Nasolabial angle variation caused by anterior retraction on cases treated with extraction of four premolars applying the Edgewise technique

Abstract

This study aims to verify the occurrence of nasolabial angle variation caused by upper incisors retraction on cases treated with the extraction of four premolars. This sample consisted of 30 he- adtellings – in lateral norm - of young Brazilian patients, with no regards to gender, presenting Class II/Div. I malocclusion, trea- ted with the Edgewise Technique by students of the mastership course in Orthodontics at Univer- sidade Metodista de São Paulo. Measurements of the cephalome- tric analysis have shown a signi- ficative statistical increase of the nasolabial angle between the end of the leveling stage of treatment and the end of retraction, and be- tween the beginning of treatment and the end of retraction. Thus, it may be concluded that patients presenting Class II/Div. I maloc- clusion, treated with extraction of four premolars, have shown chan- ges on the facial profile caused by upper incisor retraction, mainly regarding the upper lip. Key words: nasolabial angle, Edgewise technique, premolar extraction.