Pinto Avd, Bridi E C, Amaral Flb, França Fmg, Turssi C P, Pérez C A, Martinez E F, Flório F M, Basting R T
Oper Dent. 2017 May/Jun;42(3):308-318. doi: 10.2341/16-032-L.
The purpose of this study was to evaluate the calcium (Ca) and phosphorous (P) content in enamel bleached with high and low concentrations of hydrogen peroxide (HP) using Total Reflection X-Ray Fluorescence (TXRF) and colorimetric spectrophotometry (SPEC). Forty-eight sound human third molars were used. Their roots were embedded in polystyrene resin and immersed for seven days in an artificial saliva solution. Then they were distributed into six groups to receive the bleaching treatments. The agents of high HP concentration (for in-office use) evaluated were Whiteness HP Maxx/FGM (35% HP), Whiteness HP Blue/FGM (35% HP, 2% calcium gluconate), Pola Office+/SDI (37.5% HP, 5% potassium nitrate), and Opalescence Boost/Ultradent (38% HP, 1.1% ion fluoride, 3% potassium nitrate); these agents were applied to enamel in three sessions. The agents of low HP concentration (for home use) evaluated were Pola Day/SDI (9.5% HP) and White Class 10%/FGM (10% HP, potassium nitrate, calcium, fluoride), and these agents were applied for 14 days. Enamel microbiopsies were evaluated by TXRF and SPEC analysis before the bleaching treatment (baseline), during the treatment, and 14 days after the end of the treatment. For TXRF, the Kruskal-Wallis test showed that Ca and P were not influenced by agent (p>0.05). For SPEC, Pola Office+, Opalescence Boost, Pola Day, and White Class 10% caused a decrease of Ca over time; there was a significant decrease of P over time to Pola Office+ and White Class 10%. The Spearman test showed no correlation between the Ca (p=0.987; r=-0.020) and P (p=0.728, r=0.038) obtained by SPEC and TXRF. For TXRF and SPEC, changes in Ca and P during bleaching occurred independently of the HP concentration used.
本研究的目的是使用全反射X射线荧光光谱法（TXRF）和比色分光光度法（SPEC）评估高浓度和低浓度过氧化氢（HP）漂白后的牙釉质中的钙（Ca）和磷（P）含量。使用了48颗健康的人类第三磨牙。将其牙根嵌入聚苯乙烯树脂中，并在人工唾液溶液中浸泡7天。然后将它们分为六组接受漂白处理。评估的高HP浓度（用于诊所）的试剂有Whiteness HP Maxx/FGM（35% HP）、Whiteness HP Blue/FGM（35% HP，2%葡萄糖酸钙）、Pola Office+/SDI（37.5% HP，5%硝酸钾）和Opalescence Boost/Ultradent（38% HP，1.1%离子氟化物，3%硝酸钾）；这些试剂分三个阶段应用于牙釉质。评估的低HP浓度（用于家庭）的试剂有Pola Day/SDI（9.5% HP）和White Class 10%/FGM（10% HP，硝酸钾，钙，氟化物），这些试剂应用14天。在漂白处理前（基线）、处理期间和处理结束后14天，通过TXRF和SPEC分析评估牙釉质活检样本。对于TXRF，Kruskal-Wallis检验表明Ca和P不受试剂影响（p>0.05）。对于SPEC，Pola Office+、Opalescence Boost、Pola Day和White Class 10%会导致Ca随时间减少；随着时间推移，Pola Office+和White Class 10%的P显著减少。Spearman检验表明，通过SPEC和TXRF获得的Ca（p=0.987；r=-0.020）和P（p=0.728，r=0.038）之间无相关性。对于TXRF和SPEC，漂白过程中Ca和P的变化与所用HP浓度无关。
