Possible association between obstructive sleep apnea syndrome and sleep bruxism in adults: an umbrella review.

INTRODUCTION

Bruxism is an involuntary motor activity linked to periodontal changes, temporomandibular disorders, and tooth wear. Obstructive Sleep Apnea Syndrome (OSAS) involves recurrent upper airway obstruction during sleep and may be associated with bruxism and primary snoring. Understanding this relationship could improve diagnosis and clinical management.

OBJECTIVES

To assess systematic reviews to determine whether a bidirectional relationship exists between OSAS and bruxism in adults.

METHODS

An umbrella systematic review was conducted following PRISMA 2020. Systematic reviews with or without meta-analysis examining bruxism and OSAS in adults were included. Searches were conducted in PubMed, LILACS, BVS, SciELO, Scopus, and Embase for studies published from 2000 to January 2026, without language restrictions. Eligible studies used polysomnography-based diagnoses, met PECOT criteria, and were available in full text. Methodological quality and risk of bias were assessed with AMSTAR-2 and ROBIS. Two independent reviewers performed study selection.

RESULTS

From 1726 records, eight systematic reviews were included, only one with a meta-analysis. Most reviews reported frequent coexistence of sleep bruxism and OSAS, possibly due to shared mechanisms like micro-arousals and autonomic activation, though causality remains unclear. Methodological quality was mostly low or critically low, and only three reviews had low risk of bias. Overall, evidence was heterogeneous and limited.

CONCLUSION

Adults with OSAS appear more likely to experience sleep bruxism, indicating a potential bidirectional association. However, heterogeneity and low methodological quality limit the strength of evidence. Well-designed randomized and longitudinal studies are needed to clarify this relationship.