Materials and Methods: One hundred and twenty discs samples (10 mm in diameter and 2mm thickness) were prepared. Out of which sixty discs were prepared from FiltekTM Z350 restorative of A2 shade in group 1, and sixty discs were prepared from Spectrum TPH3 restorative of A2 shade in group 2. All specimens were polymerized by a LED light-curing unit according to manufacturer's recommendations. Each disc specimen from both groups was placed in 20 ml distilled water individually at 37°C for 24 hours in incubator.Initial colorimetric evaluations (baseline) of all specimens (average of 5 CIE lab readings per specimen) were measured with a SF 600 Datacolor Spectrophotometer using CIE (Commission International de l' Eclairage) L*a*b*. Each group was further divided in two subgroups equally. One subgroup of each group was immersed in staining media (Coffee) and other in distilled water. Each sample was placed individually at 37°C for 7days in incubator. On the 8th day final colorimetric reading was taken and ΔE measured.
Results: Upon visual examination all specimens exhibited discoloration. For statistical evaluation, paired t test was used at a significance level of 0.01.Upon immersion in coffee solution discolouration seen in FiltekTM Z350 (ΔE=2.78(±0.72) was significantly greater (p=0.000) than spectrum TPH3 (ΔE=1.96(±0.79). Between the solutions tested, the discolouration caused by coffee (ΔE=2.3(±0.85) was significantly (p= 0.000) greater than distilled water (ΔE=1.0(±0.51), suggesting that coffee is more stain inducing agent than distilled water.
Conclusion: This in vitro study illustrates that the stains induced by coffee was significantly higher than distilled water.