Research Summary abstract
British Dental Journal 202, 36 - 37 (2007)
Published online: 13 January 2007 | doi:10.1038/bdj.2006.119
Subject Categories: Infection control | Prosthetic dentistry
Disinfection of impression materials and casts
R. W. Wassell, Dr1
- Allows dental practitioners to recognise that immersion disinfection may have detrimental effects on the impression materials and gypsum casts poured from them.
- Details what categories of impression materials may be subject to these problems with immersion disinfection.
- Provides a working solution to the problem.
Abstract
Objective This study investigated the effect of a commonly used immersion disinfectant upon three different impression materials and any subsequent effects on the abrasion resistance, hardness and surface detail reproduction of gypsum casts.
Design A laboratory study.
Materials and methods Under standardised conditions a total of 120 impressions were made of a ruled test block using irreversible hydrocolloid (Alginoplast), an 'alginate alternative' addition-cure silicone (Position Penta) and a conventional addition-cure silicone (President). The impressions were examined for surface detail reproduction prior to and after disinfection with Perform-ID. The type III casts were evaluated for surface detail reproduction, surface hardness and abrasion resistance.
Results (1) None of the disinfected alginate specimens could reproduce the 50 
m line. (2) Casts produced from the disinfected alginate were significantly less hard than from disinfected Position Penta and President (P <0.001). (3) Disinfection significantly affected the abrasion resistance of casts made from Position Penta (P = 0.029). (4) Disinfection did not significantly affect President or its subsequent casts (P >0.05).
Conclusion If disinfecting with Perform-ID, the impression should be made with a conventional addition-cured silicone if good surface detail reproduction of the impression material and a hard and abrasion resistant type III gypsum cast are required.
- Senior Lecturer and Honorary Consultant, Department of Restorative Dentistry, School of Dental Sciences, University of Newcastle
