Cephalometric evaluation of pharyngeal airway in different skeletal patterns

Background: Functional examination of respiratory system plays an important role in diagnosis and treatment planning.Any abnormalities or obstruction in the respiratory system may lead to functional imbalance and changes in the craniofacial structures leading to malocclusions. Aims & Objective:The aim of this study is to evaluate if the upper and lower pharyngeal airway dimensions of subjects aged above 18 years will be affected by different skeletal patterns.Materials and Methods: Lateral cephalogram of 21 subjects were used for this study .Fourteen linear cephalometric airway measurements are used to evaluate the pharyngeal airway dimension at various levels.The Cephalometric variables (measurements) used to measure pharyngeal airway: Ba-ad1 mm, Ba-ad2 mm, Ba-PNS mm, Ptm-ad1 mm, Ptm-ad2 mm,PNS-ppw1 mm, apw2-ppw2 mm, apw3-ppw3 mm, hy-apw2 mm, hy-apw3 mm, -PNS mm, McNamara's upper and lower pharynx dimension.The values were tabulated and statistical analysis was performed using the ANOVA & post-hoc Bonferroni test.Result: Statistically not significant in upper and middle pharyngeal width.Statistical significance is seen only in lower pharyngeal width(apw2-ppw2) between Class II and class III groups with the level of significance being (p<0.015). Conclusion:According to the study only lower pharyngeal dimension was affected in class II and class III pattern.This is probably due to the position of mandible in a retruded or protruded position respectively.We also observed that the position of hyoid bone varied in different skeletal patterns which maybe also be the reason for variation in pharyngeal dimension for which further studied has to be conducted.