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

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 (${\Delta}L$) was $5.50{\pm}1.51$ after 1 min of treatment, $5.73{\pm}0.43$ after 3 min, $8.64{\pm}0.24$ after 10 min, $18.93{\pm}0.76$ after 30 min, and $27.35{\pm}0.54$ after 60 min. The amount of calcium eluted from the human dental calculus was $4.23{\pm}0.14ppm$ after 1 min of treatment, $4.51{\pm}0.04ppm$ after 3 min, $12.12{\pm}0.16ppm$ after 10 min, $17.85{\pm}0.81ppm$ after 30 min, and $25.15{\pm}0.32ppm$ after 60 min. The Vickers hardness change value (${\Delta}VHN$) was $1.96{\pm}1.44$ after 1 min, $1.52{\pm}1.06$ after 3 min, $9.06{\pm}0.15$ after 10 min, $10.83{\pm}5.13$ after 30 min, and $12.55{\pm}2.09$ 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.

치약용 약효제의 적용시간에 따른 실험실적 효능 연구

페이스트 치약의 구강 내 사용시간(1~3분)과 사용시간을 길게 조절할 수 있는 부착형 치약의 사용시간을 고려하여 치약제의 유효성분을 처리시간 조건별로(1분, 3분, 10분, 30분 및 60분) 미백 효과, 항치석 효과, 재광화 효과 및 상아세관의 폐쇄 효과를 실험실적으로 평가한 결과 다음과 같은 결과를 도출하였다. 처리 시간대별 명도 변화값(${\Delta}L$)은 1분 $5.50{\pm}1.51$에서 60분 $27.35{\pm}0.54$였고 치석으로부터 제거된 칼슘 양(ppm)은 1분 $4.23{\pm}0.14$에서 60분 $25.15{\pm}0.32$였으며 경도 증가값은 1분 $1.96{\pm}1.44$에서 60분 $12.55{\pm}2.09$였다. 상아세관의 폐쇄 정도는 10분 처리에서 일부 상아세관의 폐쇄가 관찰되기 시작하여 60분 처리에서는 대부분의 상아세관의 폐쇄가 관찰되었다. 본 실험조건에서는 처리시간을 10분에서 60분 처리시 1분에서 3분 처리할 때보다 최소 1.57배에서 최대 8.26배까지 효능을 증가시켰으며 재광화 효과, 항치석 효과 및 상아세관 폐쇄 효과에서는 사용시간 10분 이상에서 적절하였고 미백효과에서는 30분 이상이 보다 효과적일 것으로 생각되었다.