桩核材料与纤维/树脂复合材料桩钉联合修复无髓牙的抗折性能研究

目的评价3种树脂类桩核材料与高强玻璃纤维/树脂复合材料(FRC)桩钉联合修复无髓牙的抗折性能。方法用FRC桩钉和3种经不同方法处理(热压和未热压)的树脂核(Artglass聚合体、Charisma复合树脂、AB组份复合树脂)联合修复离体无髓牙根,测试1300加载时的破坏载荷。结果Artglass聚合体组的抗折力最高(505.4N),经热压处理后强度明显提高(564.1N) ; Chari~复合树脂组经热压后脆性增加,强度降低(热压前后分别为411.3N和 315.3N); AB组份树脂组经热压后强度明显提高(热压前后分别为358.4N和423.4N)。实验中无1例出现桩钉折断和聚酷冠碎裂。结论不同桩核材料与FRC桩钉联合修复无髓牙的抗折力不同,其中Art乡ass聚合体组的抗折力最高,但是此3组的抗折力均超过了咀嚼过程中前牙的咬合力,树脂核与纤维/树脂复合材料桩钉联合修复无髓前牙残根可以满足临床需要。

Comparison of Fracture Resistance of Pulpless Teeth Restored with Fiber Reinforced Composite Posts and three Kinds of Resin Core Material

OBJECTIVE: To compare the fracture resistances of pulpless teeth restored with FRC (Fiber Reinforced Composite) posts and three kinds of resin core material. METHODS: A total of 42 recently extracted upper incisors were randomly divided into 3 groups. Group A was restored with prefabricated glass-fiber posts and Artglass polymer core; group B with prefabricated glass-fiber posts and Charisma composite resin core; and group C with prefabricated glass-fiber posts and AB composite resin core. In every group, the core material was processed by hot-press and non hot-press respectively. The posts size and shape were identical in the 3 groups. All teeth were fully covered with polycarbonate resin crowns. Fracture resistance was measured by applying point force at 130 degrees to the long axis of the teeth on an universal testing machine. RESULTS: Mean fracture threshold was 505.4 N +/- 42.0 N and 564.1 N +/- 41.7 N in group A, 411.3 N +/- 23.3 N and 315.3 N +/- 19.1 N in group B and 358.4 N +/- 36.1 N and 423.4 N +/- 47.5 N in group C. In all groups, there was no posts fracture and polycarbonate resin crowns fragmentation. CONCLUSION: The composite restoration of FRC posts combined with resin core and resin crown can improve the fracture resistance of the pulpless roots. The strength of resin core material can be increased by hot-press methods.