Comparative Evaluation of Dimensional Accuracy of Autoclavable Polyvinyl Siloxane Impression Material Using Different Methods of Sterilization: An in-Vitro Study

Impression making is one of the most common procedures that are performed by dentists in day-to-day practice. These impressions can act as vehicles of transmission and carry various types of microorganisms, and with the advent of pandemic like COVID 19 and its striking variants in future, an attempt was made to compare and evaluate the dimensional accuracy of recently introduced autoclavable polyvinyl siloxane impression material upon chemical disinfection and steam autoclaving. Materials and methods: A comparative in- vitro study was conducted in which three groups were made for testing dimensional accuracy. The sample size for the study was kept 45 (15 samples in each group), test samples were made by making impression using two-step double-mix technique on the prepared three-unit bridge on the typhodont model. Statistical analysis was done using one way analysis of variance (ANOVA), independent t-test, the Shapiro–Wilk test was used to investigate the distribution of the data and Levene’s test to explore the homogeneity of the variables. Results: The mean linear distance between the two margins was as follows: Bucally: 1.7064 (Group I), 1.6850 (Group II) and 1.7039 (Group III), with mrv of 1.71 (master cast). Mesio-distally: 0.6224 (Group I), 0.6197 (Group II) and 0.6182 (Group III), mrv of 0.621(master cast). Lingually: 1.4661 (Group I), 1.4677 (Group II) and 1.4582 (Group III), with mrv of 1.470 (master cast). The difference between the calculated value and master model value was statistically significant in each group. Conclusion Within the limitations of this study, the use of this impression material may have future scope in the area of eliminating the cross infection in dental clinics and to have improved in the accuracy of the prosthesis. To improve the scope further in-vivo and in-vitro studies are required to evaluate the physical properties of this material as adequate so that it can be widely accepted in clinical practice.