An in vitro study to evaluate the accuracy of dies obtained from dual-arch impression trays using addition silicone impression material and tray combinations

Abstract

Objectives: This study aims to evaluate and compare the accuracy of dies obtained from dual-arch impression trays using vinyl polysiloxane impression material and tray combinations. Materials and Methods: Typodont teeth were embedded in the maxillary and mandibular Dentoform model bases and mounted in an articulator using maximum intercuspation. Impressions were made with vinyl polysiloxane materials (Reprosil Putty, Aquasil Ultra Heavy, Aquasil Ultra LV [Dentsply International]) using one-step simultaneous dual viscosity technique in dual-arch plastic trays and metal trays as well as in full arch acrylic resin custom trays. These were compared for the dimensional accuracy with the dies prepared from typodont tooth as a control. Results obtained were statistically analyzed. Results: The results indicated that dies obtained from all the impression combinations showed increased dimension (acrylic resin custom trays 9.4 ± 0.048 mm, dual-arch plastic trays 9.5 ± 0.035 mm, and dual-arch metal trays 9.41 ± 0.017 mm) as compared to the dimension of control (9.39 ± 0.007 mm). Conclusion: All the tray impression material combinations showed variable accuracies. Full arch acrylic resin trays exhibited the greatest accuracy whereas dual-arch plastic trays showed the least accuracy. CLINICAL RELEVANCE TO INTERDISCIPLINARY DENTISTRY In fixed prosthodontics, a lower incidence of errors can be obtained using a combination of PVS impression material with metal or custom tray, thereby improving the accuracy of the subsequent restoration. Interdisciplinary dentistry necessitates good prosthodontics and as such prosthodontics is an integral part of good interdisciplinary dentistry.