The Pellicle Cleaning Ratio of One Charcoal-based Dentifrice

Objectives: Activated charcoal toothpastes claim to effectively whiten teeth. The aim of this in vitro study was to evaluate the Pellicle Cleaning Ratio (PCR) of one dentifrice with activated charcoal
Methods:
54 bovine enamel specimens (Ø 6 mm, T 2 mm) were used for this study. To generate discoloration, the specimens were polished and thereafter stored in human saliva for 2 min, 4 min in 0.2% chlorhexidine and 4 min in black tea (3g/100ml water at 50°C) and left dry until the next cycle. After saliva and chlorhexidine exposition, the specimens were placed in distilled water for 30 sec. This cycle was repeated eight times per hour. Specimens were brushed with 800 strokes at a load of 1.5N. All treatments were performed on an automatic brushing machine using standard ADA toothbrushes and slurries. The two dentifrices were an activated charcoal dentifrice; Curaprox black (n=18) and a whitening dentifrice, Colgate Max White (n=18). The reference dentifrice (n=18) was a calcium pyrophosphate preparation according to ISO 11609 (PCR = 100). Specimens’ colours (L indicates light / dark) were evaluated by using a chromameter (ShadeEye NCC, Shofu Inc. Kyoto, Japan) before and after discoloration (initial, i), and after brushing (final, f). Specimens’ treatment effects were assessed and relative efficacy compared to the reference dentifrice was calculated as follows:
PCR = {(L*_f-L*_i) / mean of ΔL reference dentifrice _(f-i)} x 100
Data analysis was accomplished using the Kolomogorov-Sminov und ANOVA Test (p<0.05).
Results: The mean (standard deviation) PCR value was 89.56 (15.99) for Curaprox black and 89.89 (15.21) for Colgate Max white. No statistically significant differences were found between the two groups.
Conclusions: The results of this in vitro study show that the activited charcoal test dentifrice is equally effective in removing surface stains when compared to a whitening dentifrice.