Preliminary three-dimensional analysis of tooth movement and arch dimension change of the maxillary dentition in Class II division 1 malocclusion treated with first premolar extraction: conventional anchorage vs. mini-implant anchorage.
10.4041/kjod.2012.42.6.280
- Author:
Heon Mook PARK
1
;
Byoung Ho KIM
;
Il Hyung YANG
;
Seung Hak BAEK
Author Information
1. Department of Orthodontics, School of Dentistry, Dental Research Institute, Seoul National University, Seoul, Korea. drwhite@unitel.co.kr
- Publication Type:Original Article
- Keywords:
Three-dimensional analysis;
Tooth movement;
Arch dimension change;
Class II division 1 malocclusion;
Conventional anchorage;
Mini-implant anchorage
- MeSH:
Bicuspid;
Contracts;
Dentition;
Humans;
Incisor;
Malocclusion;
Mechanics;
Molar;
Tooth;
Tooth Movement
- From:The Korean Journal of Orthodontics
2012;42(6):280-290
- CountryRepublic of Korea
- Language:English
-
Abstract:
OBJECTIVE: This study aimed to compare the effects of conventional and orthodontic mini-implant (OMI) anchorage on tooth movement and arch-dimension changes in the maxillary dentition in Class II division 1 (CII div.1) patients. METHODS: CII div.1 patients treated with extraction of the maxillary first and mandibular second premolars and sliding mechanics were allotted to conventional anchorage group (CA, n = 12) or OMI anchorage group (OA, n = 12). Pre- and post-treatment three-dimensional virtual maxillary models were superimposed using the best-fit method. Linear, angular, and arch-dimension variables were measured with software program. Mann-Whitney U-test and Wilcoxon signed-rank test were performed for statistical analysis. RESULTS: Compared to the CA group, the OMI group showed more backward movement of the maxillary central and lateral incisors and canine (MXCI, MXLI, MXC, respectively; 1.6 mm, p < 0.001; 0.9 mm, p < 0.05; 1.2 mm, p < 0.001); more intrusion of the MXCI and MXC (1.3 mm, 0.5 mm, all p < 0.01); less forward movement of the maxillary second premolar, first, and second molars (MXP2, MXM1, MXM2, respectively; all 1.0 mm, all p < 0.05); less contraction of the MXP2 and MXM1 (0.7 mm, p < 0.05; 0.9 mm, p < 0.001); less mesial-in rotation of the MXM1 and MXM2 (2.6degrees, 2.5degrees, all p < 0.05); and less decrease of the inter-MXP2, MXM1, and MXM2 widths (1.8 mm, 1.5 mm, 2.0 mm, all p < 0.05). CONCLUSIONS: In treatment of CII div.1 malocclusion, OA provided better anchorage and less arch-dimension change in the maxillary posterior teeth than CA during en-masse retraction of the maxillary anterior teeth.
