孔数和孔径对可拆卸式托盘取模模型精度的影响

The effect of bore number and diameter of the removable tray on accuracy of alginate impression.

目的:研究可拆卸式托盘的固位孔孔数及孔径对托盘取模精度的影响,为临床提供取模精度较好的托盘。方法:制作金属模型,用2号成品托盘,孔数44、孔径2.6mm的可拆卸式托盘,孔数32和29、孔径分别为3.0mm、3.5mm及4.0mm的2号可拆卸式托盘各取模并灌制5个石膏模型。用体视显微镜测量模型各标志点的距离,对所得数据进行统计分析。结果:①相同孔数不同孔径的可拆卸式托盘,随着孔径的增大,制取的石膏模型也变大,各线段的长度变化有明显统计学意义(p<0.01)。②相同孔径不同孔数的可拆卸式托盘,孔数多的托盘制取的石膏模型较大,变化有统计学意义(p<0.05)。③可拆卸式托盘中精度较好组的精度优于传统托盘,差异有统计学意义(p<0.05)。结论:按照适宜的孔数和孔径制成的可拆卸式托盘,精度优于其它托盘,可作为临床新型托盘应用。

Objective：To study the effects of the bore number and diameter on accuracy of alginate impression. To provide a kind of new tray with better accuracy for clinic. Method： Made a metal model simulated a three-unite fixed partial denture. Made 5 alginate impressions by traditional No.2 tray, removable tray with bore number is 44 and bore diameter is 2.6mm, removable trays with bore numbers are 29 and 32,bore diameters are 3.0 mm,3.5 mm and 4.0 mm respectively. The dimension between landmarks was measured under microscope. Result：①The bore diameter caused obvious dimension change （P〈0.01）.With longer bore diameter, the impression became bigger. ②The bore number caused dimension change （P〈0.05）, the impression made by tray with more bore was bigger. ③the knock-tray which has better accuracy in their group is better than the traditional tray （P〈0.05）.Condusion：The removable tray with properly bore number an diameter would meliorate the accuracy of alginate impressions.