3种不同金属烤瓷冠适合性的对照研究

An experimental study on the adaptation of three kinds of porcelain fused-to-metal restorations

目的对镍铬合金烤瓷冠、贵金属合金烤瓷冠和金沉积烤瓷冠的边缘适合性进行研究,为临床应用提供一定的理论依据和指导。方法分别制作镍铬合金烤瓷冠、贵金属合金烤瓷冠和金沉积烤瓷冠各8个,将3种烤瓷冠在无水酒精中超声清洁5min,用聚羧酸锌黏固剂按编号将全冠黏固于各自的塑料代型上,指压就位维持10min。将黏有冠的塑料代型用自凝塑料包埋制成小方块,用金刚砂片切机沿代型底座唇舌向直径纵剖,抛光后备测。在扫描电镜下,放大120～200倍观察冠组织面与代型粘接面间的黏固剂厚度。结果金沉积烤瓷冠与贵金属合金烤瓷冠的整体黏固剂厚度无统计学差异(P>0.05),但二者均与镍铬合金烤瓷冠的整体黏固剂厚度有统计学差异(P<0.05)。结论金沉积烤瓷冠与贵金属合金烤瓷冠的边缘适合性优于镍铬合金烤瓷冠。

Objective To compare the adaptation of porcelain fused-to-metal （PFM） restorations made from Ni-Cr alloy, precious alloy and galvanized forming copings after cementation and to provide a theory guidance for their application. Methods Three kinds of crowns （Ni-Cr alloy, precious alloy and galvanized forming） were manufactured and cleaned by ultrasonic vibrate with alcoholic solution for 5 minutes, and cemented on their dies as their order. All the crowns were cemented by polycarboxylate zinc-cement and maintained 10 minutes. After coated in the center of methyl acrylic resins, all the samples were cut vertically along buccolingual direction. The cement thickness of PFM was measured by scanning electron microscope and the data were analyzed by multivariate ANOVA. Results No significant difference was found between the cement thickness of precious alloy crown and galvanized forming crown （P〉 0.05）, while both of these two kinds of crown had significant differences in cement thickness with Ni-Cr crown （P〈 0.05）. Conclusion The adaptation of precious alloy crown and galvanized forming crown are superior to Ni-Cr crown.