不同铸造合金对铸造冠边缘适合性影响的实验研究

目的观察Dentaurum包埋材料与3种牙科合金匹配对铸造冠边缘适合性的影响。方法制作模拟后牙全冠外形的标准帽状试件及圆管,于试件上制作30个熔模,随机分为3组,每组按照Dentaurum包埋材料的使用说明进行有圈包埋,分别采用3种合金进行铸造。铸造冠在原标准帽状试件上试合,在扫描电镜下测量铸件的边缘浮出量。结果第1组铸造冠与其余2组的边缘浮出量差异有显著性(P<0.05)。其余2组间的边缘浮出量差异无显著性(P>0.05)。结论Dentaurum包埋材料与Dentaurum NiCrMo合金有良好的匹配性,与其余2种合金匹配其边缘浮出量也在临床允许范围内。

Comparison of marginal adaptation of metal crown with different dental casting alloys

Objective To evaluate the influences of 3 kinds of dental casting alloys matching with Dentaurum Investment material on the marginal adaptation of the metal crown. Methods Standard as-cast specimens and round capsules which simulated post tooth crowns were made. 3 groups of wax patterns were prepared on the as-cast specimens. There were 10 wax patterns in every group. The investment material for the 3 groups was Dentaurum phosphate investment material made in German. The Dentaurum NiCrMo dental casting alloy was used in the the first group. The Shanghai NiCrMo dental casting alloy was used in the second group. The Japanese NiCrMo dental casting alloy was used in the third group.The marginal opening of the 3 groups' metal crowns were measured under SEM. Results It showed no significant differences between the second group and the third group.(P>0.05) However, there were significant differences between the first group and the other two groups.(P<0.05) Conclusion The Dentaurum NiCrMo dental casting alloy makes good match with the Dentaurum Investment material. It is necessary to adjust the expansion of the Dentaurum Investment material if it matches with the other dental casting alloys.