Reactivation of inactivated endogenous proteolytic activities in phosphoric acid-etched dentine by etch-and-rinse adhesives
Reactivation of inactivated endogenous proteolytic activities in phosphoric acid-etched dentine by etch-and-rinse adhesives
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DOI：
10.1016/j.biomaterials.2006.01.040
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发表时间：
2006-09-01
期刊：
影响因子：
14
通讯作者：
Tay, Franklin R.
中科院分区：
文献类型：
--
作者：
Mazzoni, Annalisa;Pashley, David H.;Tay, Franklin R.
通过宿主来源的基质金属蛋白酶的缓慢作用，胶原基质的自动降解发生在树脂渗透的牙本质中。由于磷酸蚀刻会使这些内源酶失活，因此令人费解的是，通过简化的蚀刻和冲洗粘合剂创建的混合层如何在体内降解。这项研究测试了零假设，即矿化牙本质、酸蚀牙本质以及酸蚀和冲洗粘合剂处理的酸蚀牙本质的相对蛋白水解活性没有差异。用拔除的人类牙齿制备的粉末状牙本质经过 17% EDTA、10% 磷酸处理，或者使用五种简化的蚀刻和冲洗粘合剂应用于 10% 磷酸蚀刻的牙本质。使用荧光素标记的明胶测定牙本质粉末的明胶分解活性。对风干、处理过的牙本质粉末进行 TEM 检查，以确认酸蚀后残留矿化牙本质的存在。 17% EDTA 显着降低了未经处理的矿化牙本质粉末（对照）的相对蛋白水解活性（73.2%），而 10% 磷酸酸蚀牙本质的降低程度最高（98.1%）。用五种简化的蚀刻和冲洗粘合剂中的任何一种处理酸蚀牙本质粉末都会导致蛋白水解活性重新激活，荧光的增加与粘合剂相应的 pH 值之间存在显着的负线性相关性 (P < 0.05)。结论是，简化的蚀刻和冲洗粘合剂可以重新激活牙本质中先前因磷酸蚀刻而失活的内源酶活性。重新激活的酶的量甚至可能超过未经处理的矿化牙本质中存在的原始量。这为酸蚀牙本质基质被这些粘合剂渗透后混合层的降解提供了解释。 (c) 2006 Elsevier Ltd. 保留所有权利。
Auto-degradation of collagen matrices occurs in resin-infiltrated dentine by the slow action of host-derived matrix metalloproteinases. As phosphoric acid-etching inactivates these endogenous enzymes, it is puzzling how hybrid layers created by simplified etch-and-rinse adhesives can degrade in vivo. This study tested the null hypothesis that there are no differences in the relative proteolytic activities of mineralised dentine, acid-etched dentine, and etch-and-rinse adhesivetreated acid-etched dentine. Powdered dentine prepared from extracted human teeth was treated with 17% EDTA, 10% phosphoric acid, or with five simplified etch-and-rinse adhesives that were applied to 10% phosphoric acid-etched dentine. The gelatinolytic activity of the dentine powder was assayed using fluorescein-labelled gelatine. TEM examination of the air-dried, treated dentine powder was performed to confirm the presence of remnant mineralised dentine after acid-etching. 17% EDTA significantly reduced the relative proteolytic activity (73.2%) of the untreated mineralised dentine powder (control), while 10% phosphoric acid-etched dentine exhibited the highest reduction (98.1%). Treating the acid-etched dentine powder with any of the five simplified etch-and-rinse adhesives resulted in the reactivation of the proteolytic activity, with a significant negative linear correlation (P < 0.05) between the increases in fluorescence and the corresponding pH values of the adhesives. It is concluded that simplified etch-and-rinse adhesives can reactivate endogenous enzymatic activities in dentine that are previously inactivated by phosphoric acid-etching. The amount of enzyme reactivated may even exceed the original quantity present in untreated mineralised dentine. This provides an explanation for the degradation of hybrid layers after acid-etched dentine matrices are infiltrated with these adhesives. (c) 2006 Elsevier Ltd. All rights reserved.