Impact of Mandibular Advancement Devices on Temporomandibular Disorders and Quality of Life in Obstructive Sleep Apnea Syndrome Patients: A Retrospective Study

Background: Obstructive sleep apnea syndrome (OSAS) is a prevalent sleep-related breathing disorder associated with significant systemic complications and reduced quality of life. Mandibular advancement devices (MADs) represent an established alternative therapy for patients who cannot tolerate continuous positive airway pressure (CPAP). However, concerns remain regarding their potential effects on temporomandibular disorders (TMD). Materials and Methods: This retrospective exploratory study analyzed clinical records of 26 patients (mean age 55.4 ± 5.8 years) with polysomnography-confirmed OSAS and baseline TMD-related symptoms treated with a custom-made monobloc MAD. Clinical parameters were evaluated at baseline (T0) and after approximately 6 months of therapy (T1). Outcomes included apnea–hypopnea index (AHI), Epworth Sleepiness Scale (ESS), Fonseca Anamnestic Index, and health-related quality of life assessed using the SF-36 questionnaire. Repeated measures ANOVA and linear regression analyses were performed. Results: After six months of MAD therapy, a significant reduction in AHI was observed (30 ± 13.76 vs. 10.87 ± 3.9; p < 0.00001). Daytime sleepiness significantly decreased (ESS: 9.31 ± 3.53 vs. 3.38 ± 1.77; p < 0.00001). TMD symptom severity also decreased significantly according to the Fonseca Index (33.85 ± 17.74 vs. 10.00 ± 8.94; p < 0.00001). Quality of life scores improved significantly (SF-36: 41.15 ± 9.52 vs. 65.38 ± 5.82; p < 0.00001). Linear regression analysis showed no significant association between changes in AHI and changes in TMD symptoms, ESS scores, or quality of life. Conclusions: Within the limitations of this retrospective study, MAD therapy was not associated with symptom aggravation of temporomandibular disorders in patients with pre-existing TMD symptoms. Significant improvements in respiratory parameters, daytime sleepiness, and quality of life were observed after six months of therapy.