Evaluation of lips thickness to the E-line and S-line in a Nigerian population.

Evaluation of lips thickness to the E-line and S-line

Abstract

Background: Soft tissue structures, such as the lips, their positions, and their relative proportions, are important components in clinical analysis of orthodontic, maxillofacial, and plastic surgery patients. Their assessment is usually with a view to arriving at a decision regarding treatment planning as to whether to maintain or to improve the soft tissue profile. Lip length and thickness may affect aesthetic facial proportions by influencing both dental and facial symmetry.

Aim: To investigate the thickness, length and anteroposterior position of the lips using the E-line and S-line in a Nigerian sample.

Method: Ninety-five lateral cephalometric radiographs of patients aged 17 – 38-years with a skeletal pattern I dental base were analyzed. The soft tissue profile outline was traced including the upper and lower lips and the E-line drawn from the pronasale to the pogonium.  The S-line was drawn from the subnasale to the pogonium to analyze the lips prominence. Descriptive analysis, chi-square and independent student’s t-test was used to study the difference between variables and gender. The level of significance was set at p = < 0.05.

Results: The mean age of participants was 18.12 ± 6.69 years. The upper and lower lips lengths were 25.82±2.65mm and 49.48±5.39mm, and the thickness was 17.39±2.39mm and 20.32±2.75mm, respectively. The prominence of the upper and lower lips with reference to the E-line was 4.37±2.67mm and 8.14±2.51mm respectively. The mean gender difference of upper and lower lips prominence to the ‘E’ line was 2.3mm and 1.6mm and these were statistically significant.

Conclusion: There was a statistically significant difference in upper lip thickness between genders. Both the upper and lower lips were prominent when compared to the Ricketts and Steiners line and were also statistically significant between genders.