ABSTRACT
Background: Reduction of upper airway (UA) dimensions during sleep is contemplated to cause reduced sleep efficiency (SE) but a definitive association is not affirmed. Efficacy of nasopharyngeal appliance (NPA) in management of UA resistance syndrome (UARS) has not been compared with mandibular repositioning splint (MRS). This study intended to assess relation of UA dimensions to SE and effectiveness of NPA. Materials and Methods: Research had two phases: Case–control study to determine association between UA and SE; randomized control trial (with independent concurrent trial groups and double‑blind design) to analyze treatment outcome with NPA. Subjects were categorized to three groups of 20 in each: A control group of healthy subjects (Group A); two “Randomly Assigned” sample groups of subjects with reduced SE (Groups B and C). Preliminary questionnaire for sleep analysis, Final data collection sheet (first and second case sheets) were recorded, cephalometric variables analyzed, and diagnostic overnight polysomnography was done to match and confirm selection criteria. Three‑dimensional computed tomography was done to analyze airway dimensions before and after appliance placement. ANOVA and post‑hoc tests were used for statistical analysis of results. Conclusions: Reduced UA dimension during sleep is associated with reduced SE; NPA gives better improvement for UARS than MRS.