Analysis of von spee's curve in class-I malocclusion

Aim: to investigatethe depth of von spee's curvein class i malocclusion. study design: cross sectional methods: the research was conceived at department of orthodontics,de'montmorency college of dentistry,lahore; involving one hundred lateral cephalograms and castsof class i malocclusion subjects (49 male,mean age:14.9 ±1.6 years; 51females,mean age: 15.3±1.4 years) were included. the depth of the curve was calculated on lateral cephalograms as perpendicular distance from incisal edge of lower central incisor to the lower border of mandible (l1-mp),distobuccal cusp tip of the lower second molar (m7-mp) to lower border of mandible,the deepest point of the von spee's curve to lower border of mandible (s-mp),and proportioned with each other. results: results showed that the mesio-buccal part of the lower first molar was the deepest curve area,and eruption of lower incisors (l1-mp/s-mp) was more related to depth of von spee's curve as compared to eruption of lower molars (m7-mp/s-mp). conclusion: vertical eruption of the lower incisors made a significant contribution to the von spee's curve depthin class onesubjects.