Cephalometric Analysis of Upper Airways in Class I Malocclusion in Adults in Qazvin

Background and purpose: Unusual enlargement of nose and pharyngeal (nasopharynx) can disrupt the flow of air through the nose. The aim of this study was to investigate the cephalometric parameters in the upper airways. Materials and methods: A retrospective descriptive study was performed using the digital lateral cephalometric radiographs of 32 adults with class I (CL I) malocclusion and no history of night apnea. The radiographs were obtained from the archives in Qazvin Orthodontics Department of Dentistry School and private clinics. Coefficient of variations and Pearson correlation were calculated in SPSS. Results: There was positive Significant correlation (r= 0.761) between tongue length and tongue height, length of the soft palate, and maximum thickness of the soft palate but negative significant correlation was found between tongue length and hypo pharnzhyal air space (r= -0.422) (P= 0.01). There was positive significant correlation (r= 0.444) between tongue height and length of the soft palate and maximum thickness of the soft palate. Also, there was positive significant correlation between over pharyngeal air space and hypo pharyngeal air space and posterior air space (r= 0.551) (P= 0.014). There was positive significant correlation between hypo pharyngeal air space and posterior air space, vertical position of vallecula, and horizontal position of vallecula (P= 0.017). Posterior air space had a positive significant correlation with horizontal position of vallecula but had a negative significant correlation with length of the soft palate. There was positive significant correlation between length of the soft palate and maximum thickness of the soft palate, and vertical position of vallecula and horizontal position of vallecula. Conclusion: There was no significant difference in cephalometric parameters of the upper air ways in adults in Qazvin with CL I malocclusion. Genetic and environmental effects are the most important factors in these cases.