金属烤瓷全冠两种颈缘设计对龈下微生物影响的研究

Influence of metal-procelain crowns with different margins on gingival sulcus microflora

目的探讨瓷颈缘与金瓷颈缘对金属烤瓷全冠龈下微生物影响有无差异。方法采用自身对照设计,双侧上颌中切牙分别采用两种颈缘设计的镍铬合金烤瓷全冠修复10例。检测修复前、修复后72h、1周、1个月和3个月全冠唇侧龈下可培养细菌总量及革兰阴性菌构成比的变化。结果两组全冠修复后72h龈下微生物总量减少,1周、1个月和3个月递增。革兰阴性菌构成比在72h、1周、1个月递增,3个月和1个月无显著差异。各时间点两组修复体龈下可培养细菌总量及革兰阴性菌构成比无显著差异。结论瓷颈缘与传统金瓷颈缘对龈下微生物的影响没有显著差异,两者都会导致龈下微生物总量及革兰阴性菌增加。

Objective To study the changes in microecology in gingival sulcus of abutment teeth after restored by PFM（porcelain-fused-tometal） crowns with pocelain margin and metal-pocelain margin.Melhods Ten patients who were ready to accept PFM crowns in their maxillary central incisors of both sides were selected. One side of the incisor used PFM crowns with pocelain margin and the other with metal-pocelain margin. Then at the following five time points：before tooth preparation, 72 h, lweek, 1 month and 3 months after restoration of crowns, the total cultivable flora and the constituent ratio of the gram negative bacteria were counted. Results The total number of germs detected in gingival sulcus decreased significantly 72h after restoration, while it increased steadily after lweek, 1 month and 3 months of restoration. The constituent ratio of gram negative bacteria increased steadily within 1 month,while there was no difference between 1 month and 3 months.There were no significant differences in total numbers of germs and constituent ratio of gram negative bacteria between the two groups. Conclusion Restoration of two kinds of PFM crowns enhanced the accumulation of the total cultivable flora and gram negative bacteria in gingival suleas of abutment teeth, while there was no difference in total germs and gram negative bacteria.