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On-line Access: 2018-01-11

Received: 2016-12-07

Revision Accepted: 2017-02-20

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Journal of Zhejiang University SCIENCE B 2018 Vol.19 No.1 P.38-48


A finite element analysis of the stress distribution to the mandible from impact forces with various orientations of third molars

Author(s):  Yun-Feng Liu, Russell Wang, Dale A. Baur, Xian-Feng Jiang

Affiliation(s):  Key Laboratory of E&M (Zhejiang University of Technology), Ministry of Education & Zhejiang Province, Hangzhou 310014, China; more

Corresponding email(s):   liuyf76@126.com

Key Words:  Finite element analysis, Third molar, Mandible, Biomechanical simulation

Yun-Feng Liu, Russell Wang, Dale A. Baur, Xian-Feng Jiang. A finite element analysis of the stress distribution to the mandible from impact forces with various orientations of third molars[J]. Journal of Zhejiang University Science B, 2018, 19(1): 38-48.

@article{title="A finite element analysis of the stress distribution to the mandible from impact forces with various orientations of third molars",
author="Yun-Feng Liu, Russell Wang, Dale A. Baur, Xian-Feng Jiang",
journal="Journal of Zhejiang University Science B",
publisher="Zhejiang University Press & Springer",

%0 Journal Article
%T A finite element analysis of the stress distribution to the mandible from impact forces with various orientations of third molars
%A Yun-Feng Liu
%A Russell Wang
%A Dale A. Baur
%A Xian-Feng Jiang
%J Journal of Zhejiang University SCIENCE B
%V 19
%N 1
%P 38-48
%@ 1673-1581
%D 2018
%I Zhejiang University Press & Springer
%DOI 10.1631/jzus.B1600552

T1 - A finite element analysis of the stress distribution to the mandible from impact forces with various orientations of third molars
A1 - Yun-Feng Liu
A1 - Russell Wang
A1 - Dale A. Baur
A1 - Xian-Feng Jiang
J0 - Journal of Zhejiang University Science B
VL - 19
IS - 1
SP - 38
EP - 48
%@ 1673-1581
Y1 - 2018
PB - Zhejiang University Press & Springer
ER -
DOI - 10.1631/jzus.B1600552

Objective: To investigate the stress distribution to the mandible, with and without impacted third molars (IM3s) at various orientations, resulting from a 2000-Newton impact force either from the anterior midline or from the body of the mandible. Materials and methods: A 3D mandibular virtual model from a healthy dentate patient was created and the mechanical properties of the mandible were categorized to 9 levels based on the Hounsfield unit measured from computed tomography (CT) images. Von Mises stress distributions to the mandibular angle and condylar areas from static impact forces (Load I-front blow and Load II left blow) were evaluated using finite element analysis (FEA). Six groups with IM3 were included: full horizontal bony, full vertical bony, full 450 mesioangular bony, partial horizontal bony, partial vertical, and partial 450 mesioangular bony impaction, and a baseline group with no third molars. Results: Von Mises stresses in the condyle and angle areas were higher for partially than for fully impacted third molars under both loading conditions, with partial horizontal IM3 showing the highest fracture risk. Stresses were higher on the contralateral than on the ipsilateral side. Under Load II, the angle area had the highest stress for various orientations of IM3s. The condylar region had the highest stress when IM3s were absent. Conclusions: High-impact forces are more likely to cause condylar rather than angular fracture when IM3s are missing. The risk of mandibular fracture is higher for partially than fully impacted third molars, with the angulation of impaction having little effect on facture risk.


目的:评估下颌骨在具有不同形态的第三磨牙或者没有第三磨牙的情况下,当遭受到前部或侧部2000 N冲击力时,其应力分布.
方法:根据一个具有完整牙列的健康下颌骨的计算机断层扫描(CT)图像构建出其三维模型,以CT图像上的Hounsfield值(HU)为基础,计算出下颌骨的力学性能参数(包括密度和杨氏模量),共分成9组数据.构建出第三磨牙分别为水平向、垂直向以及近中方向呈45度角时的完全阻生和部分阻生的共6组下颌骨计算模型.并以无第三磨牙的下颌骨为基准模型,利用有限元方法计算在下颌前部和侧面分别受到2000 N的静态冲击力的情况下Von Mises应力分布.


Darkslateblue:Affiliate; Royal Blue:Author; Turquoise:Article


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