Comparison of velum morphologies using cephalometry and dental CBCT

Abstract

Objectives: The soft palate in normal individuals exhibits morphological variety on cephalometry. The purpose of the present study was to explore its causes and investigate its possible effects in clinical practice. Methods: Cephalometric and cone-beam computed tomography (CBCT) data for 30 subjects were collected. The morphology of the soft palate on cephalometry was classified into two main types, eyebrow shape and spoon shape. Comparisons between these two types on both cephalometric and CBCT images were made. Results: Comparing these two types, there was a significant difference in the distance between the tip of the uvula and the palatopharyngeus (p < 0.01) as well as in the angle between the uvula and the palatopharyngeus (p < 0.01). The velar length on CBCT imaging was longer than that on cephalometry for the spoon-shape group (p < 0.01) and the overall subjects (p < 0.01). Conclusions: Based on the present results, we speculate that overlapping of the palatopharyngeus and the uvula, which is mainly determined by their relative positions, contributes to the contour of the soft palate on cephalometry. This overlapping phenomenon partly explains the morphological variety of the soft palate on cephalometry, and should be considered during measurement and evaluation of the soft palate.