Assessment and Evaluation of Soft Tissue Measurements between Various Mandibular Divergences in the South Indian Population: A Cephalometric Study

AIM: The aim of this study is to evaluate the association between the mandibular divergent patterns and soft tissue chin (STC) thickness measured at different chin levels in nongrowing patients. METHODOLOGY: Pretreatment lateral cephalograms of 400 adult patients were segregated into four groups based on mandibular divergence pattern defined by the mandibular plane to cranial base angle (average 32° ± 5°), Group I with low angle (below 27°), Group II with medium low angle (28°–32°), Group III with medium high angle (33°–36°), and Group IV with high angle (above 37°). STC thickness was measured between Pog-Pog' (pogonion), Gn-Gn' (gnathion), and Me-Me' (menton), thickness and height of the upper and lower lips were also measured. Statistical analysis was done using one-way analysis of variance followed by post hoc Tukey analysis. RESULTS: A significant difference in the STC thickness at Pog, Gn, and Me was observed among all four groups with hyperdivergent patterns, showing decreased STC thickness than the hypodivergent mandibular pattern. Thickness of the upper and lower lips was greater in hypodivergent mandible, whereas height of the lips was greater in hyperdivergent mandible.