Dental Impression Materials: Reactor Response

¹ Department of Dental Biomaterials, College of Dentistry, University of Florida, Gainesville, Florida 32610

A review of the literature reveals an abundance of research papers which are focused on the physical properties and "simulated" clinical performance of impression materials. The three major developments during the past two decades were: (1) the introduction of the dimensionally stable addition silicones, (2) the development of dustless alginates, and (3) the reduction in technique sensitivity which resulted from the availability of automatic-mixing syringe tips. These syringe tips ensure consistently homogeneous mixtures of base and catalyst pastes with reduced waste. In addition, the more rapid mixing potential extends the traditional working time of the material.

Little progress has been made toward correlating in vitro properties with in vivo performance. Since typical in vitro studies of impression materials are conducted under nearly ideal conditions, the information derived is of relatively limited value in predicting their clinical performance under more demanding conditions. Future research should focus more on clinically relevant properties, including freedom from porosity, viscosity-time relationships, tissue displacement potential, tear strength, elastic recovery, sensitivity to storage conditions, compatibility with die stones, degradation potential after exposure to disinfectant and sterilizing solutions, and ability to be re-poured accurately.