Journal of AdvancedMedical and Dental Sciences Research

Background: The prime goal of any prosthodontic treatment is to provide the patient with precisely fitting restorations or prosthesis. Various impression materials have been advocated for making the impressions in fabricating fixed partial dental prosthesis. Polyvinyl siloxane impression materials also known as addition silicones have been popularized recently. Based on literature review, the accuracy and dimensional stability of elastomeric impression materials have been the subjected to numerous investigations. Aim of the study: To compare additional silicone and condensational silicone for the precision for duplicating master dies. Materials and methods: The present study was conducted in the Department of Prosthodontics of the dental institution. For the study, an acrylic model of lower 1st molar tooth was prepared based on conventional shoulder type marginal preparation, supragingivally. Two step impression techniques were administered for both techniques. Two master dies were made by these impression materials. The prepared metal casts were polished and examined for any obvious positive defects to be removed by a small round carbide bur. Results: We observed significant discrepancies in mesial and buccal margins of the prepared models. We observed that overall discrepancy was more in model fabricated from condensation silicone as compared to additional silicone. On comparing we observed statistically significant difference in case of condensation silicone. Conclusion: Within the limitation of the current study we conclude that additional silicone is a better impression material as compared to condensational silicone. Keywords: Polyvinylsiloxane, impression, restorations, prosthesis