ABSTRACT

The purpose of the current study was to assess the effect of upper incisor protrusion on the upper lip, a commonly utilized orthodontic treatment procedure. Twelve subjects with indication of upper incisor protrusion as a result of orthodotic treatment plan were selected. The study group consisted of eight girls and four boys with chronological ages 15.00±1.10 years and skeletal ages 15.30+0.80 years. Subjects were treated by “Modified Edgewise Techniques” for 6.42±2.19 months and 2.38±0.96 milimetres of protrusion and 9.04±4.72 degrees of labioversion of the upper incisors were obtained. The increases in the protrusion and labioversion of upper incisors were found to be nonsignificant as a result of the bioistatistical analysis. The advancement in the upper lip was found to be significant. The forward movement of the upper lip was not found to be related to the protrusion and the labioversion of the upper incisors.