A Cephalometric Comparative Study for Upper Airway Dimensions in Different Craniofacial Growth Patterns
AIM AND OBJECTIVES: To compare different craniofacial patterns with pharyngeal widths. In OSA (Obstructive Sleep Apnea) patients, a mutual association between the pharyngeal structures and the dentofacial patterns has been suggested. The present study was performed to compare the nasopharynx, oropharynx and hypopharynx dimensions of persons with hypodivergent, normodivegent and hyperdivergent facial types and to predict and to facilitate treatment for OSA patients.
Hypothesis: The Null hypothesis for the study was that there is no difference between the upper airway for patients with different growth pattern.
MATERIALS AND METHODS: The sample comprised 60 patients divided into three groups: hypodivergent (n=20), normodivergent (n=20), and hyperdivergent (n=20) according to Jarabak’s ratio and FH-MP angle, which were used to compare the soft tissue airway dimensions. The statistical analysis was performed using Student’s t-Test, one way ANOVA (analysis of variance) and LSD (Least significant difference) test.
RESULT: Overall narrower anteroposterior pharyngeal dimension was found in the hyperdivergent group as compared to the normodivergent group. Whereas, the superior part of upper pharyngeal width in the subjects with hypodivergent growth pattern was significantly narrower than in normal growth pattern groups.
CONCLUSION: In hyperdivergent patients, the narrower anterioposterior dimension of the airway may be due to the skeletal features common to such patients, i.e., posterior vertical maxillary excess, posterior position and decreased mandibular size. The variations of the upper airway may be attributed to the horizontal and vertical growth patterns. Upper airway obstruction and later on OSA may be predisposed by skeletal deficiency.
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