1 Department of Biomedical and Neuromotor Sciences, DIBINEM, University of Bologna-Alma Mater Studiorum, Bologna, Italy.
2 Division of Restorative Sciences, University of Southern California Herman Ostrow School of Dentistry, Los Angeles, CA, USA.
J Dent Res. 2017 Jul;96(8):902-908. doi: 10.1177/0022034517708312. Epub 2017 May 12.
The use of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide HCl (EDC) has recently been investigated for its effectiveness in the prevention of collagen degradation over time and the improvement of resin-dentin bond durability. The objective of the present study was to evaluate the effects of a 0.3 M EDC-containing conditioner on endogenous enzymatic activities within the hybrid layer (HL) created by a self-etch or an etch-and-rinse adhesive after 1 y. The activity within the HL was examined using in situ zymography and confocal laser scanning microscopy after 24 h or 1-y storage in artificial saliva. Dentin specimens were bonded with Clearfil SE Bond (CSE) or XP Bond (XPB). For CSE, the self-etching primer was applied and treated with 0.3 M EDC for 1 min, and then the bonding agent was applied. For XPB, dentin was etched and treated with 0.3 M EDC for 1 min and then bonded with the primer-bonding agent. Control specimens were prepared without EDC treatment. Slices containing the adhesive-dentin interface were covered with fluorescein-conjugated gelatin and observed with a multiphoton confocal microscope. Fluorescence intensity emitted by hydrolyzed fluorescein-conjugated gelatin was quantified, and the amount of gelatinolytic activity was represented by the percentage of green fluorescence emitted within the HL. After 24 h of storage, enzymatic activity was detected by in situ zymography within the HLs of both tested adhesives, with XPB higher than CSE ( P < 0.05). Almost no fluorescence signal was detected when specimens were pretreated with EDC compared to controls ( P < 0.05). After 1 y of storage, enzymatic activities significantly increased for all groups (excluding XPB control) compared to 24-h storage ( P < 0.05), with EDC pretreated specimens exhibiting significantly lower activity than controls ( P < 0.05). The present study showed, for the first time, that the use of EDC for both the self-etch and the etch-and-rinse approaches results in the reduction but not complete inhibition of matrix-bound collagenolytic enzyme activities over time in the HL.
盐酸 1-乙基-3-(3-二甲基氨基丙基)碳二亚胺（EDC）最近被研究用于防止胶原随时间降解，并提高树脂-牙本质粘结耐久性。本研究的目的是评估 0.3 M EDC 处理剂对自酸蚀或酸蚀-冲洗粘结体系形成的混合层（HL）内内源性酶活性的影响，1 年后的情况。在人工唾液中 24 h 或 1 年储存后，通过原位酶谱法和共聚焦激光扫描显微镜检查 HL 内的活性。用 Clearfil SE Bond（CSE）或 XP Bond（XPB）粘结牙本质标本。对于 CSE，应用自酸蚀底漆并用 0.3 M EDC 处理 1 min，然后应用粘结剂。对于 XPB，用 0.3 M EDC 处理牙本质 1 min 并用底漆-粘结剂粘结。制备不含 EDC 处理的对照标本。用荧光素标记明胶覆盖含有粘结-牙本质界面的切片，并用多光子共聚焦显微镜观察。用共聚焦激光扫描显微镜定量分析水解荧光素标记明胶产生的荧光强度，用 HL 内发出的绿色荧光的百分比表示明胶酶活性。储存 24 h 后，两种测试粘结剂的 HL 内均通过原位酶谱法检测到酶活性，XPB 高于 CSE（P<0.05）。与对照组相比，用 EDC 预处理标本几乎检测不到荧光信号（P<0.05）。储存 1 年后，与 24 h 储存相比，所有组（除 XPB 对照组外）的酶活性均显著增加（P<0.05），用 EDC 预处理标本的活性明显低于对照组（P<0.05）。本研究首次表明，对于自酸蚀和酸蚀-冲洗两种方法，使用 EDC 可随时间减少，但不能完全抑制 HL 内结合的胶原酶活性。
