Vol. 6, Issue 1, Part D (2020)

Abstract: The aim of this study is to compare horizontal lip position between Class I and class II division 1 skeletal pattern using five reference planes-Ricketts’ E line, Steiner’s S1 line, Burstone’s B line, Sushner’s S2 line, and Arnett’s lip measurement. Pretreatment lateral cephalograms of 80 patients (40 males and 40 females) were divided into 40 Class I (ANB 2˚±2˚) and 40 Class II (ANB >4˚) subgroups evenly distributed between males and females. The reference panes were measured. The results showed protrusive upper lip in class II subjects compared to class I subjects in both males and females. For lower lip only S2-line showed the statistically significant results. It was concluded that class II skeletal pattern showed protrusive lips in comparison to Class I skeletal pattern with no significant sexual dimorphism.