关键词: 烤瓷熔附金属冠, 冠颈缘位置, 龈沟液, 内毒素, 天冬氨酸基转移酶

Abstract:

Objective This study aims to investigate the effect of the marginal position of porcelain-fused-to-metal(PFM) crown on periodontal health. Methods Sixty patients who needed PFM crown for the mandibular first molar were randomly divided into two groups of 30 patients each according to the difference in the marginal position of the crown. Group A comprised patients with crown margins under the gingival level, whereas Group B was composed of patients with crown margin at the gingival level. Gingival crevicular fluid(GCF) were collected at four time points, namely, before crown cementation and at 1, 3, and 6 months after crown cementation. GCF volume, endotoxin levels, and aspartate transaminase(AST) were detected using an automated chemical analyzer. The differences among the variations between pre- and post-crown cementation and between the two groups were analyzed. Results GCF volume, endotoxin levels, and AST in Group A increased at 1, 3, and 6 months after cementation compared with that before crown cementation(P<0.05). In Group B, the GCF volume, endotoxin levels, and AST remained stable and did not exhibit any changes(P>0.05). Significant statistical differences were found between the means of variation of Groups A and B at 1, 3, and 6 months after cementation(P<0.05). Conclusion Based on the results of this study, the PFM crown with gingival margin at gingival level is better than that under gingival level in terms of its benefit to periodontal health.

Key words: porcelain-fused-to-metal crown, crown margin, gingival crevicular fluid, endotoxin, aspartate transaminase