Color stability and fluorescence of hybrid ceramic laminates immersed in different staining solution

Abstract

This study was designed to evaluate the effect of four beverages on the color stability and fluorescence intensity of three different ceramic materials. The materials used in this study were Lava Ultimate,Vita Enmaic and Vita block markII. These materials were cut in slices with the same dimensions(13mm x 13mm x 0.5mm) using the isomet 4000 machine then they were finished using special kit and cleaned with distilled water in an ultrasonic cleaner.

All slices were measured for color and fluorescence intensity prior to immersion. Color was measured using spectrophotometer and fluorescence was measured using spectrofluorometer. Twenty slices of each material were assigned into 4 groups (5 each) according to type of staining solution. First group was immersed into 50 ml coffee, the second was immersed into 50 ml. tea, the third was immersed into Pepsi 50 ml. and last group was immersed into 50 ml. distilled water (control group). All groups were held in an incubator for 30 days. Then they were measured again after immersion for both color and fluorescence intensity.

The results revealed that there was a significant effect of coffee on all groups due to the yellow stains which have low polarity and so eluted at a later time. Pepsi has followed coffee in its stainig effect on the three materials followed by tea and then distilled water. As for the materials, Lava Ultimate samples have shown the highest change in color and fluorescence intensity due to its resin content which cause more staining solutions to be absorbed/adsorbed followed by Vita Enamic and finally Vita block markII which showed the least change in both color and fluorescence.

Limitations of this study were not assessing the influence of saliva, thermal stress, acidic pH, complex dietary colorants, fluid dynamics, time and mechanical cleanings which can potentially affect color stability . Also, the effect of cementation on color and fluorescence of restorative materials was not mentioned here. Further studies should be done to investigate the effect of these factors.