IADR Abstract Archives
Effect of Sodium Acid Pyrophosphate on Toothpaste Dentin Abrasivity
Objectives: To evaluate and outline the effect of sodium acid pyrophosphate on toothpaste dentin abrasivity and further understand the chemical factors other than abrasives that affect RDA of Toothpaste
Methods: Dentin specimens underwent standard preparation, preconditioning and abrasivity testing according to the ISO 11609 requirements for radiotracer method. Four test dentifrices consisting of hydrated silica abrasive with various levels of sodium acid pyrophosphate were used.
Results: The Relative Dentin Abrasion (RDA) results are shown in the table below. As evident from the results, inclusion of sodium acid pyrophosphate (SAPP) and its interaction with dentin, statistically significantly increases the RDA values. Additionally, pH adjustments did not seem to affect the RDA values when similar level of SAPP was used in the formulation. Further, experiments were conducted with SAPP levels ranging from 0% to 8% in PBS solution at pH 7 with hydroxyapatite disks to examine the chelating power of SAPP. Excellent correlation was found and it was demonstrated that as the polyphosphate concentration was increased with levels corresponding to 0%, 2%, 4%, 6%, 8%, the calcium level was promoted with concentrations 0.51ppm, 8.9ppm, 13.5ppm, 18.9ppm, 28.8ppm respectively.
Conclusions: These results show that polyphosphates can significantly increase the abrasiveness of dentifrices when used in addition to the abrasive system. Polyphosphates are well known calcium chelating agents, and, when incorporated in formulation could cause increase in RDA values. This study may provide a better understanding of chemical factors which primarily affects the abrasivity of dentifrice composition.
Methods: Dentin specimens underwent standard preparation, preconditioning and abrasivity testing according to the ISO 11609 requirements for radiotracer method. Four test dentifrices consisting of hydrated silica abrasive with various levels of sodium acid pyrophosphate were used.
Results: The Relative Dentin Abrasion (RDA) results are shown in the table below. As evident from the results, inclusion of sodium acid pyrophosphate (SAPP) and its interaction with dentin, statistically significantly increases the RDA values. Additionally, pH adjustments did not seem to affect the RDA values when similar level of SAPP was used in the formulation. Further, experiments were conducted with SAPP levels ranging from 0% to 8% in PBS solution at pH 7 with hydroxyapatite disks to examine the chelating power of SAPP. Excellent correlation was found and it was demonstrated that as the polyphosphate concentration was increased with levels corresponding to 0%, 2%, 4%, 6%, 8%, the calcium level was promoted with concentrations 0.51ppm, 8.9ppm, 13.5ppm, 18.9ppm, 28.8ppm respectively.
Conclusions: These results show that polyphosphates can significantly increase the abrasiveness of dentifrices when used in addition to the abrasive system. Polyphosphates are well known calcium chelating agents, and, when incorporated in formulation could cause increase in RDA values. This study may provide a better understanding of chemical factors which primarily affects the abrasivity of dentifrice composition.