关键词: 漏斗状残根, 树脂水门汀, 玻璃纤维桩, 疲劳实验, 口腔修复材料　

Abstract:

BACKGROUND: Fiber post is widely used in front teeth aesthetic repair, but some defect teeth cannot form ferrule or thick root canal, which resulted in fiber post prosthetic replacement defluxion and a failure of repair. Presently, new-style resin cement had self sticking component, showing good effects in sticking of fiber post. Whether combination of new-style resin cement can repair affected teeth using fiber post deserves further investigation.
OBJECTIVE: Through fatigue test, residual flexural strength and scanning electron microscope (SEM) observation to compare the strength of severely weakened roots restored with three resin cements.
METHODS: Eighteen intact maxillary central incisors were collected and formed to severely weakened canals at the same size. Three kinds of resin cements were used to restore. Rely X Unicem, Panavia F and Super-Bond C&B resin cement and identical glass fiber post were used. All the specimens were restored using Ni-Cr ceramic crown, and placed on TCML chewing machine that loaded 1 200 000 cycle forces, and the cycle times when failure occurred were recorded. The samples were intact following loading received residual flexural strength test. SEM was employed to observe breakage surface of the samples.
RESULTS AND CONCLUSION: Mean cyclic loading was significantly greater in the Super-Bond C&B Group (1 200 000 times) than in the Relyx Unicem Group (640 000 times) and Panavia F Group (550 000 times) (P < 0.05). No significant difference was detected between the Rely X Unicem and Panavia F Groups. Residual flexural strength was 747.99 N in the Super-Bond C&B Group. SEM demonstrated that Super-Bond C&B formed longer resin processes, which were more than other two groups. Results confirmed that Super-Bond C&B demonstrated better results when restoring flared roots with prefabricated glass fiber posts.