Cross-sectional and retrospective study regarding the changes in the spatial position of the hyoid bone and upper airways before and after orthodontic therapy in developing patients with normocclusion

Abstract

ABSTRACT Objective The objective was to study the effect of orthodontic therapy regarding the position of the hyoid bone and upper airways in nighty-one 6–21 year-old Caucasian patients with normoclussion. Methods Nineteen variables were analyzed by teleradiography. The differences were analyzed with the ANOVA test of repeated measures with an intra-group factor for two occasions. Results The statistical analysis revealed a greater influence on the variables Hy-MP (12.3 vs 14.2), Hps-C3 (25.2 vs 28.1), Hpi-C3 (28.8 vs 35.5), H°-C3 (14.4 vs 12.7), Hps-Rg (36.0 vs 42.7), Hpi-Rg (34.1 vs 39.7), USP (16.2 vs 20.2), MPP (12.9 vs 14.8), C3P (10.6 vs 12.8), PNS-Ba (43.5 vs 66.5), PtV-Ad (12.0 vs 17.1) and PtM-Ba (33.9 vs 35.9), and Ad2-SO (24.16 vs 20.87). Discussion Significant differences were observed between most of the airway and hyoid bone variables before and after orthodontic treatment in our Spanish pediatric population, especially in the nasopharynx.