Gu Xin-Hua, Kern Matthias
Department of Stomatology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People's Republic of China.
Int J Prosthodont. 2003 Mar-Apr;16(2):109-16.
This study evaluated the marginal discrepancies and leakage of all-ceramic crowns cemented with different luting agents after fatigue tests.
Forty-eight all-ceramic crowns were cemented onto natural molars. Zinc-phosphate cement, compomer cement, and an adhesive composite resin luting system were used in 16 specimens each. Sixteen metal-ceramic crowns were cemented with zinc-phosphate cement as a control. Half of the specimens in each group were fatigued in a chewing simulator for 600,000 loading cycles with 3,500 thermocycles. The others received the 3,500 thermocycles only. An impression-replica technique and SEM were used for evaluation of the marginal discrepancies. Leakage of the specimens was microscopically assessed.
There were no significant differences between marginal discrepancies of the groups, with the exception of porcelain shoulder margins in the metal-ceramic group, which had significantly larger discrepancies (P < .01). There was no significant effect of the fatigue tests on marginal discrepancies. However, significant differences of leakage were found between the groups cemented with the different luting agents after both fatigue tests. The adhesive composite resin luting system demonstrated the least leakage. The compomer cement showed an intermediate level of leakage, and the zinc-phosphate cement showed severe leakage that extended through the dentinal tubules to the pulp chambers. No significantly different effect of the two fatigue tests on the leakage was found.
The adhesive composite resin luting system showed clinically acceptable marginal discrepancies and an excellent ability to minimize leakage of all-ceramic crowns.
本研究评估了在疲劳试验后，用不同粘结剂粘结的全瓷冠的边缘差异和边缘渗漏情况。
将48个全瓷冠粘结到天然磨牙上。每组16个样本，分别使用磷酸锌水门汀、复合树脂粘结剂和一种粘结性复合树脂粘结系统。另外粘结16个金属烤瓷冠作为对照组，使用磷酸锌水门汀。每组样本的一半在咀嚼模拟器中进行600,000次加载循环并伴有3500次热循环疲劳试验。另一半仅进行3500次热循环。采用印模复制技术和扫描电子显微镜评估边缘差异。通过显微镜评估样本的边缘渗漏情况。
除金属烤瓷组的瓷肩边缘差异显著更大（P <.01）外，各组之间的边缘差异无显著差异。疲劳试验对边缘差异无显著影响。然而，在两种疲劳试验后，使用不同粘结剂粘结的各组之间边缘渗漏存在显著差异。粘结性复合树脂粘结系统的边缘渗漏最少。复合树脂粘结剂的边缘渗漏处于中等水平，而磷酸锌水门汀显示出严重的边缘渗漏，渗漏延伸至牙本质小管并进入髓腔。两种疲劳试验对边缘渗漏的影响无显著差异。
粘结性复合树脂粘结系统在临床上具有可接受的边缘差异，并且在最小化全瓷冠边缘渗漏方面具有出色的能力。
