Assessment of Anti-caries and Stain Removal Properties of Fluoride Toothpaste

Objectives: The aim of this study was to assess the anti-cariogenic potential and stain removal ability of various fluoride pastes and novel brush-on paste containing Recaldent (CPP-ACP) and fluoride, MI One Step (MIOS，GC).
Methods: The four materials examined in this study were MIOS, Clinpro 5000 (C5000, 3M ESPE), Colgate Total Clean Mint (CTCM, Colgate) and Crest Cavity Protection (CCP, P&G). Slurry (10 wt %) was prepared and centrifuged at 12,000g for 15min. The supernatant (water soluble) was collected for analysis. Levels of calcium and inorganic-phosphate ion were determined by MXB-method and molybdenum acid colorimetric method respectively. Levels of fluoride ion were measured by ion meter (pH / ION METER F-23, HORIBA). Specimens (n=4) for stain removal were made by polishing enamel (with SIC paper) then lightly etching (0.2N HCl) and followed with stain. To stain, samples were immersed in staining broth (0.34% instant coffee, 0.34% instant tea, and 25% gastric mucin) dissolved in sterilized trypticase soy broth (Becton, Belgium) for 4 days at 37 degree. Lab value was measured by spectrophotometry (CM-3610d; MINOLTA, Japan) then stained surface was brushed using 800 strokes at 150g. After brushing Lab values were measured again. ΔE value was calculated as an index of stain removal. ΔE= [√ (ΔL²+Δa²+Δb²)]. Data were statistically analyzed with ANOVA and Turkey test (p=0.05).
Results: Mean values of bioavailable ion level of MIOS was significant higher than all other materials. C5000 containing α-TCP, CTCM and CCP had little to no bioavailable ions detected.
ΔE of MIOS and CCP were significant higher than C5000 and CTCM.
Conclusions: MIOS has high level of bioavailable ions. In addition, MIOS removed stain at similar level as CCP. MIOS may be considered as a viable clinical material for brushing demineralized teeth.