Comparison of longitudinal treatment effects with facemask and chincup therapy followed by fixed orthodontic treatment on Class III malocclusion.
10.4041/kjod.2009.39.6.362
- Author:
Nam Ki LEE
1
;
Seung Hak BAEK
Author Information
1. Department of Orthodontics, School of Dentistry, Seoul National University, Korea. drwhite@unitel.co.kr
- Publication Type:Original Article
- Keywords:
Class III malocclusion;
Facemask;
Chin cup;
Longitudinal evaluation
- MeSH:
Humans;
Incisor;
Malocclusion;
Mandible;
Maxilla;
Overbite;
Palatal Expansion Technique;
Retention (Psychology)
- From:Korean Journal of Orthodontics
2009;39(6):362-371
- CountryRepublic of Korea
- Language:English
-
Abstract:
OBJECTIVE: The purpose of this study was to compare the longitudinal treatment effects of facemask with rapid maxillary expansion (FM/RME) and chincup (CC) therapy followed by fixed orthodontic treatment (FOT) in Class III malocclusion (CIII) patients. METHODS: The samples consisted of twenty-one CIII patients who had similar skeletal and dental characteristics before FM/RME or CC therapy and good retention results (Class I molar/canine relationship and positive overbite/overjet) after FOT (Group 1, FM/RME, n = 11; Group 2, CC, n = 10). Lateral cephalograms were taken before (T0) and after FM/RME or CC therapy (T1), and after FOT and retention (T2). Skeletal and dental variables were measured. Mann-Whitney U-test and Wilcoxon signed-rank test were used for statistical analysis. RESULTS: During T0-T1, FM/RME therapy induced forward movement of point A, and labioversion of the upper incisors. Both groups showed posterior repositioning of the mandible. FM/RME resulted in increase of the vertical dimension; however, CC caused an increase in articular angle and decrease in gonial angle. During T1-T2, both groups exhibited forward growth of point A. Group 1 showed forward growth and counterclockwise rotation of the mandible and increase of IMPA; however, Group 2, showed increase of ANS-Me/N-Me and decrease of overbite. CONCLUSIONS: The key factor for successful FM/RME and CC therapy and good retention results might be a harmonized forward growth of the maxilla that could keep pace with the growth and rotation of the mandible.
