Three-dimensional finite element analysis of capabilities of a new open “C”-shaped molar band with nanocoating

doi:10.3969/j.issn.2095-4344.2014.39.009

Abstract

Abstract:

BACKGROUND: A new open “C”-shaped molar band with nanocoating (patent number: ZL201110057699.1) has been invented to overcome some weakness of traditional bands and buccal tubes, which is used for molar fixation.
OBJECTIVE: Using three-dimension finite element analysis software to theoretically prove that the new band comes up to clinic requirement.
METHODS: We established a finite element model of alveolar bone-tooth-band, and node domains tensile and shear loading were given. Stress distribution of the new bands through numerical simulation was predicted and calculated. Simulation of 20 N orthodontic force was applied in medial direction, distal direction and vertical direction in the three-dimensional model of a new band buccal tube and traditional band, to analyze the stress state in different directions under the force of the binder.
RESULTS AND CONCLUSION: By numerical simulation of three-dimensional finite element, the stress of the new band was higher than that of the traditional band, but it could not reach the clinical cracking limit of resin reinforced glass ionomer cement. So the new band could theoretically satisfy the clinical requirements.

中国组织工程研究杂志出版内容重点：生物材料；骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性；组织工程

全文链接：

Key words: orthodontic anchorage procedures, dental stress analysis, finite element analysis

CLC Number:

R318

Zhou Shan, Wang Xiang, Xu Xu-guang, Lu Xiao-li. Three-dimensional finite element analysis of capabilities of a new open “C”-shaped molar band with nanocoating[J]. Chinese Journal of Tissue Engineering Research, 2014, 18(39): 6282-6286.

Figures/Tables 1

2.1 近中方向断裂过程数值模拟在近中方向载荷20 N的作用下，在颊面管与带环过渡位置产生最大拉应力达到26.2 MPa，牙齿与牙槽骨交界处的拉应力达到4.1 MPa。整个界面单元在颊侧受到剪切作用，在颊面管两侧的对应位置出现拉应力，与实际情况一致。最大von-Mises应力为1.44 MPa，其中法向应力为0.8 MPa，切向力分别为 0.59 MPa和0.68 MPa。根据界面单元的应力平方开裂准则，其应力状态并未达到RMGIC黏结剂的开裂水平，这表明在20 N拉力的作用下，黏结单元不会产生破坏，从理论上证明三面带环与RMGIC组合满足口腔正畸的使用要求。 2.2 远中方向断裂过程数值模拟在远中方向载荷20 N的作用下，在颊面管与带环过渡位置产生最大拉应力达到26.2 MPa，牙齿与牙槽骨交界处的拉应力达到4.1 MPa，与近中方向载荷20 N产生的应力状态相当。整个界面单元在颊侧受到剪切作用，最大von-Mises应力为1.44 MPa，其中法向应力为0.98 MPa。由于三面带环在近中侧面缺少约束，与近中方向0.8 MPa相比，界面单元的法向拉应力更大。切向力分别为0.76 MPa和 0.54 MPa，应力状态并未达到RMGIC黏结剂的开裂水平，这表明在20 N拉力的作用下，黏结单元同样没有产生破坏。 2.3 垂直方向断裂过程数值模拟在垂直方向上施加 20 N载荷，在颊面管与带环过渡位置产生最大拉应力达到36.4 MPa，牙齿与牙槽骨交界处的拉应力达到4.1 MPa。整个界面单元在颊侧受到剪切作用，最大von-Mises应力为2.6 MPa，其中界面单元在颊面管下部对应位置产生最大法向拉应力为1.75 MPa，大于近中、远中方向同样的载荷值引起的法向应力0.8，0.98 MPa，这是由于带环在垂直方向的宽度为4 mm，横向的扭转刚度弱于垂向的扭转刚度。切向应力分别为0.88 MPa和1.25 MPa，综合起来，根据界面单元的开裂准则，并未达到RMGIC黏结剂的开裂水平，这表明在20 N拉力的作用下，黏结单元同样没有产生破坏。"

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