Osman Saad A, McCabe John F, Walls A W G
Dental School, University of Newcastle upon Tyne, UK.
Eur J Prosthodont Restor Dent. 2006 Mar;14(1):23-7.
The film thickness and rheological properties [viscosity and tan sigma], of different resin based crown and bridge luting agents, including Panavia 21, Superbond, All Bond C&B Cement, Variolink were compared with zinc phosphate cement. A modification of the method in ISO 9917 (1991) and a controlled stress rheometer were used to monitor the changes in the film thickness and rheological properties respectively. For each material, the film thickness and rheological characteristics were determined at 60s after start of mixing and then made at regular intervals until immediately before the material was set. For the initial film thickness, the difference among the values for Varionk, Superbond and zinc phosphate cement was not significant (P>0.05), and less than 25microm. The values for All Bond C&B Cement and Panavia 21 were at least twice that of the other materials tested. All Bond C&B Cement produced the highest film thickness value at both the initial period and at 240s. Regarding viscosity, Superbond had the lowest initial value but the highest value at 240s. Variolink gave the highest initial value of viscosity, but the differences in the initial values among the other materials were small. During the whole period of testing, zinc phosphate cement gave the highest values of tan sigma, and Panavia 21 showed no significant change in any of the measured properties. The methods were able to distinguish the behaviour of different cement materials. Some resin cements produce larger than optimal values of film thickness and in some cases this is related to a rapid increase in viscosity after mixing. It is expected that differences in the ability of cements to form thin films will affect the seating of cemented restorations.
对不同树脂基冠桥粘结剂（包括帕纳维亚21、超级粘结剂、全粘结C&B水门汀、Variolink）的薄膜厚度和流变特性（粘度和损耗因子）与磷酸锌水门汀进行了比较。采用ISO 9917（1991）方法的一种改进方法，并使用控制应力流变仪分别监测薄膜厚度和流变特性的变化。对于每种材料，在混合开始后60秒测定薄膜厚度和流变特性，然后定期进行测定，直到材料即将凝固。对于初始薄膜厚度，Variolink、超级粘结剂和磷酸锌水门汀的值之间差异不显著（P>0.05），且小于25微米。全粘结C&B水门汀和帕纳维亚21的值至少是其他测试材料的两倍。全粘结C&B水门汀在初始阶段和240秒时产生的薄膜厚度值最高。关于粘度，超级粘结剂的初始值最低，但在240秒时最高。Variolink的粘度初始值最高，但其他材料的初始值差异较小。在整个测试期间，磷酸锌水门汀的损耗因子值最高，帕纳维亚21在任何测量特性方面均无显著变化。这些方法能够区分不同水门汀材料的性能。一些树脂水门汀产生的薄膜厚度值大于最佳值，在某些情况下，这与混合后粘度的快速增加有关。预计水门汀形成薄膜能力的差异将影响粘结修复体的就位。
