Stresses and deflections in the floor of model cavity preparations.
Stresses and deflections in the floor of model cavity preparations.
复制标题
模型空腔制备地板的应力和变形。
DOI：
10.1111/j.1365-2842.1974.tb00777.x
复制
发表时间：
1974
影响因子：
2.9
通讯作者：
R. G. Craig
中科院分区：
文献类型：
--
作者：
J. W. Farah;J. Hood;R. G. Craig
总结
在这项研究中，有限元法结合一个理想化的第一磨牙的轴对称模型，以确定应力，以及在地板上的圆柱形腔制备所造成的各种尺寸的冷凝器的偏转。
发现对于0·25 mm厚度的牙本质、2 mm冷凝器和2 kg载荷，在制备物中心附近获得约70 MN/m2的拉伸应力。在相同载荷和4 mm冷凝器下，获得的拉应力仅为42 MN/m2。Bowen & Rodriguez（1962）和Lehman（1967）报道牙本质的抗张强度分别为51.7 MN/m2和41.5 MN/m2。因此，证明了对于载荷、冷凝器尺寸和腔体尺寸的某些组合，可能超过腔体底部中的牙本质的拉伸强度，并且可能导致腔体底部失效。
Summary
In this study the finite element method was used in conjunction with an axisymmetric model of an idealized first molar to determine the stresses, as well as deflections in the floor of a cylindrical cavity preparation as caused by condensers of various sizes.
It was found that for the 0·25 mm thickness of dentine, the 2 mm condenser and a 2 kg load, a tensile stress of approximately 70 MN/m2 was obtained near the centre of the preparation. Under the same load and a 4 mm condenser a tensile stress of only 42 MN/m2 was obtained. Bowen & Rodriguez (1962) and Lehman (1967) reported that the tensile strength of dentine was in the order of 51.7 MN/m2 and 41.5 MN/m2 respectively. Thus it was demonstrated that for certain combinations of load, condenser size, and cavity dimensions, the tensile strength of the dentine in the cavity floor could be exceeded and failure of the cavity floor could ensue.