São Paulo State University (Unesp), School of Dentistry, Department of Pediatric Dentistry and Public Health, Rua José Bonifácio 1193, Araçatuba, SP, Cep 16015-050, Brazil.
São Paulo State University (Unesp), School of Dentistry, Department of Pediatric Dentistry and Public Health, Rua José Bonifácio 1193, Araçatuba, SP, Cep 16015-050, Brazil.
Arch Oral Biol. 2018 Jun;90:40-44. doi: 10.1016/j.archoralbio.2018.03.001. Epub 2018 Mar 3.
To evaluate in vitro the effect of neutral pH topical gels with reduced fluoride concentration (F), supplemented or not with sodium hexametaphosphate (HMP) on the remineralization of dental enamel, using a pH-cycling model. Materials and methods Bovine enamel blocks with caries-like lesions were randomly treated with five gels (n = 24/group): without F/HMP (Placebo); 4500 ppm F (4500F), 4500F plus 9% HMP (4500F + HMP); 9000 ppm F (9000F); and 12,300 ppm F (Acid gel). After pH-cycling, the percentage of surface hardness recovery (%SHR), integrated loss of subsurface hardness (ΔKHN), and concentrations of loosely- (CaF) and firmly-bound (FA) fluoride formed and retained in/on enamel were determined. The results were analyzed by ANOVA followed by the Student-Newman-Keuls test (p < 0.001).
The 4500F + HMP gel promoted the highest %SHR among all groups; the lowest ΔKHN was achieved by 4500F + HMP and Acid gel, without significant differences between these. The Acid gel group presented the highest CaF and FA formed and retained on/in enamel (p < 0.001).
Based on the present results, the addition of 9% sodium hexametaphosphate to a gel with reduced fluoride concentration (4500F) was able to significantly enhance the remineralization of artificial carious lesions in vitro when compared to 4500F, reaching protective levels similar to an acidic formulation with ∼3-fold higher fluoride concentration.
使用 pH 循环模型评估低氟浓度（F）的中性 pH 局部凝胶（添加或不添加六偏磷酸钠（HMP））对牙釉质再矿化的体外影响。
将具有龋样病变的牛牙釉质块随机用 5 种凝胶处理（每组 n=24）：无 F/HMP（安慰剂）；4500ppm F（4500F）、4500F 加 9%HMP（4500F+HMP）；9000ppm F（9000F）；和 12300ppm F（酸性凝胶）。pH 循环后，测定表面硬度恢复率（%SHR）、亚表面硬度综合损失（ΔKHN）以及松散结合（CaF）和牢固结合（FA）氟化物在牙釉质中形成和保留的浓度。结果采用方差分析（ANOVA），然后进行 Student-Newman-Keuls 检验（p<0.001）。
4500F+HMP 凝胶促进了所有组中最高的%SHR；4500F+HMP 和酸性凝胶的 ΔKHN 最低，两组间无显著差异。酸性凝胶组在牙釉质中形成和保留的 CaF 和 FA 最高（p<0.001）。
根据目前的结果，与 4500F 相比，在低氟浓度（4500F）凝胶中添加 9%的六偏磷酸钠能够显著增强人工龋损的体外再矿化，达到与浓度约高 3 倍的酸性制剂相似的保护水平。
