Comparative Evaluation of the Dimensional Accuracy of Closed Tray and Open Tray Impression Technique for Dental Implants using Two Different Impression Materials

Abstract

Introduction: In the era of fixed prosthodontics where implant restorations are being routinely used, it is imperative for the dentist to correctly record the position and orientation of the implant. This necessitates the application of correct impression procedure, impression material and accurate die materials. Aim: This study aims at evaluating and comparing the effect of closed tray and open tray impression technique with polyvinyl siloxane and polyether as impression materials on the dimensional accuracy of implant definitive casts. Materials and Methods: This in vitro study is about implant definitive casts made using the open tray and closed tray impression technique using two different impression materials i.e., polyvinyl siloxane and polyether. The Co-ordinate measuring machine was used to evaluate the dimensional accuracy of the casts, then tested at the Tata Autocomponents-Interiors and Plastic Division (IPD), Pune. A total of 60 implant definitive casts were made. A total of 30 casts were made using each impression technique. These casts were further subgrouped wherein, 15 casts were made using polyvinyl siloxane as the impression material and 15 casts were made using polyether. The unpaired t-test was used for comparison. Results: Both the open tray and closed tray impression technique are comparable to each other and there is no statistically significant difference between the two. Also, the impression materials are equally good for impression making of implants (p>0.05). Conclusion: Either of the impression techniques and material used in the study can be used to make implant definitive casts.

Keywords

• direct impression technique
• indirect impression technique
• pick-up impression technique
• polyvinyl siloxane
• polyether