Kern M, Thompson V P
Department of Restorative Dentistry, Dental School, University of Maryland, Baltimore.
J Dent. 1995 Feb;23(1):47-54. doi: 10.1016/0300-5712(95)90660-a.
Common nickel-chromium-beryllium alloys used for resin-bonded fixed partial dentures have possible health hazards due to leaching of nickel and beryllium. For resin-bonded restorations corrosion resistant cobalt-chromium alloys (CoCr) are a suitable alternative material without sacrificing physical properties. This study evaluated the bond strength and bond durability of new adhesive systems to a CoCr alloy. Plexiglas (acrylic) tubes filled with composite were bonded to CoCr alloy discs. Groups of 24 samples were bonded using six different bonding systems. Subgroups of eight bonded samples were stored in an isotonic artificial saliva solution (37 degrees C) either for 1 day, 30 days or 150 days. In addition the 30- and 150-days samples were subjected to 7500 or 37,500 thermal cycles, respectively. The bond strength of a conventional BisGMA composite (Twinlook) to sandblasted CoCr was significant lower than when using chemomechanical bonding systems and decreased continuously during the storage time of 150 days. The additional use of silane on the sandblasted alloy resulted in an insignificant increase in bond strength. Statistically significant higher and more durable bonds to CoCr alloy were achieved either with the combination of silica coating and use of the conventional BisGMA composite or with the combination of sandblasting and the use of a composite modified with a phosphate monomer (Panavia EX). In the latter systems, the bond strengths were mainly limited by the cohesive strength of the resin composites: partial adhesive failures were only observed for a tribochemical silica coating system. A new composite also containing the active phosphate monomer (Panavia TPN-S) exhibited a significant decrease in cohesive strength over time.
用于树脂粘结固定局部义齿的常见镍铬铍合金，因镍和铍的浸出可能存在健康危害。对于树脂粘结修复体，耐腐蚀钴铬合金（CoCr）是一种合适的替代材料，且不会牺牲物理性能。本研究评估了新型粘结系统与CoCr合金的粘结强度和粘结耐久性。将填充有复合材料的有机玻璃（丙烯酸）管粘结到CoCr合金圆盘上。使用六种不同的粘结系统粘结24个样本组成的组。将每组八个粘结样本的亚组分别在等渗人工唾液溶液（37℃）中储存1天、30天或150天。此外，30天和150天的样本分别经受7500次或37500次热循环。传统双甲基丙烯酸缩水甘油酯（BisGMA）复合材料（Twinlook）与喷砂处理的CoCr合金的粘结强度显著低于使用化学机械粘结系统时，并且在150天的储存时间内持续下降。在喷砂处理的合金上额外使用硅烷，粘结强度增加不显著。通过二氧化硅涂层与传统BisGMA复合材料结合使用，或通过喷砂处理与使用含磷酸盐单体改性的复合材料（Panavia EX）结合，可实现与CoCr合金的粘结强度在统计学上显著更高且更持久。在后者系统中，粘结强度主要受树脂复合材料的内聚强度限制：仅在摩擦化学二氧化硅涂层系统中观察到部分粘结失败。一种同样含有活性磷酸盐单体的新型复合材料（Panavia TPN-S），其内聚强度随时间显著下降。
