Abstract
The recognition of malocclusion as an important problem in the public dental health services implies the need of carrying out epidemiologic studies and analysing the prevalence rates of malocclusion. The aim of this present article was to determine the prevalence of malocclusion in 410 Lebanese orthodontic patients (258 girls and 152 boys) referred to the Department of Orthodontics Saint-Joseph University Beirut, at DS6 stage, from different geographic locations. The distribution of malocclusion types according to Angle classification and sex and record frequencies of sagittal, vertical and transverse occlusal abnormalities with possible correlation between them. Class II malocclusion was the most frequently seen (49%) whereas Class III, subdivision the least frequently encountered (2.20%). Statistically significant difference was observed in normal Overjet, Overbite, Cross-bite, slight midline deviation, ANB, NL/ML, NSL/ML according to sex and between FMA, NL/ML, NSL/ML in the hypodivergent and hyperdivergent groups, and between ANB –AoBo in the normal and distal groups. Class II female Lebanese patients have a higher motivation for orthodontic therapy, statistically significant difference was found between vertical and sagittal angles.