To Evaluate the Variation in Shade by A Spectrophotometer of Porcelain Fused to Metal Samples With Respect to Repeated Firing and Variation In Lot of Ceramic - An In-vitro Study


  • College of Dentistry, Indore, Department of Prosthodontics, MP, India
  • Modern Dental College and Research Centre, Department of Prosthodontics, Indore, MP, India


Shade matching is an integral part of esthetic dentistry. Thus, this study was done to compare the variation in shade of standardized porcelain fused to metal samples after 5th, 7th and 9th firing with no repeated firing (control group) using a spectrophotometer. It also compared the variation in shade by changing the lot of ceramic of same dentinal shade. For the study 120 samples were made in the form of discs and subdivided into four groups for the required grouping. All the samples were gauged by Vernier caliper. Layering was done of the samples for wash opaque, shade opaque and lastly ceramic layer of dentine. 1st firing was wash opaque firing, 2nd firing e shade opaque, 3rd firing - 1st dentine build up, 4th firing - 2nd dentine build up and 5th firing - autoglaze. Any firing after this was considered as repeated firing. The results were calculated by using ANOVA test and ‘F test.’ Thus, within the limitations of this study it was concluded that repeated firing did not significantly affect the shade of porcelain fused to metal samples and secondly variation in batch showed a statistical significant change but within the acceptable limits of an individual’s color perception.


Shade Matching, Esthetics, Lot Of Ceramic, Spectrophotometer, Repeated Firing

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