Citation Information :
Selvaraj S, Raju R, Zankari V, Vijayakumar M. A Spectrophotometric Analysis of Color Changes in Metal Ceramic Restorations by Varying Porcelain Thickness and Repeated Firings: An in vitro Study. Int J Prosthodont Restor Dent 2015; 5 (2):38-43.
The objective of this study is to find out the adequate porcelain thickness required for metal ceramic restorations to match the color of the shade guide and effect of repeated firing on quality and physical characteristics of dental ceramics.
Methods
Preparation of samples done first by preparing alloy substructure. A total of 15 samples of uniform thickness 0.5 mm was prepared using Ni-Cr alloy. Fusion of porcelain to alloy substructure done. Fifteen samples, five 0.5 mm thickness samples, five 1 mm samples and five 1.5 mm porcelain thickness samples were prepared. Color evaluation done by spectrophotometer.
Statistic analysis
Statistic analysis methods employed in the present study were ANOVA-one way, Scheffe's post hoc test and paired samples ‘t’ test.
Conclusion
The thickness of porcelain significantly affects the color of a given porcelain sample. Increasing the thickness gives better results. On repeated firings two and 10 firing did not affect the color stability.
How to cite this article
Raju R, Selvaraj S, Zankari V, Vijayakumar M. A Spectrophotometric Analysis of Color Changes in Metal Ceramic Restorations by Varying Porcelain Thickness and Repeated Firings: An in vitro Study. Int J Prosthodont Restor Dent 2015;5(2):38-43
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