Bruxism had been defined as, a repetitive masticatory muscle activity (RMMA) characterised by clenching or grinding of the teeth and/or by bracing or thrusting of the mandible. It can occur during wakefulness or during sleep. The potential impact of bruxism on the stomatognathic system is of interest to dentists but it is also of interest to clinicians other field including sleep medicine, neurology and psychology. Management involved combination of oral appliances, counselling/ behavioural strategies and centrally acting drugs, with a common target being muscle relaxation.
The aim of this review was to assesses the effects of botulinum toxin (BoNT-A) injections in the management of bruxism.
Methods
Searches were conducted in the PubMed, Scopus, Web of Science, Embase, Cochrane, Scielo and Lilacs databases from 1980. All types of clinical studies including randomized, prospective and before–after design conducted in humans assessing the effects of (BoNT-A) injections on bruxism were considered.
Three reviewers independently selected studies. Study quality of randomised controlled trials( RCTs) was assessed using the Cochrane risk of bias tool and nonrandomised studies using the Critical Appraisal Skill Programme Before–After Study Checklist. A narrative summary was presented.
Results
- 5 studies (3 RCTs, 2 before and after studies) involving a total of 188 patients were included.
- All 5 studies investigated sleep bruxism.
- The quality of the RCTs was considered to be low to moderate and the before and after studies moderate.
- Only 2 studies used polysomnography/electromyography for sleep bruxism diagnosis, All studies using subjective evaluations for pain and jaw stiffness showed positive results for the BoNT-A treatment.
- 2 studies using objective evaluations did not demonstrate any reduction in bruxism episodes, but a decrease in the intensity of muscles contractions.
Conclusions
The authors concluded
Within the limitations of this review, botulinum toxin represents a possible management option for purported sleep bruxism consequences, minimizing symptoms and reducing the intensity of contractions for RMMA, rather than for SB itself. Notwithstanding that, further studies are needed to refine the available knowledge on the topic
Comments
A broad range of databases has been searched to identify potential studies for inclusion in this review, although studies have been restricted to those published in English. Only 3 small RCTs of low quality are available to assess the effectiveness of BoNT-A treatment for bruxism. The included studies also had heterogeneous protocols. A 2013 review assessing any treatment for sleep bruxism by Manfredini et al (Dental Elf 30th Jun 2015) one of the authors on this current review included 12 RCTs but again not finding enough evidence to recommend the best treatment approaches. While the authors suggest that this may be a potential management option for sleep bruxism more high quality studies are needed. These studies should also include adverse effects of BoNT-A treatment for as noted in the discussion as bone loss and decreased masticatory performance have been reported even after a single injection.
Links
Primary paper
De la Torre Canales G, Câmara-Souza MB, do Amaral CF, Garcia RC, Manfredini D. Is there enough evidence to use botulinum toxin injections for bruxism management? A systematic literature review. Clin Oral Investig. 2017 Apr;21(3):727-734. doi: 10.1007/s00784-017-2092-4. Review. PubMed PMID: 28255752.
Other references
Dental Elf 30th Jun 2015
Dental Elf – 21st Mar 2011
