Effect of staining solutions on color stability of acrylic denture base resins - A spectrophotometric evaluation

The purpose of this study was to quantitatively evaluate the effect of staining solutions by spectrophotometric method on color stability of the commercially available acrylic denture base resins polymerized by different methods of cure, materials, and immersion periods. Commercially available heat cure resin (Travelon) and self cure resin (RR repair material) were selected for the study. In case of the heat cure resin, the samples were prepared by both fast cure and slow cure polymerization techniques. The samples were immersed in staining agents: Turmeric, Yoghurt, Coffee, Tea, Cocoa and Lime for a period of one day, seven days and 30 days of daily use. At the end of each staining period, the color values were measured using a reflectance spectrophotometer and the color difference was determined amongst all the groups based on CIELab system. Statistical analysis of data on 30 days showed highest degree of color change in case of turmeric followed by yoghurt, tea, coffee, lime and cocoa. The heat cure slow samples were also most color stable followed by the heat cure fast samples. The self cure samples were found to be most susceptible to the color changes. The material, method of cure, immersion periods and staining solutions were significant factors that affected color stability of acrylic denture base resins. Public wearing prosthesis should be aware of their dietary habits, if their prosthesis needs to be worn for a long period. The study also aids the dentist in selecting resins for denture construction and denture repair procedures based upon color stability under laboratory condition.