3D orthodontic imaging in children across the age spectrum, and correlations with obstructive sleep apnea.

STUDY OBJECTIVES: To determine baseline facial convexity measurements in children with OSA, across the age spectrum.

METHODS: Polysomnogram, stereophotogrammetry, and biometric data were collected from children aged 0-18 years who were being investigated for OSA. Analyses evaluated differences in facial convexity according to OSA severity and other sleep parameters, while adjusting for age, ethnicity and sex.

RESULTS: 91 children, aged 0.05 to 16.02 years, met the inclusion criteria for this study. Initial analysis showed that the logarithm of age had a significant effect on facial convexity ( p = 8.3· 10-7 ) with significant effects of sex (p=1.3· 10-2 ), while excluding OSA. Ordinal logistic regression taking into consideration age, sex, weight, height and ethnicity, with OSA severity categorized as OAHI negative, mild, moderate or severe, showed that facial convexity was associated with OSA severity (p=2.2· 10-3 ); an increasing obtuse angle of convexity, increased the tendency to be classified as having severe OSA.

CONCLUSIONS: Using 3D-imaging, we found an added impact of infancy on changes of facial convexity with age. While modelling could describe facial convexity without any OSA-associated sleep parameters, differences in facial convexity were present amongst groups with different levels of OSA severity adjusted for growth (age, weight, and height), sex, and ethnicity. The method provides a safer and cheaper alternative to other medical imaging techniques in children and holds potential for future use in studies of cranio-facial structure.