Department of Preventive and Restorative Dentistry, Araçatuba School of Dentistry, São Paulo State University - UNESP, Araçatuba, SP, Brazil.
Department of Preventive and Restorative Dentistry, Araçatuba School of Dentistry, São Paulo State University - UNESP, Araçatuba, SP, Brazil.
J Dent. 2024 Nov;150:105330. doi: 10.1016/j.jdent.2024.105330. Epub 2024 Aug 29.
To evaluate in vitro the effects of nano-sized sodium trimetaphosphate (TMPnano) and sodium fluoride (F) added to a 17.5 % hydrogen peroxide (HO) bleaching gel on the color change, enamel mechanical and morphological properties, and HO transamelodentinal diffusion.
Bovine enamel/dentin discs (n = 180) were divided according to the bleaching gel: 17.5 % HO (17.5 % HP); 17.5 % HO + 0.1 % F (HP/F); 17.5 % HO + 1 % TMPnano (HP/TMPnano); 17.5 % HO + 0.1 % F + 1 % TMPnano (HP/F/TMPnano) and 35 % HO (35 % HP). The gels were applied for 40 min on three sessions, each session spaced 7 days apart. The total color change (ΔE*) according to the Commission Internationale de l'Eclairage (CIE) Lab* color change measured by CIEDE2000 (ΔE), whitening index (ΔWI), surface hardness (SH), surface roughness (Ra), cross-sectional hardness (ΔKHN), and transamelodentinal diffusion were assessed. Enamel surfaces were examined using Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray (EDS) analysis. The data were analyzed using ANOVA, followed by the Student-Newman-Keuls test (p < 0.05).
ΔE*, ΔE, and ΔWI values were comparable among the gels that produced a bleaching effect post-treatment (p < 0.001). The HP/F/TMPnano group exhibited lower mineral loss (SH and ΔKHN), Ra, and HO diffusion compared to the 17.5 % HP and 35 % HP groups, which had the highest values (p < 0.001). SEM/EDS analysis revealed surface changes in all bleached groups, though these changes were less pronounced with F/TMPnano.
The 17.5 % HP gel containing F/TMPnano maintains the bleaching effect while reducing enamel demineralization, roughness, HO diffusion, and enamel morphological changes.
Low-Concentration HO bleaching gel containing F/TMPnano can be used as a novel approach to enhance safety and maintain the performance of aesthetic effects.
评估纳米尺寸的三聚磷酸钠（TMPnano）和氟化钠（F）添加到 17.5%过氧化氢（HO）漂白凝胶中对颜色变化、牙釉质机械和形态特性以及 HO 跨牙本质渗透性的影响。
根据漂白凝胶将牛牙釉质/牙本质圆盘（n=180）分为以下几类：17.5%HO（17.5%HP）；17.5%HO+0.1%F（HP/F）；17.5%HO+1%TMPnano（HP/TMPnano）；17.5%HO+0.1%F+1%TMPnano（HP/F/TMPnano）和 35%HO（35%HP）。凝胶在三个疗程中应用 40 分钟，每个疗程间隔 7 天。根据国际照明委员会（CIE）Lab颜色变化的 CIEDE2000（ΔE）测量总颜色变化（ΔE）、增白指数（ΔWI）、表面硬度（SH）、表面粗糙度（Ra）、横截面硬度（ΔKHN）和跨牙本质渗透性。使用扫描电子显微镜（SEM）和能量色散 X 射线（EDS）分析检查牙釉质表面。使用方差分析（ANOVA）分析数据，然后使用学生-纽曼-凯尔斯检验（Student-Newman-Keuls test）（p<0.05）。
治疗后产生漂白效果的凝胶之间的ΔE*、ΔE 和ΔWI 值无差异（p<0.001）。与 17.5%HP 和 35%HP 组相比，HP/F/TMPnano 组的矿物质损失（SH 和ΔKHN）、Ra 和 HO 扩散较低，这两组的数值最高（p<0.001）。SEM/EDS 分析显示所有漂白组的表面均发生变化，但 F/TMPnano 组的变化较小。
含有 F/TMPnano 的 17.5%HP 凝胶在保持漂白效果的同时，减少了牙釉质脱矿、粗糙度、HO 扩散和牙釉质形态变化。
含有 F/TMPnano 的低浓度 HO 漂白凝胶可作为一种增强安全性和保持美观效果的新方法。
