Is there enough evidence that mouthguards do not affect athletic performance? A systematic literature review

Background Although there is evidence that mouthguards prevent orofacial trauma occurrence during sport practice, the influence of this device on athletic performance has not been systematically quantified. Objectives We aim to systematically review the literature to determine the effect of mouthguards on athletic performance and if the type of mouthguard influences this overcome. Materials and methods A comprehensive search was performed in the Systematic Electronic Databases: Pubmed, Scopus, Web of Science and the Cochrane Library from their inception to February 2017. The publications were grouped based on their outcome: (i) the use of mouthguards; or (ii) the type of mouthguards. We conducted descriptive analyses and quality assessments of the included studies. Results The search identified 489 citations. After screening the studies, we identified 15 trials comprising a population of 312 athletes. According to the risk of bias evaluation, nine studies were considered 'high' risk of bias, and six 'low' risk of bias. Overall, custom-made mouthguards did not interfere or improve athletes' performance when compared with the control group (without mouthguard). Custom-made mouthguards showed the smallest range of changes in players' performance compared with other types of mouthguards. Conclusions This systematic review provides evidence for sports professionals to advocate the use of custom-made mouthguards to prevent injury, and these devices do not impair performance. The scientific evidence should be interpreted carefully because there is a great variability in outcome measures and lack of important methodological details.