Lip Morphology in Bimaxillary Dentoalveolar Protrusion in Class I and Class Ii Adults

The objective of this study was to compare lip morphology in the young adult population of Pakistani origin, having bimaxillary dentoalveolar protrusion on class I and class II skeletal pattern. This cross sectional comparative study included 100 subjects, 50 with class I skeletal pattern and other 50 with skeletal class II pattern. Age of these subjects ranged from 18-25 years. The sampling included random selection of the subjects. The method comprised skeletal, dental and soft tissue cephalometric analysis made on lateral cephalograms taken in natural head position of the subject. A total of 20 variables were used in the study comprising 6 skeletal, 3 dental and 11 soft tissue variables. Among the skeletal I subjects variables of the sagittal and vertical skeletal analysis showed more or less normal values. Variables of the dental analysis however, determined increased inclinations of the upper and lower incisors and consequent reduction of Frankfurt mandibular incisor angle FMIA. The soft tissue variables showed full profile with greater upper and lower lip vermilion, decreased lip strain, lower lip thickness and deficient upper and lower lip lengths. In skeletal II subjects almost all these variables gave relatively enhanced readings, but difference was not of statistical significance. The study concluded that there is no significant difference in the lip morphology with bimaxillary protrusion on class I and class II skeletal pattern.