Objectives: The aim of the study was to evaluate the influence of dental arch dimensional changes on pharyngeal airway after extraction treatment in non growing class II division 1 cases.
Materials and Methods:
Pre and post treatment lateral cephalometric radiographs and study casts of twenty eight adult female patients of mean age 21 +/-3 years with class II division 1malocclsions whom underwent fixed orthodontic treatment with extraction of four first premolars were included in this study. Pre and posttreatment lateral cephalograms were digitally analyzed to assess the changes in the upper and lower pharyngeal airway space. The arch perimeter and depth were measured on the pre and posttreatment scanned study models. Descriptive statistics were used to analyze the readings. Student's paired t-test was done to compare the pre and posttreatment mean values of the measurements.
Results: Statistical analysis revealed an insignificant increase in the upper airway and insignificant decrease in the lower airway between pre and post treatment cephalometric measurements. On the other hand, a highly significant decrease was found in the maxillary and mandibular arch perimeter, it also showed a significant decrease in the maxillary and mandibular arch depth between pre and posttreatment values.
Conclusion: The reduction in the arch perimeter and depth parameters did not impair the pharyngeal air way space at non growing class II division 1 cases after orthodontic treatment that entailed extraction of four first premolars with retraction of anteriors.