Comparison Between Antegonial Notch Depth, Symphysis Morphology and Ramus Morphology Among Different Growth Patterns In Skeletal Class I And Class II Subjects

In orthodontics and dentofacial orthopaedics, a thorough knowledge of growth and development is essential in order to understand various factors that contribute as to how particular type of growth takes place. When planning of orthodontic treatment for malocclusion, one has to take into account the growth pattern, because it would considerably affect success of the treatment. Aim: The purpose of this study was to compare between antegonial notch depth, symphysis morphology, and ramus morphology in different growth patterns in skeletal class I and class II subjects. Materials and Methods: In this study, a total of 60 cephalograms were taken which comprised 30 cephalograms in skeletal class I and 30 cephalograms of skeletal class II patients. The groups were further divided into 3 groups namely average, horizontal, and vertical growth patterns based on jarabak’s ratio. Antegonial notch depth, symphysis width and symphysis angle, and ramus height were measured and compared between the growth patterns and between class I and class II skeletal patterns. Statistical Analysis: An analysis of variance (ANOVA) test was performed to determine the comparison between groups for all these variables in both skeletal class I and class II. Independent ‘t’ test was done to determine the comparison between skeletal class I and class II subjects for all variables. Mean and SD values for all variables were determined for all the groups. Results: Depth of antegonial notch was found to be greater in vertical growth patterns compared to horizontal and average growth patterns. Large symphysis angle and symphysis width was noted in horizontal growth pattern. Increased ramus height was noted in horizontal and average growth patterns. There was no significant difference between skeletal class I and class II malocclusion for all parameters. Conclusion: The morphology of the various parts of the mandible was found to vary significantly depending on the vertical growth pattern irrespective of the sagittal growth of the mandible.