Comparative Evaluation of Colour Stability in Laboratory Provisional Crown and Bridge Materials Exposed to Varying Concentrations of Chlorhexidine Gluconate Mouth Rinse at Different Time Intervals: An in Vitro Study.

Rehabilitations in xed prosthodontics may require an extended period of provisionalization when additional therapy is required before completion of the treatment. Interim restorations in esthetically critical areas, should be able to maintain its esthetic appearance over the term of usage besides the initial shade match. This study evaluated the colour stability of laboratory provisional materials namely Cold/Self Cure Acrylic, Heat Cure Acrylic, CAD/CAM fabricated PMMA exposed to 0.2% and 0.12% Chlorhexidine gluconate staining solutions at different time periods using a Reectance Spectrophotometer. Baseline colour measurement of all the materials were made. Fifteen samples each of SELF CURE PMMA, HEAT CURE PMMA, CAD/CAM PMMA were immersed in 0.2% and 0.12% CHX staining solutions respectively. After every 24 hours new mouth rinse solution was prepared and the specimens were taken out from previous solution and reimmersed in the new solution. Color variation of each groups were measured at the end of 2 weeks, 4 weeks, 6weeks. The result of the present study showed that there is signicant difference in the colour of laboratory provisional materials in Chlorhexidine gluconate mouth rinse. Cold cure PMMA showed maximum colour variation from baseline colour measurement at the end of 6th week whereas Heat cure PMMA and CAD CAM PMMA showed better color stability.