ABSTRACT
In cephalometric and photographic analysis, several reference lines have been used to assess anteroposterior position of the upper and lower lips: E-Line and S-Line being the most commonly used reference lines Aim of this study was to find out the antero-posterior position of lips on photograph using E-line and S-line in patients with orthognathic profile and to establish correlation between lip prominence judged by E-Line and S-Line. The study was conducted on 90 subjects, with orthognathic profile as judged in consensus by orthodontist, prosthodontist, Oral Surgeon, Oral Pathologist and General Dentist and confirmed by lateral cephalogram [ANB 0-4°, Wits Value 0,-lmm] with age range of 12-30 years. E-Line and S-Line were drawn on photograph to assess the prominence of upper Lip and lower lip. SPSS 16.0 was used for statistical evaluation. Antero-posterior position of upper and lower lip with reference to E-line was -7.9+3.33 mm -0.4+3.24 mm respectively and Antero-posterior position of upper and lower lip with reference to S-line was 3.72+2.85 mm and 1.18+3.23 mm respectively. Moreover statistically significant correlation was found r-0.509 between Upper lip to E-Line and Upper Lip to S-Line andm r= 0.861 between Lower lip to E-Line and Lower lip to S-Line