三种形状藻酸盐印模尺寸精确性分析

目的:本实验旨在比较使用藻酸盐印模材料制取不同形状物体阴模过程中的尺寸精确性.方法:分别使用藻酸盐印模材料制取正方体,圆柱体、三角体阴模,并用电子数显卡尺测量灌注的普通石膏、硬石膏、超硬石膏模型试件的尺寸,并与实物尺寸进行比较分析.数据进行ANOVA(α=0.05).结果:圆柱体印模尺寸变化较大,正方体印模尺寸变化较小,而三角体印模尺寸变化居中(P＜0.05).正方体的普通石膏灌注阴模组,硬石膏灌注阴模组和超硬石膏灌注阴模组的尺寸变化百分率分别是0.044%,0.128%,0.370%.圆柱体的普通石膏灌注阴模组,硬石膏灌注阴模组和超硬石膏灌注阴模组的尺寸变化百分率分别是0.745%,0.665%,0.369%.三角体的普通石膏灌注阴模组,硬石膏灌注阴模组和超硬石膏灌注阴模组的尺寸变化百分率分别是0.557%,0.595%,0.561%.结论:三种形状中正方体对藻酸盐印模制取的尺寸变化影响较小,三角形次之,圆柱体变化较大.

Analysis of size accuracies of various shapes of alginate impression

Objective： To observe the size accuracies of alginate impression after taking various shapes of objectives.Methods： Alginate impression paste was used to take various shapes of objectives,including square,cylinder and triangle.Sizes of different gypsum models were measured using electronic caliper rule.The measured data were compared with actual size using ANOVA.Results： Cylinder impression showed the largest dimensional changes.And the size changes degree of square impression was between cylinder impression＇s and triangle impression＇s（P 〈0.05）.In the square group,dimensional change ratios were 0.044%,0.128% and 0.370%,respectively.In the cylinder group,dimensional change ratios were 0.745%,0.665% and 0.369%,respectively.In the triangle group,dimensional change ratios were 0.557%,0.595% and 0.561%,respectively.Conclusion： Various shapes of objective resulted in different size accuracies.Dimensional change： cylindertrianglesquare.