Comparison of a range of addition silicone putty-wash impression materials used in the one-stage technique.

This study investigated the accuracy of one-stage polyvinylsiloxane impressions recorded in metal and plastic stock trays using regular and soft putties. Impressions were made using the one-stage technique (putty and wash simultaneously) of a full arch, copper-plated typodont with turned full crown preparations. Dies resulting from all the putty-wash impressions recorded in plastic trays had significant differential die distortion at the cervical finishing line. Although President regular putty, President soft putty, Express and Provil produced acceptable dies when used with metal trays, significant differential die distortion occurred with Extrude and Reprosil. The putty-wash/plastic tray combination is unsatisfactory. Metal trays reduce die distortion with some putty-wash systems but not with others.