粘接剂对金属全冠固位力影响的实验研究

The effect of two cements on the retention of full crowns cemented on teeth abutments

目的 :观察常用的两种粘接剂对金属全冠粘接固位力的影响。方法 :通过精密机床加工制备天然基牙 ,制作全冠蜡型 ,常规包埋后用烤瓷合金 (镍铬合金 )铸造。 10个基牙随机分为两组 ,分别用磷酸锌粘固粉、玻璃离子粘固粉粘接全冠于基牙上。通过万能实验机测量记录全冠在轴向拉力作用下的粘接固位力。结果 :用磷酸锌粘固粉、玻璃离子粘固粉粘接的全冠固位力分别为 2 64 .80± 2 2 .70N、2 92 .2 4± 3 0 .0 6N ,二者间有显著性差异。结论 :磷酸锌粘固粉在基牙上对金属全冠的粘接固位力小于玻璃离子粘固粉。

Objective:To observe the retentive strength of full metal crowns cemented on teeth abutments with zinc phosphate cement (ZPC) and glass ionomer cement (GIC). Method:Complete crown preparations of extracted premolars were finely processed through the precision machine tool. Wax patterns of full crowns were fabricated and were invested and cast in a Ni-Cr cast alloy. 10 samples of teeth abutments were divided into two groups. The crowns of two groups were cemented on abutments with ZPC, GIC respectively, according to manufacturers' instructions. The crowns were pulled from the abutment by means of a 500kg load cell at crosshead speed of 1.0mm/min on a universal testing machine, and the separation force was record. Result:The retentive forces of crowns cemented on teeth with ZPC, GIC were 264.80±22.70 N, 292.24±30.06 N. The results of t-test analysis displayed statistical difference.Conclusion:The retentive strength of full metal crowns cemented on teeth abutments with ZPC was significantly lower than that with GIC.