Comparison of symphysis morphology in normodivergent patients of the short and normal mandible

Abstract

Objective: To compare the morphology of symphysis in normodivergent patients of short and normal mandible attending outpatient department of large public sector dental hospital of Karachi, Pakistan. Methods: This was a prospective observational study that was carried out at the outpatient department of the orthodontics, Sindh Institute of Oral Health Sciences, from June-2020 to December-2020. The study included 70 (35 in each group) patients with a normal angle MMA over the range of 25.5° ± 5.3°. McNamara analysis has been carried out including all the patients and dividing into two group's i.e., normal mandible and short mandible. On cephalogram, perpendicular distance from Pog to B-Me line, angle symphysis vertical dimension (B-B1-Gn), and angle symphysis convexity (B-Pog-Me), were measured for all patients. Results: Out of seventy (70) patients, there were 24 (34.3%) males and 46 (65.7) females. Patients were equally divided into two groups, i.e., short 35 (50.0%) and normal mandible 35 (50.0%). The mean angle of symphysis convexity, symphysis vertical dimension, and anterior prominence of symphysis of participants were 124.6 ± 42.8, 49.9 ± 4.7, and 4.1 ± 1.1 respectively. Patients with short mandible were found to have significantly higher in symphysis convexity as compared to patients of normal mandibular, i.e., 136.54 ± 3.55 and 112.74 ± 58.53 respectively, (p-value= 0.022). Conclusion: Symphysis convexity was found greater in short mandible patients showing that in short mandible patients, symphysis was flatter anteriorly, less convex, and less prominent.