Stability of anterior open-bite extraction and nonextraction treatment in the permanent dentition.
BACKGROUND
Although stability of anterior open-bite extraction and nonextraction treatment has been investigated, results suggesting that extraction treatment is more stable have not been confronted. Therefore, the purpose of this cephalometric study was to compare the long-term stability of anterior open-bite extraction and nonextraction treatment in the permanent dentition.


METHODS
Group 1 consisted of 21 patients treated without extractions, and group 2 included 31 patients treated with extractions who had orthodontic treatment with fixed appliances. Cephalometric headplates were obtained at pretreatment, posttreatment, and postretention. The groups were compared at these 3 times and during the treatment and posttreatment periods with independent t tests. The number of patients with a clinically significant relapse of the open bite was compared between the groups with chi-square tests.


RESULTS
During treatment, the maxillary incisors had greater retraction amounts, and the mandibular incisors had greater retraction and lingual tipping, and less extrusion in the extraction group. In the posttreatment period, the extraction group demonstrated statistically greater stability of the overbite. However, there was no statistically significant difference in the percentages of patients with clinically significant relapse of the open bite between the groups.


CONCLUSIONS
Open-bite extraction treatment has greater stability of the overbite than open-bite nonextraction treatment.
Janson
Guilherme
G
Department of Orthodontics, Bauru Dental School, University of São Paulo, Bauru, São Paulo, Brazil. jansong@travelnet.com.br
Valarelli
Fabrício Pinelli
FP
Beltrão
Rejane Targino Soares
RT
de Freitas
Marcos Roberto
MR
Henriques
José Fernando Castanha
JF
D000293:Adolescent; D002508:Cephalometry; D016009:Chi-Square Distribution; D002648:Child; D019229:Dentition, Permanent; D005260:Female; D006801:Humans; D008297:Male; D024343:Open Bite / Q000628:therapy*; D009971:Orthodontics, Corrective / Q000379:methods*; D012189:Retrospective Studies; D055502:Secondary Prevention; D018709:Statistics, Nonparametric; D014081:Tooth Extraction