Accuracy and bond strength of reversible with irreversible hydrocolloid impression systems: a comparative study.

Combinations of three reversible hydrocolloids with five irreversible hydrocolloids were evaluated for dimensional accuracy and bond strength. A stainless steel model representing two teeth prepared for a fixed partial denture was designed for an accuracy study. The recordings were made with a measuring microscope, and the tensile bond strength was determined with an Instron Universal Testing instrument. The accuracy of these materials was clinically acceptable, and the resulting models were suitable. The materials distributed by a common supplier exhibited better tensile strength, although one irreversible hydrocolloid, Jeltrate, performed well in the noncompanion combination groups. This reversible with irreversible hydrocolloid combination impression has an advantage compared with the traditional reversible hydrocolloid impression, because it does not require elaborate, expensive conditioning equipment and water cooled trays.