Efficacy of botulinum toxin type a in the targeted treatment of sleep bruxism: a double-blind, randomised, placebo-controlled, cross-over study

Belinda Cruse; Thanuja Dharmadasa; Elise White; Callum Hollis; Andrew Evans; Sifat Sharmin; Tomas Kalincik; Lynette Kiers

doi:10.1136/bmjno-2022-000328

Efficacy of botulinum toxin type a in the targeted treatment of sleep bruxism: a double-blind, randomised, placebo-controlled, cross-over study

BMJ Neurol Open. 2022 Sep 5;4(2):e000328. doi: 10.1136/bmjno-2022-000328. eCollection 2022.

Authors

Belinda Cruse^{1

2}, Thanuja Dharmadasa¹, Elise White¹, Callum Hollis¹, Andrew Evans^{1

2}, Sifat Sharmin², Tomas Kalincik^{1

2}, Lynette Kiers^{1

2}

Affiliations

¹ Neurology, The Royal Melbourne Hospital City Campus, Parkville, Victoria, Australia.
² Department of Medicine (RMH), The University of Melbourne Faculty of Medicine Dentistry and Health Sciences, Melbourne, Victoria, Australia.

Abstract

Background: Intramuscular injections of botulinum toxin A (BTX-A) have been used in the treatment of sleep bruxism (SB) however controlled trials are limited and the optimal injection strategy and dose is not known.

Methods: This double-blind, randomised, placebo-controlled, cross-over study evaluated the efficacy and safety of BTX-A in participants with SB. Average bruxism events per hour of sleep (Bruxism Index, BI) was calculated using surface electromyography. Participants with BI >5 were included and randomised by order of injection (active or placebo with the opposite 20 weeks later) and into one of three differing treatment groups: bilateral masseter (60 units(U)), bilateral masseter and temporalis (90U) and bilateral masseter, temporalis and medial pterygoid muscles (120U). Change in BI and subjective measures of headache, pain, and bruxism at 4 and 12 weeks was calculated following intervention, and differences between treatment groups analysed.

Results: 41 participants were recruited, 35 randomised and data from 22 participants (14 female) were analysed. BI was significantly lower at 4 weeks after active treatment when compared with placebo (mean=-1.66, p=0.003), not sustained at 12 weeks. The difference was greater with higher doses injected and among those with greater baseline BI. There was no difference in subjective measures at any time point. Five participants injected had mild, transient side effects.

Discussion: Targeted BTX-A injection is a safe and effective treatment for SB. A greater benefit may be achieved by administering BTX-A into more muscles and at higher total doses and among those with higher baseline BI.

Trial registration number: ACTRN12618001430224.

Keywords: BOTULINUM TOXIN; SLEEP DISORDERS.