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Numerous factors are known to affect the accuracy of elastomeric impression materials. Factor often overlooked is the quality of the bond between putty and wash during corrective reline impression technique. The putty-wash bond strength must be strong enough to overcome the local stress at putty-wash interface. It is not always possible to avoid saliva contamination in making corrective wash impression. And putty preliminary impression material can be used as a template for provisional restoration. Human saliva and the residual monomer of autopolymerizing acrylic resin are thought to affect the bond strength and the failure type. @ES This study examined the effect of contaminants like human saliva, and residual resin monomer on the putty-wash bond strength and the effectiveness of treatment. @EN 1. Of the tested three brands of Vinyl Polysiloxane impession meterial, Express exhibited the greatest bond strength followed by Eamix and Perfect showed the lowest putty-wash bond strength. 2. Coating the putty substrates with human saliva did not produce decreased failure load in all the brands of Vinyl Polysiloxane impression material. 3. Of the three brands of VPS impression material that were exposed to methhylmethacrylate resin(Jet), only the putty-wash bond strength of the Perfect group diminished significantly. Moreover, all the specimens from group C of Perfect exhibited adhesive failure. 4. Exposing the substrates to ethylmethacrylate resin(SNAP) diminished the putty-wash bond strength significantly. With Perfect and Examix, failure occured cohesively through the light-body, whereas with Express, failure occured adhesive-cohesively. 5. Removing approximately 1mm thickness of the contaminated putty interface was the most effective treatment in countering the undesirable effect caused by residual resin monomer. The putty-wash bond strength of the groups that were treated with 1mm even putty reduction was not significantly different from those of control groups. With Perfect and Examix, cleaning the specimens with gauze soaked in 70% isopropyl alcohol increased the putty-wash bond strength, but was not as effective as 1mm even reduction of contaminated putty substrates. With Express, 70% isoproryl alcohol treatment exhibited comparable putty-wash bond strength to that of control group.
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