Evaluation of relationship between pharyngeal airway space and varying dimensions of maxilla and mandible.

Aim: Craniofacial abnormalities such as maxillary retrusion, mandibular retrognathism, short mandibular body, and downward and backward rotation of the mandible in hyperdivergent patients are considered to be the most important risk factor for upper airway obstruction. The aim of the study is to analyze the influence of maxillary and mandibular morphology on pharyngeal length. Materials and Methods: The study sample includes 146 pretreatment lateral cephalographs of both male and female patients aged between 18 and 30 years. The study sample was divided into three groups: Group I – Class I skeletal relationship, Group II – Class II, and Group III – Class III. Each group is further divided into three subgroups according to the growth pattern (A – horizontal, B – average, and C – vertical). The lateral cephalograms were traced both manually and digitally using FACAD imaging software. Results: Comparison of mean maxillary, mandibular, and airway dimensions done using one-way analysis of variance proclaims that the means of all the parameters of the study are statistically significant with P < 0.05 except the upper pharyngeal space. Pearson correlation test reveals a statistically significant positive correlation between the height of the ramus and the lower pharyngeal space. Conclusion: The upper pharyngeal space is reduced in Class III, and the lower pharyngeal space is reduced in Class II and Class III malocclusions. The airway dimension decreased in vertical growth pattern in all the skeletal malocclusion groups. Upper and lower pharyngeal space has a negative correlation with ANS-PNS (maxillary length) and length of the body of the mandible, respectively. [ABSTRACT FROM AUTHOR]