Orthodontic treatment time in 2- and 4-premolar-extraction protocols.Am J Orthod Dentofacial Orthop. 2006 May; 129(5):666-71.AJ
The purpose of this study was to compare the treatment times of complete Class II malocclusions treated with 2- and 4-premolar-extraction protocols.
Ninety-seven patients were selected and divided into 2 groups, according to the 2 extraction criteria. Group 1, treated with 2 maxillary premolar extractions, consisted of 49 patients (30 male, 19 female) with a mean age of 14.35 years. Group 2, treated with 4 premolar extractions, consisted of 48 patients (27 male, 21 female) with a mean age of 13.03 years. Treatment times of the groups were compared with the t test.
Treatment times were significantly shorter with the 2-premolar-extraction protocol compared with the 4-premolar-extraction protocol.
Treatment time will be shorter and the occlusal results more predictable with a 2-premolar-extraction protocol compared with 4 premolar extractions.