An in vitro digital comparative evaluation of the accuracy and dimensional stability of vinyl polyether silicone impression material with the conventionally used elastomeric materials scanned using a blue light scanner

Abstract

Background: The development of material science has allowed integrating qualities of polyether (PE) and Vinyl Polysiloxane (VPS) into a newer material Vinyl polyether silicone (VPES). There is limited literature available on this combination material. The aim was to evaluate and compare the accuracy and dimensional change of elastomeric impression materials with a three-dimensional (3D) approach. Materials and Methodology: Impressions were made of standard tooth model and custom trays using the three monophase impression materials, i.e., Group A–Vinyl polysiloxane (VPS), Group B-Polyether (PE), and Group C-Vinyl Polyether silicone (VPES). All the impressions were digitized and compared on eight predetermined points using a 3D compare software by the superimposition of computer-aided design files of impressions onto that of Standard tooth model. Three-dimensional comparison is repeated after storage of impressions for 1 week to re-evaluate the dimensional stability of the impression materials. Results: The average measurement of mean discrepancies of all the 8 points obtained on day 1 for VPS, PE, and VPES were 75.758 μm, 139.52 μm, and 49.24 μm, respectively, which helps in the determination of accuracy and after interval of 1 week 91.27 μm, 157.25 μm, and 89.76 μm, respectively, which helps to deduce that the linear dimensional change values for Group A, Group B, and Group C were 15.52 μm, 17.73 μm, and 40.52 μm, respectively. Conclusions: Average dimensional accuracy was highest of VPES followed by VPS and PE. Whereas VPS impression material shows the highest dimensional stability after prolonged storage of 1 week, followed by PE and then VPES impression material.