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A standardized master die was fabricated and seventy-five PVS test samples were made. The samples were examined pre and post-immersion under visual observation for surface detail reproduction, travelling microscope for measurement of dimensional stability and surface profilometer (3D) for evaluation of surface texture. Materials and Methods: The impressions were then divided into five groups (fifteen samples per group) and subjected to a ten minutes immersion with 2% glutaraldehyde (Group I), 1% sodium hypochlorite (Group II), freshly prepared electrolyzed oxidizing water (EOW) with different pH values-acidic (Group III), alkali (Group IV) and neutral (Group V).
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For reprints contact: Aim: The aim of this in vitro study was to comparatively evaluate the effect of chemical disinfectants on the surface detail reproduction, dimensional stability and surface texture of polyvinyl siloxane (PVS) impressions. This is an open access journal, and articles are distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as appropriate credit is given and the new creations are licensed under the identical terms. Comparative evaluation of the effect of electrolyzed oxidizing water on surface detail reproduction, dimensional stability and surface texture of poly vinyl siloxane impressions.
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How to cite this article: Mahalakshmi AS, Jeyapalan V, Mahadevan V, Krishnan CS, Azhagarasan NS, Ramakrishnan H. The 12-hour time of contact between alginate and the plaster cast is not recommended because it influences the quality of the plaster cast. The results showed significant difference (P ≤ 0.05) between groups in two of the three properties examined: surface detail and microhardness, which decreased as the time of contact rose. The microhardness was determined for each sample by making six indentations with a Vickers diamond pyramid indenter (Buehler, Lake Bluff, USA) under a load of 100 gF for 15 s. Surface detail and dimensional stability were tested by one calibrated examiner using a visual analysis and a profilometer (Profile Projector Nikon model 6C, Nikon Corporation, Tokyo, Japan), respectively, to evaluate the quality of reproduction of the lines and the distances between them. All the specimens were stored up to 48 hours until they underwent laboratory testing. The samples were divided into two groups: Group 1 (G1) – with time of contact of 1 hour and Group 2 (G2) – 12 hours of contact. Thirty cylindrical specimens of orthodontic gypsum Type III were made by means of impressions of a stainless steel master model which had five reference lines in the upper surface. The aim of this study was to verify the influence of the time of contact between alginate and gypsum after the modeling procedure on the properties of the plaster cast, such as surface detail, dimensional stability and microhardness. Conclusion: According to the results of this study, pouring of impression up to 9 hours can negatively affect the cast model properties in the term of details richness. In the meanwhile, hardness was improved with increasing contact time. Results: The dimension stability of cast models was not affected by increasing contact time between type III dental stone and alginate impression while surface details decreased. The samples were evaluated under light microscope for surface details, measured by digital caliper for dimension stability and hardness was tested by making indentation on the cast then measuring the depth using digital caliper. Thirty-seven cast models were separated after one hour (control group) and 30 cast models were separated from impressions after 9 hours. Material and methods: Sixty-seven cast models were obtained from stainless steel cylinder using alginate impression material and type III dental stone. Objective: To measure the effect of different contact time between the alginate impression and type III dental stone on cast model properties in the terms of dimension stability, hardness and surface details reproduction.
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