Department of Dental Materials and Prosthodontics, Dental School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.
J Adv Prosthodont. 2012 May;4(2):89-92. doi: 10.4047/jap.2012.4.2.89. Epub 2012 May 30.
Adequate passive-fitting of one-piece cast 3-element implant-supported frameworks is hard to achieve. This short communication aims to present an alternative method for section of one-piece cast frameworks and for casting implant-supported frameworks.
Three-unit implant-supported nickel-chromium (Ni-Cr) frameworks were tested for vertical misfit (n = 6). The frameworks were cast as one-piece (Group A) and later transversally sectioned through a diagonal axis (Group B) and compared to frameworks that were cast diagonally separated (Group C). All separated frameworks were laser welded. Only one side of the frameworks was screwed.
The results on the tightened side were significantly lower in Group C (6.43 ± 3.24 µm) when compared to Groups A (16.50 ± 7.55 µm) and B (16.27 ± 1.71 µm) (P<.05). On the opposite side, the diagonal section of the one-piece castings for laser welding showed significant improvement in the levels of misfit of the frameworks (Group A, 58.66±14.30 µm; Group B, 39.48±12.03 µm; Group C, 23.13±8.24 µm) (P<.05).
Casting diagonally sectioned frameworks lowers the misfit levels. Lower misfit levels for the frameworks can be achieved by diagonally sectioning one-piece frameworks.
很难实现单部件铸造三元件种植体支持框架的充分被动适配。本简短交流旨在介绍一种用于单部件铸造框架分段和铸造种植体支持框架的替代方法。
测试了三个单位种植体支持的镍铬(Ni-Cr)框架的垂直不匹配(n = 6)。将框架作为一个整体铸造(A 组),然后通过对角线轴横向分段(B 组),并与对角分离铸造的框架(C 组)进行比较。所有分离的框架都经过激光焊接。仅框架的一侧拧入螺丝。
在拧紧侧,C 组(6.43 ± 3.24 µm)的结果明显低于 A 组(16.50 ± 7.55 µm)和 B 组(16.27 ± 1.71 µm)(P<.05)。在相反的一侧,用于激光焊接的单件铸造的对角线分段显示出框架不匹配水平的显著改善(A 组,58.66±14.30 µm;B 组,39.48±12.03 µm;C 组,23.13±8.24 µm)(P<.05)。
铸造对角分段框架可降低不匹配水平。通过对角分段单部件框架可以实现框架不匹配水平的降低。