Blackman R, Baez R, Barghi N
Department of Restorative Dentistre, University of Texas Health Science Center, Dental School, San Antonio.
J Prosthet Dent. 1992 Apr;67(4):435-40. doi: 10.1016/0022-3913(92)90068-l.
The biocompatibility of titanium with human tissue is well established; its potential as an alternate metal for crown restorations has yet to be fully investigated. This study measured the geometry and accuracy of coping margins cast in Ti, 99.5% chemically pure. Twenty castings with 45-degree facial and 90-degree palatal margins were made by indirect technique with a commercial system using recommended procedures. They were then cemented with ZnPO4 cement. The coping and die assemblies were embedded in resin, sectioned longitudinally, and measured with a microscope at x50 power. Casting shrinkage was characteristic, particularly along the horizontal axis in the plane of the shoulder. Although horizontal linear shrinkage of 45-degree margins was greater than that for the 90-degree form, the surface of marginal discrepancy was greatest with the 90-degree configuration.
钛与人体组织的生物相容性已得到充分证实；其作为牙冠修复替代金属的潜力尚未得到充分研究。本研究测量了用99.5%化学纯钛铸造的基底冠边缘的几何形状和精度。采用商业系统，按照推荐程序，通过间接技术制作了20个面部边缘为45度、腭部边缘为90度的铸件。然后用磷酸锌水门汀粘结。将基底冠和代型组件嵌入树脂中，纵向切片，并用50倍显微镜测量。铸造收缩具有特征性，尤其是在肩部平面的水平轴上。尽管45度边缘的水平线性收缩大于90度形状的，但边缘差异表面在90度构型时最大。
