调整氧化铝内冠轴壁聚合度对全瓷冠强度的影响

Effect of Adjusting Polymerization Degree of Axial Wall of Alumina Inner Crown on Compression Strength of All-ceramic Crowns

目的探讨在全瓷冠基牙预备轴壁聚合度偏大的情况下,调整氧化铝内冠轴壁聚合度对全瓷冠抗压强度的影响。方法将离体的上颌左中切牙制备成轴壁内聚12°的基牙预备体,并制作A、B、C组轴壁聚合度(4°、8°、12°)的氧化铝内冠。内冠上堆筑饰面瓷恢复牙冠形态,通过加载实验测试其抗压强度。结果 A组抗压强度最高,A、B组间无统计学意义(P>0.05),A、C组间及B、C组间有统计学意义(P<0.05)。结论基牙轴壁聚合度偏大可适当调整氧化铝内冠聚合度提高全瓷冠的抗压强度。

Objective To discuss the effect of adjusting the polymerization degree of axial wall of alumina inner crown on the compression strength of all-ceramic crowns in the all-ceramic crown abutment preparation shaft wall case of larger degree of polymerization.Methods Use the maxillary second premolars in vitro to manufacture the base tooth preparation,whose cohesive angle was 12°at the axial surface,and produced group A、B and C of alumina inner crown of different convergence angles（4°,8° and 12°）.The shape of dental crown was recovered by building veneering porcelain at the inner crown,whose compression strength was tested by loading experiment.Results The compression strength of group A was the highest in 3 groups.There was no significantly difference between group A and group B（P〈0.05）.There were significantly differences between group A and group C,group B and group C（P〈0.05）.Conclusion For these all-ceramic abutment crowns,whose polymerization degree of axial wall is a little larger,appropriate adjustments of polymerization degree of alumina inner crown can effectively improve the strength of all-ceramic crowns.