Cephalometric changes in Class II division 1 patients treated with two maxillary premolars extraction

OBJECTIVE: The purpose of this study was to evaluate the cephalometric alterations in patients with Angle Class II division 1 malocclusion, orthodontically treated with extraction of two maxillary premolars. METHODS: The sample comprised 68 initial and final lateral cephalograms of 34 patients of both sex (mean initial age of 14.03 years and mean final age of 17.25 years), treated with full fixed appliances and extraction of the first maxillary premolars. In order to evaluate the alterations due the treatment between initial and final phases, the dependent t test was applied to the studied cephalometric variables. RESULTS: The dentoskeletal alterations due to extraction of two maxillary premolars in the Class II division 1 malocclusion were: maxillary retrusion, improvement of the maxillomandibular relation, increase of lower anterior facial height, retrusion of the maxillary incisors, buccal inclination, protrusion and extrusion of the mandibular incisors, besides the reduction of overjet and overbite. The tissue alterations showed decrease of the facial convexity and retrusion of the upper lip. CONCLUSIONS: The extraction of two maxillary premolars in Class II division 1 malocclusion promotes dentoskeletal and tissue alterations that contribute to an improvement of the relation between the bone bases and the soft tissue profile.