Rismanchian Mansoor, Dakhilalian Mansour, Bajoghli Farshad, Ghasemi Ehsan, Sadr-Eshkevari Pooyan
Department of Fixed Prosthodontics, Torabinejad Research Center, School of Dental Medicine, Isfahan University of Medical Sciences (MUI), Isfahan, Iran.
J Oral Implantol. 2012 Apr;38(2):133-9. doi: 10.1563/AAID-JOI-D-09-00037.1. Epub 2010 Jun 14.
Proper stress distribution on dental implants is necessary in bar-retained implant overlay dentures. We aimed to comparatively assess this stress distribution according to different bar heights using finite element models. A three-dimensional (3D) computer model of mandible with 2 implants (ITI, 4.1 mm diameter and 12 mm length) in canine areas and an overlying implant-supported bar-retained overlay denture were simulated with 0-, 1-, 2-, and 3-mm bar heights using ABAQUS software. A vertical force was applied to the left first molar and gradually increased from 0 to 50 N. The resultant stress distribution was evaluated. Bars of 1 and 2 mm in height transferred the least stress to the implants (3.882 and 3.896 MPa, respectively). The 0-mm height of the bar connection transferred the highest stress value (4.277 MPa). The amount of stress transferred by 3-mm heights of the bar connection was greater than that of 1- and 2-mm bar connections and smaller than that of 0-mm bar connection (4.165 kgN). This 3D finite element analysis study suggested that the use of Dolder bar attachment with 1- and 2-mm heights could be associated with appropriate stress distribution for implant-retained overlay dentures.
在杆卡式种植覆盖义齿中，牙种植体上的应力分布恰当很有必要。我们旨在使用有限元模型，根据不同的杆高度对这种应力分布进行比较评估。使用ABAQUS软件，模拟了一个在下颌犬牙区域有2颗种植体（ITI，直径4.1毫米，长度12毫米）的三维（3D）计算机模型，以及一个覆盖其上的种植体支持的杆卡式覆盖义齿，杆高度分别为0、1、2和3毫米。对左侧第一磨牙施加垂直力，并从0逐渐增加到50牛。评估由此产生的应力分布。高度为1毫米和2毫米的杆向种植体传递的应力最小（分别为3.882和3.896兆帕）。杆连接高度为0毫米时传递的应力值最高（4.277兆帕）。杆连接高度为3毫米时传递的应力量大于1毫米和2毫米杆连接的情况，小于0毫米杆连接的情况（4.165千牛）。这项三维有限元分析研究表明，使用高度为1毫米和2毫米的Dolder杆附着体可能与种植体支持的覆盖义齿的适当应力分布相关。
