Lepe X, Johnson G H
Department of Restorative Dentistry, University of Washington, Seattle, USA.
J Prosthet Dent. 1997 Sep;78(3):245-9. doi: 10.1016/s0022-3913(97)70021-0.
Some studies have demonstrated that short-term immersion disinfection does not affect the accuracy of polyether or addition silicone materials. Impressions are often disinfected for longer than recommended time periods.
This study evaluated these materials after simulating overnight disinfection.
Impressions were made of a master model with Extrude Extra material with Extrude Wash addition silicone and Impregum F material in combination with Permadyne Garant polyether material. Nondisinfected impressions served as controls, whereas the disinfected samples were immersed for 18 hours in a full strength 2% acid glutaraldehyde solution. Anteroposterior and cross arch dimensions of the working cast and occlusogingival, mesiodistal, and buccolingual dimensions of working die were assessed. The data were analyzed with one-way analysis of variance at "alpha" = 0.05.
No significant differences were observed for anteroposterior and cross arch dimension when compared with the master model. However, significant differences were found for occlusogingival dimension at 18 hours of disinfection for both materials. The addition silicone 18-hour disinfection group was significantly less accurate in the mesiodistal dimension.
Accuracy of both impression materials was adversely affected with 18 hours of immersion disinfection. Long-term (18 hours) immersion disinfection will affect the fit of fixed partial prostheses.
一些研究表明，短期浸泡消毒不会影响聚醚或加成型硅橡胶材料的精度。印模的消毒时间通常比推荐时间长。
本研究在模拟过夜消毒后对这些材料进行了评估。
用Extrude Extra材料、添加Extrude Wash的加成型硅橡胶以及Impregum F材料与Permadyne Garant聚醚材料组合，从主模型制取印模。未消毒的印模作为对照，而消毒后的样本在2%的浓酸性戊二醛溶液中浸泡18小时。评估工作模型的前后和跨弓尺寸以及工作模型的咬合龈向、近远中向和颊舌向尺寸。数据采用“α” = 0.05的单向方差分析进行分析。
与主模型相比，前后和跨弓尺寸未观察到显著差异。然而，两种材料在消毒18小时时，咬合龈向尺寸均发现有显著差异。加成型硅橡胶18小时消毒组在近远中向尺寸上的精度明显较低。
两种印模材料在浸泡消毒18小时后精度均受到不利影响。长期（18小时）浸泡消毒会影响固定局部义齿的贴合度。
