Analysis of Class II patients, successfully treated with the straight-wire and Forsus appliances, based on cervical vertebral maturation status.
OBJECTIVE
To assess skeletal and dental changes in patients successfully treated with the Forsus appliance based on cervical vertebral maturation status.


METHODS
Forty-seven Class II patients, successfully treated with the Forsus appliance, were divided into peak and postpeak growth groups determined immediately prior to Forsus placement. The mean (SD) ages of the peak and postpeak groups were 13.4 (1.0) and 14.1 (1.3) years, respectively. Superimpositions of initial, Forsus placement, Forsus removal, and final cephalometric radiographs were completed, allowing the measurement of changes during three treatment phases.


RESULTS
There were no significant differences between groups during treatment phase 1 (alignment/leveling), with both groups demonstrating a worsening of the Class II molar relationship. However, during treatment phase 2 (Class II correction), patients within the peak group demonstrated significantly higher mean apical base, mandibular and molar changes, and an increased rate of change compared with those in the postpeak group. No significant differences were observed during treatment phase 3 (detail/finishing).


CONCLUSIONS
Following an initial worsening of the Class II molar relationship as a result of straight-wire appliance effects, Forsus appliance treatment initiated during cervical vertebral maturation status (CS) 3-4 elicits more effective and efficient correction of Class II molar relationships than when initiated during CS 5-6. Data support that these effects are due mainly to maxillary skeletal and dentoalveolar restraint during a period of more rapid mandibular growth.
a  Orthodontic resident, Tri-Service Orthodontic Residency Program, Air Force Postgraduate Dental School, Joint Base San Antonio and Uniformed Services University of the Health Sciences, Lackland, Tex.
David F
DF
Servello
Drew W
DW
Fallis
Lisa
L
Alvetro
D000293:Adolescent; D000365:Age Determination by Skeleton / Q000379:methods*; D002508:Cephalometry / Q000379:methods; D002574:Cervical Vertebrae / Q000254:growth & development*; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007180:Incisor / Q000473:pathology; D008297:Male; D008312:Malocclusion, Angle Class II / Q000628:therapy*; D008334:Mandible / Q000254:growth & development / Q000473:pathology; D008437:Maxilla / Q000254:growth & development / Q000473:pathology; D008963:Molar / Q000473:pathology; D009295:Nasal Bone / Q000254:growth & development / Q000473:pathology; D017289:Orthodontic Appliances, Functional; D012189:Retrospective Studies; D016896:Treatment Outcome
Class II correction; Forsus, Class II; Growth modification; Growth status