Department of Pediatric Dentistry and Public Health, São Paulo State University (Unesp), School of Dentistry, Araçatuba, Rua José Bonifácio 1193, Araçatuba, 16015-050, São Paulo, Brazil.
LIEC-Department of Chemistry, Federal University of São Carlos (UFSCar), Rodovia Washington Luís, São Carlos, 13565-905, São Paulo, Brazil.
Clin Oral Investig. 2017 Jun;21(5):1821-1827. doi: 10.1007/s00784-017-2093-3. Epub 2017 Feb 28.
This study evaluated the effect of toothpastes containing 1100 ppm F associated with nano-sized sodium hexametaphosphate (HMPnano) on enamel demineralization in vitro using a pH-cycling model.
Bovine enamel blocks (4 mm × 4 mm, n = 72) selected by initial surface hardness (SHi) were randomly allocated into six groups (n = 12), according to the test toothpastes: without fluoride or HMPnano (Placebo), 550 ppm F (550F), 1100 ppm F (1100F), 1100F plus HMPnano at concentrations of 0.25% (1100F/0.25%HMPnano), 0.5% (1100F/0.5%HMPnano), and 1.0% (1100F/1.0%HMPnano). Blocks were treated 2×/day with slurries of toothpastes and submitted to five pH cycles (demineralizing/remineralizing solutions) at 37 °C. Next, final surface hardness (SHf), integrated loss subsurface hardness (ΔKHN), integrated mineral loss (gp × cm), and enamel fluoride (F) concentrations were determined. Data were analyzed by ANOVA and Student-Newman-Keuls test (p < 0.001).
Toothpaste with 1100F/0.5%HMPnano led to the lowest mineral loss and the highest mineral concentration among all groups, which were 26% (SHf) and 21% (ΔKHN) lower and ~58% higher (gp × cm) when compared to 1100F (p < 0.001). Similar values of enamel F were observed for all fluoridated toothpastes (p > 0.001).
The addition of 0.5%HMPnano to a 1100 F toothpaste significantly enhances its effects against enamel demineralization when compared to its counterpart without HMPnano in vitro.
Toothpaste containing 1100 ppm F associated with HMPnano has a higher potential to reduce the demineralization compared to 1100 ppm F. This toothpaste could be a viable alternative to patients at high risk of caries.
本研究通过 pH 循环模型，评估含有 1100ppm F 的牙膏与纳米级六偏磷酸钠（HMPnano）联合应用对体外牙釉质脱矿的影响。
根据试验用牙膏，将初始表面硬度（SHi）选择的 4mm×4mm 的牛牙釉质块（n=72）随机分为 6 组（n=12）：无氟或 HMPnano（安慰剂）、550ppm F（550F）、1100ppm F（1100F）、浓度为 0.25%的 1100F 加 HMPnano（1100F/0.25%HMPnano）、0.5%（1100F/0.5%HMPnano）和 1.0%（1100F/1.0%HMPnano）。每天用牙膏糊剂处理 2 次，并在 37°C 下进行 5 次 pH 循环（脱矿/再矿化溶液）。随后，测定最终表面硬度（SHf）、表面下硬度损失积分（ΔKHN）、整体矿物损失（gp×cm）和牙釉质氟（F）浓度。数据采用方差分析和学生-纽曼-凯尔斯检验（p<0.001）进行分析。
与 1100F 组相比，含 1100F/0.5%HMPnano 的牙膏导致最低的矿物损失和最高的矿物浓度，其 SHf 降低 26%，ΔKHN 降低 21%，gp×cm 增加 58%（p<0.001）。所有含氟牙膏的牙釉质 F 浓度相似（p>0.001）。
与不含 HMPnano 的 1100F 牙膏相比，在 1100F 牙膏中添加 0.5%HMPnano 可显著增强其抗牙釉质脱矿作用。
与含 1100ppm F 的牙膏相比，含 HMPnano 的 1100ppm F 牙膏具有更大的减少脱矿的潜力。对于高龋齿风险的患者，这种牙膏可能是一种可行的替代选择。
