Daood Umer, Swee Heng Chan, Neo Chiew Lian Jennifer, Fawzy Amr S
Discipline of Oral Sciences, Faculty of Dentistry, National University of Singapore, Singapore, Singapore.
Laboratory technologist, Discipline of Oral Sciences, Biomaterials and Biophotonics, National University of Singapore, Singapore, Singapore.
Int J Oral Sci. 2015 Jun 26;7(2):110-24. doi: 10.1038/ijos.2014.49.
To modify two-step experimental etch-and-rinse dentin adhesive with different concentrations of riboflavin and to study its effect on the bond strength, degree of conversion, along with resin infiltration within the demineralized dentin substrate, an experimental adhesive-system was modified with different concentrations of riboflavin (m/m, 0, 1%, 3%, 5% and 10%). Dentin surfaces were etched with 37% phosphoric acid, bonded with respective adhesives, restored with restorative composite-resin, and sectioned into resin-dentin slabs and beams to be stored for 24 h or 9 months in artificial saliva. Micro-tensile bond testing was performed with scanning electron microscopy to analyse the failure of debonded beams. The degree of conversion was evaluated with Fourier transform infrared spectroscopy (FTIR) at different time points along with micro-Raman spectroscopy analysis. Data was analyzed with one-way and two-way analysis of variance followed by Tukey's for pair-wise comparison. Modification with 1% and 3% riboflavin increased the micro-tensile bond strength compared to the control at 24 h and 9-month storage with no significant differences in degree of conversion (P<0.05). The most predominant failure mode was the mixed fracture among all specimens except 10% riboflavin-modified adhesive specimens where cohesive failure was predominant. Raman analysis revealed that 1% and 3% riboflavin adhesives specimens showed relatively higher resin infiltration. The incorporation of riboflavin in the experimental two-step etch-and-rinse adhesive at 3% (m/m) improved the immediate bond strengths and bond durability after 9-month storage in artificial saliva without adversely affecting the degree of conversion of the adhesive monomers and resin infiltration.
用不同浓度的核黄素对两步法实验性酸蚀冲洗牙本质黏结剂进行改性，并研究其对黏结强度、转化率以及脱矿牙本质基质内树脂渗透的影响。用不同浓度（质量/质量，0、1%、3%、5%和10%）的核黄素对一种实验性黏结系统进行改性。牙本质表面用37%的磷酸酸蚀，用相应的黏结剂黏结，用复合树脂修复，然后切成树脂-牙本质薄片和梁，在人工唾液中储存24小时或9个月。通过扫描电子显微镜进行微拉伸黏结测试，以分析脱黏梁的破坏情况。在不同时间点用傅里叶变换红外光谱（FTIR）以及显微拉曼光谱分析评估转化率。数据用单向和双向方差分析，随后用Tukey法进行两两比较。与对照组相比，在24小时和9个月储存期时，用1%和3%核黄素改性可提高微拉伸黏结强度，转化率无显著差异（P<0.05）。除10%核黄素改性黏结剂标本以内聚破坏为主外，所有标本中最主要的破坏模式是混合破坏。拉曼分析显示，1%和3%核黄素黏结剂标本显示出相对较高的树脂渗透。在实验性两步酸蚀冲洗黏结剂中加入3%（质量/质量）的核黄素可提高人工唾液中储存9个月后的即时黏结强度和黏结耐久性，且不会对黏结单体的转化率和树脂渗透产生不利影响。
