Association between obstructive sleep apnea and temporomandibular disorders: A meta-analysis

Obstructive sleep apnea (OSA) is a very common condition in patients with temporomandibular disorders (TMD). However, there is little evidence of a connection between them.

The aim of this systematic review and meta-analysis is to assess the association between OSA and TMD in adult population.

Case-control, cross-sectional and cohort studies on the association between TMD and OSA were searched in the EMBASE, LILACS, LIVIVO, PubMed/MEDLINE, Scopus, Web of Science, Google Scholar, Open Grey and Pro Quest databases. TMD should be assessed using Research Diagnostic Criteria (RDC/TMD) or Diagnostic Criteria (DC/TMD) and OSA using polysomnography (PSG) and/or a validated questionnaire. The risk of bias was evaluated using the Joanna Briggs Institute Critical Assessment Checklists; and an association meta-analysis was performed. The effect measure included the odds ratio (OR) in dichotomous variables and a 95% confidence interval (CI). Certainty of evidence was determined by analysing groups using the Grading of Recommendations Assessment, Development and Evaluation (GRADE).

Out of the 1024 articles screened, 7 met the inclusion criteria for the qualitative synthesis, and 6 for quantitative analysis. All articles were classified at low risk of bias. A positive association with OSA was found in patients with TMD (OR = 2.61; 95% CI = 2.31, 2.95). A significant association was also found irrespective to the OSA diagnostic methods applied (for studies using PSG + validated questionnaires: OR = 2.74; 95% CI = 2.11, 3.57; for studies using validated questionnaires only: OR = 2.55; 95% CI = 2.22, 2.92). GRADE was moderate.

Patients with TMD presented a significant association with OSA regardless of the OSA diagnostic method (PSG and/or validated questionnaires). OSA screening should be part of the TMD examination routine. Furthermore, due to the different OSA assessment methods used and the small number of studies included, there is a need to include a larger number of studies using PSG to better elucidate this association.