RESUMEN
Treatment with or without extraction in class II division 1 cases and their effect on the skeletodental and soft tissues in orthodontic treatment are in debate. Assessing the changes of hard and soft tissues in class II division 1 patients can evaluate facial esthetics following different treatment plannings. The purpose of this study was to compare the changes in subjects with class II division I malocclusions treated with and without extraction. Lateral cephalograms, photographic pictures, OPG radiographic and dental casts of 80 class II division 1 patients aged 12-17 [mean age: 13.6 +/- 1.7], among 900 referred patients to private office, were evaluated at two stages: Pretreatment and posttreatment. 40 patients [20 males and 20 females] had premolar extraction and 40 patients [20 males and 20 females] were treated non-extraction using head gear. All of them were treated with classic edgewise [0.22] system. Eighteen hard and 10 soft tissue landmarks were identified on each cephalogram. All landmarks were identified and checked. Thirty-six skeletal, dental and soft tissue linear and angular measurements were derived. Pearson Rank correlation and student t tests were used to analyze the data and compare the incremental changes between the groups before and after treatment. Absolute dimension within each sex and in extraction group were recorded before and after the treatments. Significance level for statistical comparisions was predetermined at p