Three-dimensional evaluation of tooth movement in Class II malocclusions treated without extraction by orthodontic mini-implant anchorage.
10.4041/kjod.2016.46.5.280
- Author:
Dler ALI
1
;
Hnd MOHAMMED
;
Seung Hwan KOO
;
Kyung Hwa KANG
;
Sang Cheol KIM
Author Information
1. Department of Orthodontics, School of Dentistry, Wonkwang University, Iksan, Korea. sangkim@wku.ac.kr
- Publication Type:Original Article
- Keywords:
Tooth movement;
Class II division 1 malocclusion;
Nonextraction treatment;
Mini-implant anchorage
- MeSH:
Adult;
Bicuspid;
Dentition;
Humans;
Malocclusion*;
Methods;
Molar;
Tooth Movement*;
Tooth*
- From:The Korean Journal of Orthodontics
2016;46(5):280-289
- CountryRepublic of Korea
- Language:English
-
Abstract:
OBJECTIVE: The aim of this study was to analyze tooth movement and arch width changes in maxillary dentition following nonextraction treatment with orthodontic mini-implant (OMI) anchorage in Class II division 1 malocclusions. METHODS: Seventeen adult patients diagnosed with Angle's Class II division 1 malocclusion were treated by nonextraction with OMIs as anchorage for distalization of whole maxillary dentition. Three-dimensional virtual maxillary models were superimposed with the best-fit method at the pretreatment and post-treatment stages. Linear, angular, and arch width variables were measured using Rapidform 2006 software, and analyzed by the paired t-test. RESULTS: All maxillary teeth showed statistically significant movement posteriorly (p < 0.05). There were no significant changes in the vertical position of the maxillary teeth, except that the second molars were extruded (0.86 mm, p < 0.01). The maxillary first and second molars were rotated distal-in (4.5°, p < 0.001; 3.0°, p < 0.05, respectively). The intersecond molar width increased slightly (0.1 mm, p > 0.05) and the intercanine, interfirst premolar, intersecond premolar, and interfirst molar widths increased significantly (2.2 mm, p < 0.01; 2.2 mm, p < 0.05; 1.9 mm, p < 0.01; 2.0 mm, p < 0.01; respectively). CONCLUSIONS: Nonextraction treatment with OMI anchorage for Class II division 1 malocclusions could retract the whole maxillary dentition to achieve a Class I canine and molar relationship without a change in the vertical position of the teeth; however, the second molars were significantly extruded. Simultaneously, the maxillary arch was shown to be expanded with distal-in rotation of the molars.
