Evaluation of botulinum toxin injection in masticatory muscles for managing temporomandibular disorders pain.

Objective: To evaluate injection of botulinum toxin in masseter and temporalis muscles as a treatment modality for temporomandibular disorders pain. Subjects and Methods: A total of 14 patients diagnosed with TMD were selected from the Out-Patient Clinic of the Oral Surgery Department at Faculty of Dental Medicine, Cairo-boys, Al-Azhar University, Egypt. Study included patients with myofascial pain, pain associated with disc displacement with reduction, pain associated with hypermobility of the T.M.J. Patients with unilateral or bilateral disease were accepted equally. They were divided into 2 groups study group which received the botulinum toxin injections and control group which received 0.9% saline solution. Patients had 4 follow ups in total first at the injection session then after 1 month, after 3 months and after 6 months post injection. 4 parameters were recorded Pains scores on the VAS, vertical mouth opening, Tenderness to palpation and Masseter muscle activity using EMG. Results: Results revealed that, there was statistically a significantly lower pain values and increased mouth opening reported after 6 months of botulinum toxin injection. Conclusion: the injection of botulinum toxin is effective in decreasing pain and increasing mouth opening in patient diagnosed with TMDs.