Bond strength and accuracy of combined reversible-irreversible hydrocolloid impression systems.

This study investigated the bond strength and accuracy of irreversible and reversible hydrocolloids that were modified by the manufacturer to bond to each other for use in the combination impression technique. One conventional type irreversible hydrocolloid was used because of previously reported favorable results obtained in several investigations. Tensile strength of each individual material was tested as well as the adhesive bond between reversible and irreversible hydrocolloids. Tensile bond strength was then measured for each combination of materials. Subsequently, all the materials were tested individually and in combination for dimensional accuracy.