采用不同包埋液调拌磷酸盐包埋材对铸造冠边缘适合性影响的实验研究

目的：观察采用不同包埋液调拌磷酸盐包埋材料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60个熔模，将熔模放置在60个铸型中，铸型随机分为6组。选用3种包埋液与2种包埋材料按厂商推荐比例混合调拌后，对铸型分别进行有圈包埋，采用相同的NiCrMo合金进行铸造。铸造冠在原标准帽状试件上试骀，在扫描电镜下测量铸件的边缘浮出量。结果：6组铸造冠的边缘浮出量差异无显著性（P〉0．05）。结论：不同包埋液调拌磷酸盐包埋材料对铸造冠边缘适合性无显著影响。

The effect of different investment liquid of Phosphate-bonded investment on the marginal adaptation of metal crown

Objective： To evaluate the influences of 3 kinds of investment liquid of phosphate-bonded investment on the marginal adaptation of metal crown. Methods： Standard as-cast specimens and round capsules which simulated posterior tooth crowns were made. 60 wax patterns were prepared on the as-cast specimens. There were 10 wax patterns in every group. Three types of investment liquid were mixed with two kinds of investment materials according to manufacturer＇s recommendation before poured in the molds. The NiCrMo dental casting alloy was used in the the three groups. The marginal opening of the 6 groups＇ metal crowns were measured t~nder SEM. Results： It showed no significant differences between the marginal opening of the 6 groups＇ metal crowns （ P 〉 0. 05）. Conclusion： There are no significant influences of different kinds of investment liquid of phosphate-bonded investment on the marginal adaptation of metal crown.