Comparison of Dimensional Accuracy Using Two Elastomeric Impression Materials in Fixed Prosthodontics

This study compared the dimensional accuracy of monophasic and putty-wash polyvinyl siloxanes on the inter preparation distance in fixed prosthodontics. It was carried out at the Department of Prosthodontics and Maxillofacial Prosthetics at Dashmesh Institute, Faridkot, India. A brass die simulating three unit fixed partial denture was fabricated. Two different commercially available products were used. Impressions for Putty wash (using stock tray) and Monophase (using custom tray) were made and poured with Type IV Die stone. A total of 60 impressions were made. A set of 20 impressions were poured after one hour, another set of 20 impressions were poured after 24 hours and the last set of 20 impressions were poured after 7 days. Inter-preparation distances were measured on the stone dies and compared with the master model. Results indicated that most of the inter-abutment dimension values deviated from the master model within range of (-0.11% +0.16%) percentage deviation. Under the conditions of this study, the Putty-wash and Monophase impression techniques were equally dimensionally accurate and the time of the pour did not affect the accuracy.