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

Evaluation of mandibular morphology in different facial types

The purpose of this study was to evaluate mandibular morphology in different facial types using various parameters. This study was conducted on lateral cephalograms of a total of 110 subjects, which included 55 males and 55 females between the age of 18-25 years having a mean of 22.3 years for males and 21.5 years for females. The sample was divided into normodivergent, hypodivergent, and hyperdivergent subgroups based on Jarabak's ratio. Symphysis height, depth, ratio (height/depth) and angle, antegonial notch depth, ramal height and width, mandibular depth, upper, lower, and total gonial angle, and mandibular arc angle were analyzed statistically and graphically. It was found that the mandible with the vertical growth pattern was associated with a symphysis with large height, small depth, large ratio, small angle, decreased ramus height and width, smaller mandibular depth, increased gonial angle, and decreased mandibular arc angle in contrast to mandible with a horizontal growth pattern. Sexual dichotomy was found with mean symphysis height and depth in the female sample being smaller than in the male sample, but symphysis ratio was larger in the female sample; males having greater ramus height and width, mandibular depth than females. The mandible seemed to have retained its infantile characteristics with all its processes underdeveloped in hyperdivergent group