The systematic review of the effect between adjustable and fixed oral appliance on ventilation of obstructive sleep apnea hypopnea syndrome

Abstract

Objective To evaluate the efficacy of adjustable oral appliance (OA)on ventilation of patients with obstructive sleep apnea hypopnea syndrome (OSAHS). Methods Databases were searched from Junuary 1990 to July 2014 for randomized controlled trials on the use of adjustable OA for the promotion of ventilation in OSAHS. Meta analysis was performed with RevMan5.2 software, and descriptive analysis of the data that could not be converted and merged was performed. Results Totally 6 RCTs involved, including 1 109 patients, which involved 4 random parallel controlled trials and 2 random crossover controlled trials. Meta-analysis showed that adjustable OA were associated with a decreased apnea-hypopnea index (AHI)[fixed effect model, WMD=-2.38, 95%CI (-3.59--1.17), P<0.01]and an improvement in minimum arterial oxygen saturation (SaO2)[randomized effect model, WMD=3.09, 95%CI(1.16-5.02), P<0.01]of OSAHS patients. The descriptive analysis showed that the difference in the sleep score was not statistically significant because the data could not be converted. Conclusions Compared to fixed oral appliance, adjustable oral appliance produced greater effect in reduction of AHI and the improvement in minimum SaO2, but the sleep score is not improved significantly, the large sample and multi-center randomized controlled test needs to be designed for the verification of comprehensive effect of adjustable oral appliance. Key words: Obstructive sleep apnea hypopnea; Oral appliance; Systematic review