Different Traction Positions of Class Ⅱ Elastics in Maxillary Anterior Region with Fixed Multibracket:A Finite Element Analysis
10.16156/j.1004-7220.2025.04.008
- VernacularTitle:固定矫治上前牙区不同Ⅱ类牵引位置的有限元分析
- Author:
Wenlei DENG
1
;
Siyang LUO
;
Junmei ZHANG
;
Zhijun ZHENG
Author Information
1. 贵州医科大学口腔医学院,贵阳 550004
- Publication Type:Journal Article
- Keywords:
Class Ⅱ elastics;
Class Ⅱ malocclusion;
traction position;
fixed multibracket
- From:
Journal of Medical Biomechanics
2025;40(4):851-857
- CountryChina
- Language:Chinese
-
Abstract:
Objective This study quantitatively analyzed the initial displacement and stress distribution of maxillary teeth and periodontal ligaments(PDLs)under different traction positions of Class Ⅱ elastics in the anterior region of fixed multibracket appliances,aiming to provide references for the optimal application of Class Ⅱ elastics.Methods A finite element model of the maxilla with Class Ⅱ elastics was established.Based on whether tooth extraction was performed and the traction positions of Class Ⅱ elastics in the maxillary anterior region,the models were divided into 4 groups and 8 working conditions.A 1.2 N load was applied between the maxillary anterior region and the tube of the mandibular first molar.The initial displacement of maxillary teeth and the von Mises stress of maxillary PDLs were analyzed.Results The finite element model of the maxilla with Class Ⅱelastics was successfully constructed.Class Ⅱ elastics induced lingual inclination,eruption,and retraction of maxillary anterior teeth.Variations in the traction positions of Class Ⅱ elastics resulted in differences in the initial displacement of maxillary teeth and the von Mises stress of PDLs.The maximum von Mises stress of PDLs ranged from 5.8 to 12.2 kPa across all working conditions.Conclusions Different traction positions of Class Ⅱelastics alter the torque,induce distinct deformation trends in the archwire,and thus affect tooth movement.Compared with attaching Class Ⅱ elastics to the maxillary canine bracket,attaching them to the hooks increases the tendency toward deep overbite,and this tendency is more pronounced in extraction models.For patients with Class Ⅱ,Division 1 malocclusion,anterior tooth protrusion,and a tendency toward open bite,applying Class Ⅱelastics on the occlusal side of the hooks may be more beneficial in alleviating open bite and enhancing the smile arc.However,the actual efficacy requires clinical verification.
