Mentolabial sulcus: An esthetic-based classification

Objectives: The objectives of this study were to study the mentolabial sulcus in Nepalese, to compare the sulcus between male and female, and to classify the sulcus according to the angle. Materials and Methods: This study was conducted in 160 university students (65 males and 95 females) between April and September 2016. Photographs of all the students were taken using a digital camera. Mentolabial sulcus angles were measured from the lateral photographs using an angle instrument. The data were analyzed using SPSS 22. The comparison of sulcus between male and female was done using two-sample t-test at 95% confidence interval. Results: The mean mentolabial sulcus angle in Nepalese was 118.19° ±12.28° (male: 119.43° ± 9.99° and female: 117.61° ± 13.23°). There was no statistically significant difference of sulcus angle between males and females (P = 0.098). The sulcus was classified as deep, average, and shallow in males and females. In total students, the average was more predominant followed by deep and shallow. Conclusions: The mean mentolabial sulcus angle in Nepalese was 118.19° ± 12.28°, in male was 119.43° ± 9.99°, and in female was 117.61° ± 13.23°. The sulcus was classified as deep, average, and shallow. There was no statistically significant difference of sulcus angle between males and females. The average type of sulcus was more predominant in Nepalese.