Upper and lower pharyngeal airway space in West-Tamil Nadu population

AIM: To compare the upper and lower pharyngeal airway (LPA) width in Class II malocclusion patients with low, average, and high vertical growth patterns. STUDY DESIGN: Cross-sectional analytical study. MATERIALS AND METHODS: Pretreatment lateral cephalometric films of 90 Class II subjects were used to measure the upper and LPAs. The inclusion criteria were subjects of West-Tamil Nadu, aged between 14 and 25 years, only skeletal Class II subjects of either gender and no pharyngeal pathology at initial visit. The sample comprised a total of 90 Class II subjects divided into three groups according to the vertical facial pattern: Normodivergent (n = 30), hypodivergent (n = 30), and hyperdivergent (n = 30). The assessment of upper and LPAs was done according to McNamara's airway analysis. STATISTICAL ANALYSIS: The intergroup comparison of the upper and LPAs was performed with one-way analysis of variance and the Tukey test was used to compare among the various vertical patterns. RESULTS: Skeletal Class II subjects with hyperdivergent facial pattern showed statistically significant narrow upper pharyngeal width when compared to normodivergent and hypodivergent facial patterns. No statistically significant difference was found in the lower pharyngeal width in all three vertical facial growth patterns. CONCLUSION: Subjects with Class II malocclusions and hyperdivergent growth pattern have significantly narrow upper pharyngeal airway space when compared to other two vertical patterns. Narrow pharyngeal airway space is one of the predisposing factors for mouth breathing and obstructive sleep apnea.