Side effects of mandibular advancement splints for the treatment of snoring and obstructive sleep apnea: a systematic review

INTRODUCTION: Occlusal side effects or development of pain and/or functional impairment of the temporomandibular complex are potential reasons for poor compliance or abandonment of mandibular advancement splints treatment for snoring and obstructive sleep apnea. OBJECTIVE: This study aimed at providing a comprehensive review evaluating the craniofacial side effects of oral appliance therapy for snoring and obstructive sleep apnea. METHODS: An electronic search was systematically conducted in PubMed and Virtual Health Library from their inception until October 2016. Only Randomized Controlled Trials whose primary aim was to measure objectively identified side effects on craniofacial complex of a custom-made oral appliance for treating primary snoring or obstructive sleep apnea were included. Studied patients should be aged 20 or older. The risk of bias in the trials was assessed in accordance with the recommendations of The Cochrane Risk of Bias criteria. RESULTS: A total of 62 full-text articles were assessed for eligibility. After the review process, only 6 met all the inclusion criteria. All studies were rated as having a high risk of bias. The most uniformly reported mandibular advancement splint side effects were predominantly of dental nature and included a decrease in overjet and overbite. The risk of developing pain and function impairment of the temporomandibular complex appeared limited with long-term mandibular advancement splint use. CONCLUSION: The limited available evidence suggests that mandibular advancement splint therapy for snoring and obstructive sleep apnea results in changes in craniofacial morphology that are predominantly dental in nature, specially on a long-term basis. Considering the chronic nature of obstructive sleep apnea and that oral appliance use might be a lifelong treatment, a thorough customized follow-up should therefore be undertaken to detect possible side effects on craniofacial complex. It is also important to provide adequate information to the patients regarding these possible changes, especially to those in whom larger occlusal changes are to be expected or in whom they are unfavorable. Long-term assessments of adverse effects of oral appliance therapy, with larger study samples and recruitment of homogenous patient population are still required.