Alcan Toros, Ceylanoğlu Cenk, Baysal Bekir
Department of Orthodontics, Marmara University, Istanbul, Turkey.
Angle Orthod. 2009 Jan;79(1):30-6. doi: 10.2319/100307-475.1.
To investigate the effects of different storage periods of alginate impressions on digital model accuracy.
A total of 105 impressions were taken from a master model with three different brands of alginates and were poured into stone models in five different storage periods. In all, 21 stone models were poured and immediately were scanned, and 21 digital models were prepared. The remaining 84 impressions were poured after 1, 2, 3, and 4 days, respectively. Five linear measurements were made by three researchers on the master model, the stone models, and the digital models. Time-dependent deformation of alginate impressions at different storage periods and the accuracy of traditional stone models and digital models were evaluated separately.
Both the stone models and the digital models were highly correlated with the master model. Significant deformities in the alginate impressions were noted at different storage periods of 1 to 4 days. Alginate impressions of different brands also showed significant differences between each other on the first, third, and fourth days.
Digital orthodontic models are as reliable as traditional stone models and probably will become the standard for orthodontic clinical use. Storing alginate impressions in sealed plastic bags for up to 4 days caused statistically significant deformation of alginate impressions, but the magnitude of these deformations did not appear to be clinically relevant and had no adverse effect on digital modeling.
研究藻酸盐印模不同储存时间对数字模型精度的影响。
从一个主模型上取105个印模，使用三种不同品牌的藻酸盐材料，并在五个不同的储存时间段灌制石膏模型。总共灌制了21个石膏模型并立即进行扫描，制备了21个数字模型。其余84个印模分别在1、2、3和4天后灌制。由三名研究人员对主模型、石膏模型和数字模型进行五项线性测量。分别评估不同储存时间段藻酸盐印模的时间依赖性变形以及传统石膏模型和数字模型的精度。
石膏模型和数字模型与主模型均高度相关。在1至4天的不同储存时间段，藻酸盐印模出现明显变形。不同品牌的藻酸盐印模在第一天、第三天和第四天彼此之间也存在显著差异。
数字化正畸模型与传统石膏模型一样可靠，可能会成为正畸临床应用的标准。将藻酸盐印模密封在塑料袋中储存长达4天会导致藻酸盐印模出现统计学上显著的变形，但这些变形的程度似乎在临床上并无关联，且对数字建模没有不利影响。
