• Janeta Chavanavesh D.D.S.
• Sirima Petdachai D.D.S., Ph.D.
• Vannaporn Chuenchompoonut D.D.S., Ph.D.

Objective To assess sexual dimorphism and correlation among pharyngeal airway dimensions, bony
and soft tissue variables, and skeletal ages.

Materials and Methods Four hundred and eighteen pretreatment lateral cephalometric radiographs
(183 males, 235 females) of growing Thai orthodontic patients (6-20 years old; mean age, 13.95±3.62
years; divided into 3 skeletal ages, pre-pubertal (CS 1,2), pubertal (CS 3,4), and post-pubertal
(CS 5,6)), Faculty of Dentistry, Chulalongkorn University were collected from 2007-2014.
Twelve angular, 13 linear, and 3 area cephalometric measurements were analyzed. Sexual dimorphism
was assessed by Studentûs t-test. Pearsonûs and Spearmanûs correlation coefficients were applied
to explain variable correlations, including the new angular measurements and the existing linear
measurements of tongue and hyoid positions.

Results Sexual dimorphism was found only in the post-pubertal period. Nasopharyngeal, oropharyngeal,
and total pharyngeal area measurements, and airway width at the level of tongue base highly and
positively correlated with vertical tongue and hyoid position, tongue length, and skeletal ages. Other
airway variables also showed significant correlation to mandibular position, vertical and horizontal
hyoid and tongue position, and tongue thickness. Angular measurements of tongue and hyoid
horizontal position highly correlated with linear measurements. Angular measurements of tongue and
hyoid vertical position showed significantly moderate to high correlation with linear measurements.

Conclusion Males had larger airway dimensions than females in post-pubertal period. Skeletal ages,
hyoid position, tongue position and dimension, including mandibular position correlated with upper
pharyngeal airway dimensions. The new angular measurements might be easier and practical
parameters used to measure hyoid and tongue position.

(CU Dent J. 2015;38(Suppl):37-52)