Literature Review/Book Review Botulinum toxin for the treatment of bruxism Neslihan Tinastepe, Burcu Bal Ku ¨c ¸u ¨k, Koray Oral Department of Prosthodontics, School of Dentistry, Yeditepe University, Istanbul, Turkey Aims: Botulinum toxin, the most potent biological toxin, has been shown to be effective for a variety of disorders in several medical conditions, when used both therapeutically and cosmetically. In recent years, there has been a rising trend in the use of this pharmacological agent to control bruxing activity, despite its reported adverse effects. The aim of this review was to provide a brief overview to clarify the underlying essential ideas for the use of botulinum toxin in bruxism based on available scientific papers. Methodology: An electronic literature search was performed to identify publications related to botulinum toxin and its use for bruxism in PubMed. Hand searching of relevant articles was also made to identify additional studies. Results: Of the eleven identified studies, only two were randomized controlled trials, compared with the effectiveness of botulinum toxins on the reduction in the frequency of bruxism events and myofascial pain after injection. The authors of these studies concluded that botulinum toxin could be used as an effective treatment for reducing nocturnal bruxism and myofascial pain in patients with bruxism. Conclusion: Evidence-based research was limited on this topic. More randomized controlled studies are needed to confirm that botulinum toxin is safe and reliable for routine clinical use in bruxism. Keywords: Botulinum toxin, Bruxism Introduction The prevalence of bruxism varies widely in the literature, and 6–91% of the adult population, regardless of gender differences, have suffered from this troublesome parafunction. 1 Bruxism is defined as a non-functional stereotyped oral movement disorder characterized by grinding and/or clenching of the teeth and splinting of the jaw muscles. 2 The disorder may occur during sleep and/or during wakefulness. 3 Overloading of the stomatognathic system caused by bruxism may have detrimental effects on the components of the system, such as the teeth, tempo- romandibular joints (TMJs) and related muscles. 4 Tooth pain, mobility, attrition, failures in dental restorations and implants, headache, and disturbance of esthetics have been reported as consequences of this disorder. 5,6 Furthermore, bruxism has been considered to be a risk factor for the presence of signs and symptoms of temporomandibular disor- ders. 4 Although it does not cause life-threatening consequences, bruxism affects quality of life. 7 Numerous theories have been proposed to explain the etiology of bruxism; nevertheless, it remains unclear. Although occlusal disturbances or other morphological factors were believed to be the main causative factor for bruxism, research no longer supports this hypothesis. 8 Instead, central factors such as disturbances of the central dopaminergic system and sleep arousals have received focus. Psychological factors, such as stress and personality characteristics, have also been linked to bruxism. 9 Bruxism can be encountered in patients with a variety of disorders such as cranial-cervical dysto- nia, 10 mental retardation, 11 Huntington’s disease, 12 post-anoxic brain damage, 13 coma, 14 cerebellar damage, 15 Rett syndrome, 16 Whipple’s disease, 17 and the use of dopamine receptor-blocking medications 18 and selective serotonin re-uptake inhibitors. 19 To date, there has been no certain evidence-based treatment modality for ceasing bruxing activity. The main goal of the proposed treatments, including irreversible occlusal adjustment, splint therapy, phar- macological therapies, and cognitive-behavioral app- roaches, is to limit the destructive effects of bruxism on biological structures. 4 Irreversible occlusal thera- pies have been found useless and have not been supported by the current literature. 20 Occlusal splints Correspondence to: N. Tinastepe, University of Yeditepe, School of Dentistry, Department of Prosthodontics, Bagdat cad. No: 238 Goztepe, Istanbul, Turkey. Email: neslihantinastepe@hotmail.com ß W. S. Maney & Son Ltd DOI 10.1179/2151090314Y.0000000022 CRANIOH: The Journal of Craniomandibular & Sleep Practice 2014 VOL. 000 NO. 000 1