Dentofacial and soft tissue changes in Class II, division 1 cases treated with and without extractions.
The purpose of this study was to compare the changes in subjects with Class II division 1 malocclusions treated with and without the extraction of four first premolars. Lateral cephalograms on 91 patients (44 extraction and 47 nonextraction) were evaluated at three stages: pretreatment, posttreatment, and approximately 2 years after treatment. The present findings indicate that before treatment, the upper and lower lips were more protrusive relative to the esthetic plane among the subjects treated with four first premolar extractions. After treatment the upper and lower lips were more retrusive in the extraction group, and more protrusive in the nonextraction groups. The extraction group tended to have straighter faces and slightly more upright maxillary and mandibular incisors, whereas the nonextraction group had the opposite tendencies. The average soft tissue and skeletal measurements for both groups were close to the corresponding averages derived from the Iowa normative standards. In general, differences between the groups after treatment were preserved into retention. The present findings indicate that the extraction or nonextraction decision, if based on sound diagnostic criteria, seem to have no deleterious effects on the facial profile.
Bishara
S E
SE
Department of Orthodontics, College of Dentistry, University of Iowa, Iowa City.
Cummins
D M
DM
Jakobsen
J R
JR
Zaher
A R
AR
D000293:Adolescent; D001641:Bicuspid / Q000601:surgery; D002508:Cephalometry; D002648:Child; D005145:Face / Q000033:anatomy & histology*; D005260:Female; D006801:Humans; D008046:Lip / Q000033:anatomy & histology; D008297:Male; D008312:Malocclusion, Angle Class II / Q000628:therapy*; D009971:Orthodontics, Corrective / Q000379:methods*; D014081:Tooth Extraction; D016896:Treatment Outcome