Evaluation of In-Vitro Efficacy of Active Ingredients in Dentifrice Used for Different Treatment Times / 치위생과학회지

ABSTRACT

The purpose of this study was to evaluate the in-vitro efficacy of the active ingredients of dentifrice following treatment time. The whitening effect was evaluated by a change in lightness value relative to the contact time of hydrogen peroxide, by using artificially stained hydroxyapatite discs. The anti-calculus effect was assessed based on the amount of calcium eluted from the human dental calculus by sodium pyrophosphate. Remineralization was evaluated by the Vickers hardness test following the application of sodium fluoride to bovine enamel. In order to view dentinal tubules occlusion, the formation of insoluble calcium salts by bovine dentin specimens was observed using scanning electron microscopy. Change in lightness value (ΔL) was 5.50±1.51 after 1 min of treatment, 5.73±0.43 after 3 min, 8.64±0.24 after 10 min, 18.93±0.76 after 30 min, and 27.35±0.54 after 60 min. The amount of calcium eluted from the human dental calculus was 4.23±0.14 ppm after 1 min of treatment, 4.51±0.04 ppm after 3 min, 12.12±0.16 ppm after 10 min, 17.85±0.81 ppm after 30 min, and 25.15±0.32 ppm after 60 min. The Vickers hardness change value (ΔVHN) was 1.96±1.44 after 1 min, 1.52±1.06 after 3 min, 9.06±0.15 after 10 min, 10.83±5.13 after 30 min, and 12.55±2.09 after 60 min. Partial dentinal tubules occlusion was observed at 10 min and complete occlusion was evident at 60 min. In summary, the use of patch type dentifrices for 10, 30, or 60 min were 1.57 to 8.26 times more effective than using the paste type dentifrices for 1 to 3 min. Based on these findings, it is reasonable to expect that the use of patch type dentifrices for 10 min would lead to remineralization, anti-calculus and dentinal tubules occlusion effects, and that use for 30 min would result in a whitening effect.