Computerized Tomographic Evaluation of Effects of Mandibular Anterior Repositioning on the Upper Airway: A Pilot Study

Abstract

Statement of problem Snoring is related to narrowing of the upper airway. Treatment options for snoring may have potential side effects or discomfort which may not be tolerated by some patients. Mandibular advancement devices may cause fewer negative side effects than other treatment modatlities and have been advocated as a treatment for snoring. Purpose The aim of the pilot study was to evaluate effects of the anterior mandibular positioner (AMP) on upper airway structures in patients with a snoring problem. Material and methods Fifteen subjects with snoring problems as identified by spouses or close relatives were selected to complete a questionnaire related to snoring, respiratory symptoms, body mass index (BMI), and smoking habits. Computerized tomography (CT) scans were obtained with and without AMP device fabricated as a monoblock of acrylic resin. Measurements of the oropharynx including length (mm), cross-sectional area (mm2), and plane angle (degrees) were made using anatomic landmarks on standardized CT images and lateral scanograms. The data were statistically evaluated using Wilcoxon signed rank test (α=.05). Results When the AMP was inserted, the cross-sectional area of the oropharynx increased by 60 mm2 on average (P<.05). A mean increase of 2.4 mm (range 1-7 mm) was observed in the posterior airway space on lateral scanograms (P<.005). The range for mandibular advancement was between 4 and 8 mm (mean 5.73 mm). Conclusion The primary effect of the AMP was enlargement of the oropharyngeal airway. Within the limitations of this pilot study, the results suggest that CT evaluation of the upper airway structures may be helpful in determining treatment modality and monitoring the effectiveness of the positioner.