six months post-injection. However, the heterogeneity among included studies, particularly regarding patient populations, treatment protocols, and outcome measures, limited the ability to conduct direct comparisons and meta-analysis. Conclusions: The collective evidence suggests that BTX may serve as a valuable adjunct to conventional TMD management, offering significant pain relief and improved quality of life for affected individuals. To optimize clinical practice, further well-designed studies are needed to establish standardized treatment protocols and identify patient subgroups most likely to benefit from BTX therapy.