Effect of Fluoride Toothpaste Containing Nano-sized Trimetaphosphate on Enamel Erosive

Objectives: The aim of this study was to investigate the effectiveness of nano-sized sodium trimetaphosphate (TMPnano) added to a fluoride (F) toothpaste on enamel erosive wear in the presence or not of the acquired pellicle.
Methods: Bovine enamel blocks (4 mm x 4 mm, n = 120) were randomly assigned into the following experimental toothpastes: Placebo (no F or TMP); 1100 ppm F (1100); 1100 ppm F containing 3% micrometric TMP (1100 TMP); 1100 ppm F containing 3% nano-sized TMP (1100 TMPnano) and 5000 ppm F (5000). The groups of blocks were further divided into two conditions: erosion in the presence of human saliva (ERO-HS, n = 60) and artificial saliva (ERO-AS, n = 60). The erosive challenge was be produced by immersion in citric acid 4x/day. The hardness surface (SHf) and cross-sectional hardness (∆KHN) were analyzed as response variables as well as surface wear. The data were submitted to two-way ANOVA followed by the Student-Newman-Keuls test (p < 0.001).
Results: SHf and ∆KHN values were significantly higher in groups treated with TMP-supplemented and 5000 toothpastes, when compared to Placebo and 1100 (p < 0.001); 1100 TMPnano and 5000 toothpastes had a greater protective effect when compared with the positive control (1100) in the presence or not of the acquired pellicle (p < 0.001).
Conclusions: With toothpaste with 1100 ppm F on enamel erosive wear was significantly improved by addition of TMPnano, reaching levels similar to those obtained after the use of 5000, regardless the presence of acquired pellicle.