Biofilm modification by various dental products containing calcium and phosphate

Objectives: The aim of this study was to compare the water soluble calcium phosphate level of various dental products including newly provided trial material. Calcium phosphate release from biofilm treated by each product was also explored.

Methods: Five paste products, Tooth Mousse Plus (TMP, GC), Mineral-Enriched TMP (ME-TMP, trial product), ReminPro (RP, VOCO), Clinpro Toothcream (CP, 3M ESPE) and Sensodyne Nupro Professional Toothpaste (SN, DENTSPLY) were analyzed in this study. The slurry (10wt% in water) was prepared and centrifuged at 12,000g for 15min. Levels of ions in supernatant were determined as water soluble calcium and phosphate. To assess calcium phosphate providing efficacy toward biofilm, Streptococcus mutans biofilm grown on circular sintered hydroxyapatite disk was treated by the slurry (5wt% in water) for 30min. Then, specimens were washed three times followed by incubation in Hepes buffer (pH7.0). After 1, 2, 4 and 8 hours incubation, the amount of calcium and phosphate ion released from S.mutans biofilm into the buffer were quantified. Concentration of calcium and phosphate were measured by atomic absorption spectrometer and molybdenum acid colorimetric method respectively. All data were statistically analyzed (N=6, ANOVA, Tukey's multiple comparison).

Results: The results presented below are levels (µmol/g) of water soluble calcium phosphate in each product.

a, b: Significantly different from all other values in row (P<0.01)

Amount of released ions from biofilm treated by TMP or ME-TMP were significantly higher than other group.

Conclusion: This study confirmed that only CPP-ACP based product (TMP and ME-TMP) exhibited high levels of water soluble calcium phosphate. ME-TMP has approximately 25% more water soluble calcium phosphate as compared to TMP. The biofilm treated by TMP and ME-TMP acted as good calcium phosphate reservoir.