Administration of botulinum toxin type A (BTX-A) 10 mouse units (MU) injection in the masseter muscle relieved muscle spasms and pain linked with nocturnal bruxism for almost three months before the symptoms progressively relapsed, as deciphered from a research article in Cureus Journal of Medical Science. To study the effect of different dosages of Botox therapy for nocturnal bruxism, Zaed Ghassan Shehri et al. determined whether masseter (one of the muscles of mastication) muscular injections of 10 MU of BTX-A could lessen nocturnal bruxism.

Overall, 22 patients with pain in the masseter muscle and sensitivity of the teeth due to its wear as a result of nocturnal bruxism were included in this randomized controlled clinical trial. They were stratified into two groups, namely Botox (BO) group and the placebo (PL) group with 11 patients each. Efficacy parameters were: Pain and muscle activity assessed via visual analogue scale (VAS) and electromyography (EMG).

Twenty patients entered data estimation as 1 patient each from both groups withdrew from the study. Statistically significant differences were registered for perceived pain values and EMG recorded values between the groups before and after the administration of the injection. The variations in the perceived pain values over time were statistically significant in the BO group.

Although the pain levels were considerably alleviated at 2 weeks, 1 month, and 3 months after the injection, they again significantly increased at the 4th- and 6th months. Botulinum toxin injection seems to be beneficial for sleep-related bruxism.