偏磷酸酸蚀时间和 pH 值对牙釉质和牙本质粘结性能的影响。

Impact of pH and application time of meta-phosphoric acid on resin-enamel and resin-dentin bonding.

机构信息

Department of Postgraduate Program in Dentistry, CEUMA University, São Luis, Maranhão, Brazil.

Department of Restorative Dentistry, School of Pharmacy, Dentistry and Nursing, Federal University of Ceará, Fortaleza, Ceará, Brazil.

出版信息

J Mech Behav Biomed Mater. 2018 Feb;78:352-361. doi: 10.1016/j.jmbbm.2017.11.028. Epub 2017 Nov 22.

DOI:10.1016/j.jmbbm.2017.11.028

PMID:29202298

Abstract

PURPOSE

To evaluate the immediate microshear resin-enamel bond strength (μSBS) and the immediate and 6-month microtensile bond strength (μTBS) and nanoleakage (NL) of the adhesive interface performed by different pHs of 40% meta-phosphoric acid (MPA) were compared with conventional 37% ortho-phosphoric acid (OPA) under different application times. Additionally, the enamel etching patterns were evaluated and the chemical/morphological changes induced by these differents groups were evaluated.

MATERIALS AND METHODS

One hundred and ninety-eight extracted human molars were randomly assigned into experimental groups according to the combination of independent variables: Acid [37% ortho-phosphoric acid (OPA), 40% meta-phosphoric acid (MPA) at pHs of: 0.5, 1 and 2] and Application Time [7, 15 and 30s]. Enamel-bond specimens were prepared and tested under μSBS. Resin-dentin beams were tested under μTBS tested immediately or after 6-months of water storage. Nanoleakage was evaluated using bonded-beams of each tooth/time-period. Enamel etching pattern and chemical and ultra-morphology analyses were also performed. The μSBS (MPa) data were subjected to a two-way repeated measures ANOVA (Acid vs. Application time). For μTBS, Acid vs application time vs storage time data were subjected to three-way ANOVA and Tukey's test (α = 0.05).

RESULTS

MPA pH 0.5 showed μTBS similar to OPA, independently of the application time on enamel (p>0.05) or dentin (p>0.05). OPA provided higher nanoleakage values than MPA (p = 0.003). Significant decreases in TBS and increases in NL were only observed for OPA after 6 months (p = 0.001). An increase in the application time resulted in a more pronounced etching pattern for MPA. Chemical analysis showed that dentin demineralized by MPA depicted peaks of brushite and octacalcium phosphate. MPA exposed less collagen than OPA. However, optimal results for MPA were dependent on pH/application time.

CONCLUSION

The use of 40% meta-phosphoric acid with a pH of 0.5 is an alternative acid-etching agent for dentin and enamel bonding. Furthermore, the use of MPA preserves the resin-dentin interface over a 6-months period, due to presence of brushite and octacalcium phosphate and a reduced demineralization pattern.

摘要

目的

评估不同 pH 值的 40% 多聚磷酸（MPA）与传统 37% 正磷酸（OPA）相比，在不同应用时间下对牙釉质的即时微观树脂-牙釉质结合强度（μSBS）和即时及 6 个月微观拉伸结合强度（μTBS）和纳米渗漏（NL）的影响。此外，还评估了牙釉质蚀刻图案，并评估了这些不同组引起的化学/形态变化。

材料和方法

将 198 颗人离体磨牙随机分为实验组，根据独立变量的组合：酸[37%正磷酸（OPA）、pH 值分别为 0.5、1 和 2 的 40%多聚磷酸（MPA）]和应用时间[7、15 和 30s]。制备牙釉质-粘结标本，在 μSBS 下进行测试。立即或在 6 个月水储存后，对树脂-牙本质梁进行 μTBS 测试。使用每颗牙/时间周期的粘结梁评估纳米渗漏。还进行了牙釉质蚀刻图案以及化学和超微结构分析。将 μSBS（MPa）数据进行双因素重复测量方差分析（酸 vs. 应用时间）。对于 μTBS，酸 vs. 应用时间 vs. 储存时间的数据进行三因素方差分析和 Tukey 检验（α=0.05）。

结果

MPA pH 值为 0.5 时，在牙釉质上（p＞0.05）或牙本质上（p＞0.05），与应用时间无关，其 μTBS 与 OPA 相似。与 MPA 相比，OPA 提供了更高的纳米渗漏值（p=0.003）。仅在 6 个月后观察到 OPA 的 TBS 显著降低和 NL 增加（p=0.001）。应用时间的增加导致 MPA 的蚀刻图案更加明显。化学分析表明，用 MPA 脱矿的牙本质显示出透钙磷石和八钙磷酸盐的峰值。MPA 暴露的胶原蛋白少于 OPA。然而，MPA 的最佳结果取决于 pH 值/应用时间。