CORRELATION OF NASOLABIAL ANGLE WITH MAXILLARY INCISOR INCLINATION AND UPPER LIP THICKNESS
Nasolabial angle (NLA) is a key indicator of facial esthetics and plays an important role in extraction decision in clinical orthodontics. The aim of this study is to evaluate correlation of NLA with maxillary incisor inclination (SN-UI) and upper lip thickness (ULT).
Pretreatment cephalometric records of 200 patients with skeletal class I and average vertical proportions were taken after sample size calculation. NLA, ULT and SN-UI were measured on acetate paper sheet attached to lateral cephalogram. Descriptive statics were generated for all the variables involved in the study. Pearson correlation was used to evaluate association between SN-UI and ULT with NLA. A p value < 0.05 was taken as significant.
Mean age of the total sample in this study was 20.28+3.860 years. Sn-UI was 106.90°+8.640° while NLA was 97.62°+9.899°. ULT was found to be 13.20+7.57 mm. A correlation coefficient of -.116 was found between NLA and SN-UI while correlation coefficient of 0.089 was found between NLA and ULT. Both correlations were greater than 0.05 p value.
Maxillary incisor inclination and upper lip thickness show weak and statistically insignificant correlation with nasolabial angle.