Year : 2019

Volume : Volume 10

Issue : Issue 4

Address for correspondence :
Dr. Pragya Pandey.
dentistpragya20feb@gmail.com

Abstract

Background:  Various materials and techniques have been used for complete crown fabrication. Conventional method of casting & investing requires around 2-4 hours, which includes minimum 1 hour of bench set for the invested ring & 1-2 hours for preheating cycle. The whole process is time consuming. This study aims to evaluate & compare vertical marginal discrepancy of deep chamfer finish line in metal copings fabricated by conventional & accelerated preheated cycle for casting. Materials and Methods: 60 stone dies were poured from impression made with master die having deep chamfer finish line. Conventional & accelerated method of casting were performed according to manufacturer’s recommendation. Each casting & its respective stone die were examined for vertical discrepancy at 4 predetermined sites. Mean of both groups were compared with t-test. Result: Mean value of vertical marginal discrepancy for conventional group was 33.3 microns & for accelerated group was 37.8 microns. Conclusion: The vertical marginal discrepancy of Ni-Cr single PFM copings obtained by employing conventional casting technique & by accelerated casting technique was statistically insignificant.

Keywords: Accelerated casting, Casting, Marginal Discrepancy, Marginal fit, Metal copings, Phosphate bonded investment.