Uvulo-glosso-pharyngeal dimensions in different anteroposterior skeletal patterns.

The aim of this study was to investigate the uvulo-glosso-pharyngeal dimensions in subjects with different anteroposterior jaw relationship. Cephalometric radiograph of 90 subjects (45 females and 45 males, aged 14-17 years) were divided into three groups according to the ANB angle, ie, group 1, skeletal Class I (ANB angle 1-5); group 2, skeletal Class II (ANB angle >5); and group 3, skeletal Class III (ANB angle <1). In addition, each group was divided into two subgroups according to sex. Statistical analysis was undertaken using analysis of variance and least significant difference test. Pearson's Correlation test was also performed. Sex differences were found in Class I and III subjects. No sex differences were detected in Class II subjects. On average, tongue length was significantly shorter in Class III subjects (P < .05), tongue height was reduced in Class II female subjects, the soft palate was thicker in Class III females and the vertical airway length (VAL) was reduced in Class II male subjects (P < .01). In Class II subjects, the hyoid bone was closer to the mandible vertically and to C3 horizontally compared with Class I (P < .01) and Class III (P < .001) male subjects. Anteroposterior skeletal pattern showed a weak, but significant correlation with inferior pharyngeal airway space (R = -0.24, P = .024), vertical position of hyoid bone in relation to mandibular plane (R = -0.26, P = .014), and anteroposterior position of hyoid bone in relation to C3 (R = -0.561, P = .000). In conclusion, uvulo-glosso-pharyngeal dimensions are affected by anteroposterior skeletal pattern.