Soft-tissue treatment changes in Class II Division 1 malocclusion with and without extraction of maxillary premolars.Am J Orthod Dentofacial Orthop. 2007 Dec; 132(6):729.e1-8.AJ
In this study, we compared the soft-tissue changes and posttreatment status after nonextraction and maxillary premolar extraction treatment in patients with Class II Division 1 malocclusion.
Lateral cephalograms of 44 patients, divided into 2 matching groups, were evaluated. Group 1 comprised 22 patients (10 boys, 12 girls) treated nonextraction with initial and final mean ages of 12.50 and 15.12 years, respectively, and a mean treatment time of 2.62 years. This group had an initial mean overjet of 7.97 mm. Group 2 consisted of 22 patients (10 boys, 12 girls) treated with extractions of 2 maxillary premolars with initial and final mean ages of 12.86 and 15.32 years, respectively. The mean treatment time was 2.46 years, and the initial mean overjet was 8.61 mm. Independent t tests were used to compare the initial and final cephalometric status and the treatment changes between the groups.
According to the results, only 1 soft-tissue variable showed a significant treatment change between the groups. However, at the posttreatment stage, there were no significant differences between the soft-tissue variables.
The protocol including extraction of 2 maxillary premolars provides similar soft-tissue results as nonextraction treatment of complete Class II malocclusion.