Department of Dental Materials, School of Dentistry, University of São Paulo, São Paulo, SP, Brazil.
Dent Mater. 2010 Apr;26(4):380-6. doi: 10.1016/j.dental.2009.12.009. Epub 2010 Jan 18.
Dentin bonding performed with hydrophobic resins using ethanol-wet bonding should be less susceptible to degradation but this hypothesis has never been validated.
This in vitro study evaluated stability of resin-dentin bonds created with an experimental three-step BisGMA/TEGDMA hydrophobic adhesive or a three-step hydrophilic adhesive after one year of accelerated aging in artificial saliva.
Flat surfaces in mid-coronal dentin were obtained from 45 sound human molars and randomly divided into three groups (n=15): an experimental three-step BisGMA/TEGDMA hydrophobic adhesive applied to ethanol (ethanol-wet bonding-GI) or water-saturated dentin (water-wet bonding-GII) and Adper Scotchbond Multi-Purpose [MP-GIII] applied, according to manufacturer instructions, to water-saturated dentin. Resin composite crowns were incrementally formed and light-cured to approximately 5mm in height. Bonded specimens were stored in artificial saliva at 37 degrees C for 24h and sectioned into sticks. They were subjected to microtensile bond test and TEM analysis immediately and after one year. Data were analyzed with two-way ANOVA and Tukey tests.
MP exhibited significant reduction in microtensile bond strength after aging (24h: 40.6+/-2.5(a); one year: 27.5+/-3.3(b); in MPa). Hybrid layer degradation was evident in all specimens examined by TEM. The hydrophobic adhesive with ethanol-wet bonding preserved bond strength (24h: 43.7+/-7.4(a); one year: 39.8+/-2.7(a)) and hybrid layer integrity, with the latter demonstrating intact collagen fibrils and wide interfibrillar spaces.
Coaxing hydrophobic resins into acid-etched dentin using ethanol-wet bonding preserves resin-dentin bond integrity without the adjunctive use of MMPs inhibitors and warrants further biocompatibility and patient safety's studies and clinical testing.
使用乙醇润湿粘结的疏水性树脂进行牙本质粘结，应该不易降解，但这一假设从未得到验证。
本体外研究评估了在人工唾液中加速老化一年后，使用实验性三步 BisGMA/TEGDMA 疏水性胶粘剂或三步亲水性胶粘剂形成的树脂-牙本质粘结的稳定性。
从 45 颗健康的人磨牙中获得中部牙本质的平面表面，并随机分为三组（n=15）：应用实验性三步 BisGMA/TEGDMA 疏水性胶粘剂于乙醇（乙醇润湿粘结-GI）或水饱和牙本质（水润湿粘结-GII），或根据制造商的说明，将 Adper Scotchbond Multi-Purpose [MP-GIII] 应用于水饱和牙本质。将树脂复合冠分层形成并光固化至大约 5mm 高。粘结试件在 37°C 的人工唾液中储存 24h 并切成棒状。立即和一年后，对它们进行微拉伸粘结试验和 TEM 分析。数据采用双因素方差分析和 Tukey 检验进行分析。
MP 在老化后（24h：40.6+/-2.5(a)；1 年：27.5+/-3.3(b)；MPa）微拉伸粘结强度显著降低。所有经 TEM 检查的标本均显示混合层降解。使用乙醇润湿粘结的疏水性胶粘剂保持粘结强度（24h：43.7+/-7.4(a)；1 年：39.8+/-2.7(a)）和混合层完整性，后者显示完整的胶原纤维和宽的纤维间空间。
使用乙醇润湿粘结将疏水性树脂引入酸蚀牙本质中，可以在不使用 MMPs 抑制剂的情况下保留树脂-牙本质粘结的完整性，值得进一步进行生物相容性和患者安全性研究和临床测试。
