Abstract:
This study aimed to evaluate cephalometrically the dentoskeletal and soft tissue
changes of Class I malocclusion subjects treated orthodontically with extraction of
four first premolars. The sample consisted of 43 patients (26 females and 17 males),
with Class I malocclusion treated orthodontically with extraction of the four first
premolars, with mean initial age of 14.31 years (sd=2.48), mean final age of 16.57
years (sd=2.76), and mean treatment time of 2.25 years (sd=0.82). The initial and
final lateral cephalograms of each individual were evaluated, and the cephalometric
variables were measured with the aid of Dolphin program. The intragroup comparison
of the initial and final stages, indicating the changes with treatment, was performed
with the dependent t test. With treatment with extraction of the four first premolars,
there was maxillary retraction, improvement of maxillomandibular relationship and
increased of the lower anterior face height. Regarding the maxillary dental
component, there was significant retraction, verticalization and extrusion of the
maxillary incisors and molar mesialization. Regarding the mandibular dental
component, there was significant retraction, lingualization and extrusion of the
mandibular incisors and molar mesialization. There was also a significant decrease in
overjet, and retrusion of the upper and lower lips.
