Avaliação da alteração dimensional em modelos de gesso substituindo água destilada por duas soluções desinfetantes.

Abstract

The increased concern about cross-infection, mainly with diseases such as AIDS and hepatitis B, stimulated the development of research to improve the forms of disinfection on dental routine. However, degrading effects on dimensional stability of gypsum caused by this process, reduces the quality of the models resulting in unsatisfactory prostheses. This research aims to assess an alternative in combating cross infection, from the deployment of disinfectants agents, such as chlorhexidine digluconate and quaternary ammonium, directly in the handling of gypsum type IV. The plaster models (Durone IV) were obtained from the universal mold of a rectangular base metal matrix containing two graded cylinders for measurement of the dimensional alterations. The specimens were divided into three groups: Group A - manufacturer's recommendations; Group C - replaced 50% of distilled water for chlorhexidine 2%; Group G - the liquid used was the quaternary ammonium. The comparative test used was the Mann-Whitney test. As expected, it was found no significant difference (p ≤ 0,008) between the groups analyzed. The results showed that the replacement of distilled water by chlorhexidine 2%, as well as by quaternary ammonium, did not cause significant changes in the final dimensions of the obtained models, factor of great importance for the fabrication of prostheses and possibly cause cross-infection control.