Abstract: Objective    To evaluate the influence of silver-palladium alloy as the materials of inner crown in subgingival and subgingival shoudler design on periodontal tissue after repairing. Methods    A total of 83 clinical diseased teeth were chosen in this study. Totally 39 teeth were repaired with silver-palladium alloy porcelain crown in subgingival shoulder design，and the other 44 were repaired with silver-palladium alloy porcelain crown in supergingival shoulder design. Follow-up visits were performed at 6 months and 12 months after operation. The changes of periodontal sulcus bleeding index and weight of gingival crevicular fluid （GCF） were observed. IL-1β，TNF and the positive rates of Pg，Aa，Tf，Fn and Pi by PCR in GCF were detected. Results    In the silver-palladium alloy porcelain crown group in subgingival shoulder design，there were significant differences in periodontal sulcus bleeding index and the weight of GCF between pre- and the 12th month post-restoration（P < 0.05），while there was no significant difference in IL-1β，TNF and the positive rates of Pg，Aa，Tf，Fn and Pi by PCR in GCF between pre- and the 12th month post-restoration（P > 0.05）. In the silver-palladium alloy porcelain crown group in supergingival shoulder design.，there was no significant difference in periodontal sulcus bleeding index，the weight of GCF，IL-1β，TNF and the positive rates of Pg，Aa，Tf，Fn and Pi by PCR in GCF between pre- and 12th post-restoration（P > 0.05）. Conclusion    Silver-palladium alloy is an ideal substrate material of porcelain fused to metal crown. The silver-palladium alloy porcelain crown in subgingival shoudler may have an potential adverse effect on periodontal tissue to a certain degree compared with that in supergingival shoulder design.

Key words: porcelain fused to metal crown, silver-palladium alloy, periodontal index, periodontopathic bacteria, gingival crevicular fluid, shoulder design

摘要： 目的    评价龈上及龈下肩台设计的银钯合金烤瓷冠修复对牙周组织的影响。方法    选择2009年4月至2011年10月来解放军第202医院口腔科采用银钯合金烤瓷全冠进行修复的患者39例（共83颗患牙），其中龈下肩台设计39颗，龈上肩台设计44颗。比较修复前和修复后6、12个月患牙龈沟出血指数（SBI）、龈沟液（GCF）量、GCF中IL-1β和TNF-α含量，以及龈下菌斑中牙龈卟啉单胞菌（Pg）、伴放线嗜血杆菌（Aa）、福赛斯坦纳菌（Tf）、具核梭杆菌（Fn）、中间普氏菌（Pi）等5种细菌检出率。结果    银钯合金烤瓷冠修复后12个月，龈下肩台设计的患牙SBI和GCF量与修复前比较差异具有统计学意义（P < 0.05），龈上和龈下肩台设计的患牙GCF中IL-1β、TNF-α含量及可疑致病菌检出率各时间点间差异均无统计学意义（P > 0.05）。 结论    银钯合金是较为理想的金属烤瓷冠材料，但龈下肩台较龈上肩台设计的修复体对牙周组织可能存在潜在的负面影响。

关键词: 金属烤瓷冠, 银钯合金, 牙周指数, 牙周致病菌, 龈沟液, 肩台设计