Objectives

The objective of this study was to determine the effects of antimicrobial photodynamic therapy (aPDT) with indocyanine green (ICG) and toluidine blue (TB) on protease activity (matrix-bound cathepsin K and matrix metalloproteinase (MMP) and dentin bond strength.

Methods

Caries-free human third molars were assigned to five groups: 1—control group, 2—application of ICG with activation using an 810 nm diode (aPDT), 3—application of ICG, 4—application of TB with activation using a 660 nm diode (aPDT), and 5—application of TB. For the enzymatic investigation, dentin beams were incubated for either 3 days or 3 weeks. Aliquots of the incubation media were analyzed by ELISA for CTX (C-terminal cross-linked telopeptide of type I Collagen) and ICTP (cross-linked carboxy-terminal telopeptide of type I collagen). For microtensile bond strength testing (μTBS), composite resins were layered onto the tooth surface; the samples were then subjected to μTBS. Kruskall–Wallis and Mann–Whitney U tests were applied for statistical analysis of CTX and ICTP, one way-ANOVA and Tukey’s test were applied for statistical analysis of μTBS.

Results

Pretreating the dentin matrices with aPDT decreased the endogenous protease activity. ICG with laser activation resulted in the highest μTBS. Therefore, aPDT should be considered as a treatment method because it can reduce MMP-mediated dentin degradation and increase the μTBS.

Significance

Inhibiting endogenous protease activity improves the stability of the dentin–adhesive bond and the durability of the bond strength.

中文翻译：

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通过光动力疗法抑制组织蛋白酶 K 和基质金属蛋白酶

目标

本研究的目的是确定使用吲哚菁绿 (ICG) 和甲苯胺蓝 (TB) 的抗菌光动力疗法 (aPDT) 对蛋白酶活性（基质结合组织蛋白酶 K 和基质金属蛋白酶 (MMP) 以及牙本质结合强度）的影响。

方法

无龋人第三磨牙分为五组：1-对照组，2-使用 810 nm 二极管 (aPDT) 激活的 ICG 应用，3-ICG 的应用，4-使用 660 nm 激活的 TB 应用二极管 (aPDT)，和 5—TB 的应用。对于酶促研究，将牙本质束孵育 3 天或 3 周。孵育培养基的等分试样通过ELISA分析CTX（I型胶原的C端交联端肽）和ICTP（I型胶原的交联羧基端端肽）。对于微拉伸粘合强度测试 (μTBS)，将复合树脂分层到牙齿表面；然后对样品进行 μTBS。Kruskall-Wallis 和 Mann-Whitney U 检验用于CTX和ICTP的统计分析，单向方差分析和Tukey's检验用于μTBS的统计分析。

结果

用 aPDT 预处理牙本质基质会降低内源性蛋白酶活性。带有激光激活的 ICG 产生最高的 μTBS。因此，aPDT 应被视为一种治疗方法，因为它可以减少 MMP 介导的牙本质降解并增加 μTBS。

意义

抑制内源性蛋白酶活性可提高牙本质-粘合剂粘合的稳定性和粘合强度的耐久性。