Pre- and Post-treatment Changes in Systemic Inflammatory Biomarkers After Oral Appliance Therapy for Obstructive Sleep Apnea: A Systematic Review and Meta-Analysis.

Systemic inflammation often accompanies obstructive sleep apnea (OSA), along with higher chances of heart-related metabolic issues. Although oral appliances serve as an accepted option instead of continuous positive airway pressure (CPAP), their influence on markers of systemic inflammation lacks clear evidence. The aim of this systematic review and meta-analysis was to assess changes in systemic inflammation markers following oral appliance therapy (OAT) among individuals diagnosed with OSA. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards, a systematic review and meta-analysis was conducted. Databases such as PubMed, Embase, Scopus, Web of Science, and Cochrane Library were examined. Studies assessing inflammatory markers before and after therapy among adults with OSA undergoing OAT formed part of the selection. For pooling results, reliance was made upon a random-effects framework. The present research was registered in PROSPERO with the ID CRD420261340212. From a total of 1,974 records screened, six studies qualified for inclusion in the qualitative analysis; among them, two contributed data for each outcome assessed through meta-analysis. Despite pooling outcomes across trials, no meaningful changes emerged in tumor necrosis factor-alpha levels (p = 0.536), nor in C-reactive protein (p = 0.061), or interleukin-6 concentrations (p = 0.230). Consistency between study findings showed minimal variation (I² = 0%). Despite improved clinical results in OSA, OAT shows minor impact on markers of systemic inflammation. To confirm these findings, broader trials with rigorous and uniform designs are needed.