Abstract
Alginate impressions were immersed in solutions of five brands of commercially available glutaraldehyde for 10 and 30 minutes, then poured with a gypsum mix.Surface roughness, scratch resistance and waviness of the stone casts obtained from the treated impressions were measured.The effect of the glutaraldehyde depended on the immersion time.In general, immersion for 30 minutes caused deterioration in the stone cast surface.There was no adverse effect when the impression was immersed in an acidic glutaraldehyde solution without the addition of alkaline buffer.These results indicate that the buffering components(mainly phosphate)remain on the alginate impresson surface after long term immersion in the glutaraldehyde solution and this inhibits the hydration of gypsum.
