Comparison of Dental Arch Width and Length Parameters in Patients With Obstructive Sleep Apnea and a Control Group: A Pilot Study

Study Objective: Limited data suggest a smaller, narrow maxilla can lead to a decreased oropharyngeal volume (OPV). However, past studies have used two-dimensional lateral cephalometric radiographs. The specific aim of this study is to assess how maxillary arch parameters relate to oropharyngeal volume calculated from three-dimensional cone beam computed tomography (CBCT) images. An additional aim was to compare these dimensions in a group of African-American patients with obstructive sleep apnea (OSA) with a group of healthy control patients. Methods: Sixteen full-head CBCT images in the closed-mouth anatomic position were obtained from adult male African-American patients with a diagnosis of OSA. The OPV was measured by counting corresponding voxels that are digitally isolated from the threedimensional CBCT images after segmentation. Axial plane images of the same volume were used to measure intercanine width, intermolar width, arch length, and arch perimeter. In addition, 16 CBCT images were obtained from the control group of adult male African-American patients matched for age with no prior diagnosis of OSA. Each of the maxillary arch parameters was tested for correlation with oropharyngeal volume and compared between the two groups. Results: Reliability was tested and for all parameters the intraclass correlation coefficient was greater than 0.95 (0.97-1.00). The OSA group was significantly older than control patients (41.3+11.3 and 31.9±6.9 years, respectively). After accounting for multiple comparisons, the minimum cross-sectional area was the only parameter significantly different between groups (P = 0.0014). Minimum cross-sectional area was found to be a good-excellent predictor of OSA (area under receiver operating characteristic curve = 0.89). A cutoff point of 111 mm was determined for minimum cross-sectional area between groups. Conclusion: The CBCT-based imaging analysis produces reliable measurements for all parameters. The current findings suggest that maxillary arch width and length do not contribute to a smaller oropharyngeal airway. Minimum cross-sectional area is a good-excellent predictor of OSA in African-American adult males.