Chu C H, King N M, Lee A M, Yiu C K, Wei S H
University Health Service, University of Hong Kong, Hong Kong.
Quintessence Int. 1996 Jul;27(7):493-501.
This study investigated changes in the marginal adaptation and surface morphology of Ketac-Silver and Chelon-Silver glass-current cements over time. Dispersalloy amalgam was used as a control. Contralateral pairs of carious primary molars were restored with the test materials and amalgam. Clinical evaluations were scheduled at 12, 18, and 24 months after placement. Gold-plated replicas of the restorations were observed with scanning electron microscopy. Fractures and cracks in the surface of the Dispersalloy and Chelon-Silver increased the surface roughness; however, the damage was superficial and self-limiting in the Dispersalloy restorations, while in Chelon-Silver the fractures caused the material to break down in layers. A substantial quantity of pores, usually smaller than 50 microns in diameter, were observed throughout the surface of the Chelon-Silver restorations. The pores in the surface of Ketac-Silver were fewer and smaller. The incidence of cavomarginal breakdown increased with time. Chelon-Silver restorations had a higher rate of cavomarginal breakdown than did Ketac-Silver and Dispersalloy restorations up to 18 months. However, there was no statistically significant difference in the marginal adaptation of the three groups at 24 months.
本研究调查了Ketac - Silver和Chelon - Silver玻璃离子水门汀的边缘适应性和表面形态随时间的变化。采用Dispersalloy银汞合金作为对照。用受试材料和银汞合金修复对侧的龋损乳磨牙。在修复体放置后12、18和24个月进行临床评估。用扫描电子显微镜观察修复体的镀金复制品。Dispersalloy和Chelon - Silver表面的断裂和裂纹增加了表面粗糙度；然而，Dispersalloy修复体中的损伤是表面性的且具有自限性，而Chelon - Silver中的断裂导致材料分层崩解。在Chelon - Silver修复体的整个表面观察到大量通常直径小于50微米的孔隙。Ketac - Silver表面的孔隙较少且较小。洞缘破坏的发生率随时间增加。在18个月时，Chelon - Silver修复体的洞缘破坏率高于Ketac - Silver和Dispersalloy修复体。然而，24个月时三组的边缘适应性无统计学显著差异。
