PDF(Pubmed)
Abstract：
BACKGROUND: The fit of a metal-ceramic restoration is essential to its long-term durability. Regarding marginal and internal fit, there is not enough information about the technologies used in the production of metal-ceramic restorations. The aim of this in vitro study is to compare, both before and after porcelain firing, the marginal, axial, axio-occlusal, and occlusal fit of metal-ceramic restorations manufactured using casting, additive or subtractive computer-aided design, and computer-aided manufacturing techniques (CAD/CAM).
METHODS: CAD/CAM were used to create 50 prepared maxillary first molar-shaped Co-Cr die models, which were randomly divided into 5 groups (n = 10). Cobalt-chrome copings were produced by casting (C), hard metal milling (HM), soft metal milling (SM), selective laser melting (SLM), and selective laser sintering (SLS) techniques. Before and after porcelain firing, discrepancies of the copings were measured using the silicone replica technique. The data obtained by measurements with a stereomicroscope at x80 magnification were analyzed statistically in the SPSS program. The ROBUST three-way analysis of variance (ANOVA) method was used to compare the discrepancy values.
RESULTS: There were statistically significant differences among fabrication methods (P < .001). The HM method showed the highest discrepancy (90.1 μm), and the C (63 μm) method showed the lowest discrepancy in terms of the die model- crown fit. The C, SLS, and SM methods (63 μm; 61.6 μm; 67.7 μm) were statistically similar (P > .001). The highest discrepancy was observed on the occlusal area (87.1 μm), and the lowest discrepancy was observed on the axial area (47.7 μm) of the coping. Porcelain firing had a decrease in the discrepancy values (P = .001).
CONCLUSIONS: All CAD/CAM techniques are appropriate for clinical use; selective laser sintering and soft milling can be the more recommended methods for the compatibility of metal-porcelain restorations, as they have lower discrepancy values than the SLM and HM methods.
METHODS: CAD/CAM were used to create 50 prepared maxillary first molar-shaped Co-Cr die models, which were randomly divided into 5 groups (n = 10). Cobalt-chrome copings were produced by casting (C), hard metal milling (HM), soft metal milling (SM), selective laser melting (SLM), and selective laser sintering (SLS) techniques. Before and after porcelain firing, discrepancies of the copings were measured using the silicone replica technique. The data obtained by measurements with a stereomicroscope at x80 magnification were analyzed statistically in the SPSS program. The ROBUST three-way analysis of variance (ANOVA) method was used to compare the discrepancy values.
RESULTS: There were statistically significant differences among fabrication methods (P < .001). The HM method showed the highest discrepancy (90.1 μm), and the C (63 μm) method showed the lowest discrepancy in terms of the die model- crown fit. The C, SLS, and SM methods (63 μm; 61.6 μm; 67.7 μm) were statistically similar (P > .001). The highest discrepancy was observed on the occlusal area (87.1 μm), and the lowest discrepancy was observed on the axial area (47.7 μm) of the coping. Porcelain firing had a decrease in the discrepancy values (P = .001).
CONCLUSIONS: All CAD/CAM techniques are appropriate for clinical use; selective laser sintering and soft milling can be the more recommended methods for the compatibility of metal-porcelain restorations, as they have lower discrepancy values than the SLM and HM methods.
摘要：
背景：金属陶瓷修复体的贴合性对于其长期耐用性至关重要。关于边际和内部配合，关于金属陶瓷修复体生产中使用的技术，没有足够的信息。这项体外研究的目的是比较，瓷器烧制前后，边缘，轴向，轴咬合，以及使用铸造制造的金属陶瓷修复体的咬合配合，加法或减法计算机辅助设计，和计算机辅助制造技术(CAD/CAM)。
方法：CAD/CAM用于创建50个制备的上颌第一磨牙形Co-Cr模具模型，随机分为5组(n=10)。钴铬镀层是通过铸造(C)生产的，硬金属铣削（HM），软金属铣削（SM），选择性激光熔化（SLM），和选择性激光烧结(SLS)技术。瓷器烧制前后,使用硅胶复制技术测量了顶盖的差异。在SPSS程序中对通过用立体显微镜在X80放大倍数下测量获得的数据进行统计分析。使用ROBUST三因素方差分析(ANOVA)方法比较差异值。
结果：制造方法之间存在统计学上的显着差异（P<.001）。HM方法显示出最高的差异(90.1μm)，C（63μm）方法在模具模型-凸度拟合方面显示出最低的差异。C,SLS,和SM方法（63μm；61.6μm；67.7μm）在统计学上相似（P>.001）。在咬合区域（87.1μm）上观察到最高差异，在顶盖的轴向面积（47.7μm）上观察到最小的差异。瓷烧制的差异值降低（P=.001）。
结论：所有CAD/CAM技术都适合临床使用；选择性激光烧结和软铣削可以是更推荐的金属瓷修复体相容性方法，因为它们的差异值比SLM和HM方法低。
方法：CAD/CAM用于创建50个制备的上颌第一磨牙形Co-Cr模具模型，随机分为5组(n=10)。钴铬镀层是通过铸造(C)生产的，硬金属铣削（HM），软金属铣削（SM），选择性激光熔化（SLM），和选择性激光烧结(SLS)技术。瓷器烧制前后,使用硅胶复制技术测量了顶盖的差异。在SPSS程序中对通过用立体显微镜在X80放大倍数下测量获得的数据进行统计分析。使用ROBUST三因素方差分析(ANOVA)方法比较差异值。
结果：制造方法之间存在统计学上的显着差异（P<.001）。HM方法显示出最高的差异(90.1μm)，C（63μm）方法在模具模型-凸度拟合方面显示出最低的差异。C,SLS,和SM方法（63μm；61.6μm；67.7μm）在统计学上相似（P>.001）。在咬合区域（87.1μm）上观察到最高差异，在顶盖的轴向面积（47.7μm）上观察到最小的差异。瓷烧制的差异值降低（P=.001）。
结论：所有CAD/CAM技术都适合临床使用；选择性激光烧结和软铣削可以是更推荐的金属瓷修复体相容性方法，因为它们的差异值比SLM和HM方法低。
