基底冠形态设计对氧化锆全冠抗折强度的影响

Influence of Framework Design on Fracture Strength of Zirconia Crown

目的:探讨不同基底冠设计对氧化锆全冠抗折强度的影响,以探索最佳的基底冠设计来提高氧化锆全冠的抗折性能。方法:设计并制作4组不同颈环高度的氧化锆冠,分别为:A组0.00 mm、B组1.00 mm、C组2.00mm、D组颈环最高点为外形高点位置,每组7颗,万能试验机测试其断裂载荷,体式显微镜及扫描电子显微镜观察破损形态。结果:A、B、C、D四组断裂载荷均值分别为1.56KN、1.83KN、1.95KN、2.27KN,4组断裂载荷差异具有统计学意义,A、D组间差异具有统计学意义,其余组间差异无统计学意义。氧化锆全瓷冠破损方式为崩瓷及脱瓷,四组破损方式的构成比的差异无统计学意义。结论:基底冠的形态设计可以影响氧化锆全冠的抗折强度,且随着颈环高度的增加抗压强度呈增大趋势。

Objective：To explore the optimal design of the framework so that to improve the fracture strength of the zirconia crown.Methods：Four different framework designs based on the thickness of zirconia cervical collar were used：0.00 mm zirconia collar（Group A）,1.00 mm（Group B）,2.00 mm（Group C）,and height of contour（Group D）.There were 7 samples in each group.The universal test machine was used to test the fracture load.The damage shape was observed by the body type microscope and scanning electron micrographs.Results：Mean of fracture loads were 1.56 KN for Group A,1.83 KN for Group B,1.95 KN for Group C,and 2.27 KN for Group D.The fracture load of four groups showed a significant difference.Group A was significantly different from Group D.Damage shapes were crack and chipping.There was no significant difference in the composition ratio between four sets of damage shapes.Conclusion：The framework design can affect the fracture strength of the zirconia crown,and the more thick of zirconia collar,the higher fracture strength of zirconia crown.