Faculty of Dentistry, Oral and Craniofacial Sciences, King's College London, London, UK; Department of Restorative Dental Science, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia.
Faculty of Dentistry, Oral and Craniofacial Sciences, King's College London, London, UK; Department of Prosthodontics, University of Melbourne, Melbourne, Australia.
Dent Mater. 2022 Jun;38(6):1030-1043. doi: 10.1016/j.dental.2022.04.005. Epub 2022 Apr 23.
The tooth-resin composite interface is frequently associated with failure because of microbial contamination, hydrolytic and collagenolytic degradation. Thus, designing a dentine bonding system (DBS) with an intrinsically antimicrobial polymerisable monomer is of significance especially if it can be used with self-etching primers enabling resistance to degradation of the interface.
Experimental adhesives were developed incorporating eugenyl methacrylate (EgMA) at concentrations of 0,10 or 20 wt%, designated as EgMA0, EgMA10 and EgMA20, respectively, for use as a two-step self-etch DBS with the functional monomer bis[2-(methacryloyloxy) ethyl] phosphate (BMEP) in the primer. The curing, thermal and wettability properties of the adhesives were determined, and hybrid layer formation was characterised by confocal laser scanning microscopy, microtensile bond strengths (µTBS) and nanoleakage by back-scattered SEM. In situ zymography was used to assess MMP inhibitory activity of the BMEP-EgMA DBS.
EgMA in the adhesives lowered the polymerisation exotherm and resulted in higher Tg, without negatively affecting degree of conversion. Water sorption and solubility were significantly lower with higher concentrations of EgMA in the adhesive. The formation of a distinct hybrid layer was evident from confocal images with the different adhesives, whilst EgMA20 yielded the highest µTBS post water storage challenges and lowest nanoleakage after 6 months. The experimental DBS exhibited minimal to no MMP activity at 3 months.
The hydrophobic nature of EgMA and high cross-link density exerts considerable benefits in lowering water uptake and polymerisation exotherm. The application of EgMA, adhesives in conjunction with BMEP in a multi-functional self-etching DBS can resist MMP activity, hence, enhance longevity of the dentine-resin composite interface.
由于微生物污染、水解和胶原降解，牙-树脂复合界面经常发生故障。因此，设计一种具有内在抗菌可聚合单体的牙本质粘结系统（DBS）具有重要意义，特别是如果它可以与自酸蚀底漆一起使用，从而能够抵抗界面的降解。
开发了实验性胶粘剂，其中包含浓度为 0、10 或 20wt%的丁香基甲基丙烯酸酯（EgMA），分别命名为 EgMA0、EgMA10 和 EgMA20，用于与功能性单体双[2-（甲基丙烯酰氧基）乙基]磷酸酯（BMEP）作为两步自酸蚀 DBS 在底漆中使用。测定了胶粘剂的固化、热和润湿性性能，并通过共焦激光扫描显微镜、微拉伸粘结强度（µTBS）和背散射 SEM 纳米泄漏来表征混合层形成。原位酶谱法用于评估 BMEP-EgMA DBS 的 MMP 抑制活性。
胶粘剂中的 EgMA 降低了聚合放热，并导致更高的 Tg，而不会对转化率产生负面影响。随着胶粘剂中 EgMA 浓度的增加，吸水率和溶解度显著降低。不同胶粘剂的共焦图像显示出明显的混合层形成，而 EgMA20 在水储存挑战后产生了最高的µTBS 和 6 个月后最低的纳米泄漏。实验性 DBS 在 3 个月时表现出最小至无 MMP 活性。
EgMA 的疏水性和高交联密度在降低吸水率和聚合放热方面具有相当大的优势。EgMA、胶粘剂与 BMEP 在多功能自酸蚀 DBS 中的应用可以抵抗 MMP 活性，从而提高牙本质-树脂复合材料界面的耐久性。
