将葡萄籽提取物原花青素(proanthocyanidin,PA)分别用乙醇、丙酮、蒸馏水配制成不同浓度的预处理剂,利用傅里叶红外光谱测试PA预处理对Single Bond 2和Prime&Bond NT两种全酸蚀粘接系统双键转化率的影响。结果发现不同溶剂、浓度的PA预处理剂组2种全酸蚀粘接剂的双键转化率与阴性对照组均无统计学差异(P>0.05)。提示原花青素预处理对全酸蚀粘接系统固化性能无显著影响。
目的:探讨富含原花青素的葡萄籽提取物(grape seed extract,GSE)对两步法自酸蚀粘接系统即刻粘接性能的影响。方法:红外光谱测试不同浓度GSE预处理剂处理不同时间对Clearfil SE Bond双键转化率的作用,筛选最佳处理时间用于即刻微拉伸粘接强度测试,场发射扫描电镜观察断裂模式。结果:GSE浓度对双键转化率无显著影响,预处理40s组最高。各组间粘接强度无统计学差异,3%GSE组最高,以混合断裂为主。结论:3%GSE预处理40s可在不影响双键转化率的前提下一定程度上提高即刻粘接强度。
目的:探讨葡萄籽提取物(grape seed extract,GSE)短暂预处理脱矿牙本质对其极限拉伸强度及树脂-牙本质即刻微拉伸粘接强度的影响。方法:以乙醇、丙酮、蒸馏水为溶剂配制不同浓度的GSE溶液,以溶剂为空白对照,无预处理为阴性对照,5%戊二醛为阳性对照,每组样本15例。GSE预处理脱矿牙本质后,测试牙本质极限拉伸强度及树脂-牙本质微拉伸粘接强度,观察粘接断裂面微观形貌并分析断裂模式。结果:GSE预处理组牙本质极限拉伸强度均呈浓度和时间依赖性增加。应用Single Bond 2粘接时,无论何种溶剂,10%或15%GSE预处理组微拉伸粘接强度显著高于空白对照组(P<0.05);而用Prime&Bond NT粘接时,仅15%GSE水溶剂组和10%GSE丙酮溶剂组微拉伸粘接强度显著高于空白对照组(P<0.05)。交联预处理对水和乙醇溶剂的Single Bond 2粘接时微拉伸粘接强度的改善作用比用水和丙酮溶剂的Prime&Bond NT粘接时更为显著。粘接试件断裂均以混合破坏为主,预处理组试件断裂多发生在混合层顶部,而阴性和空白对照组断裂多位于混合层底部。结论:GSE短暂预处理脱矿牙本质可改善其机械性能,增强混合层,并提高树脂-牙本质即刻微拉伸粘接强度。
Our previous studies showed that biomodification of demineralized dentin collagen with proanthocyanidin(PA) for a clinically practical duration improves the mechanical properties of the dentin matrix and the immediate resin–dentin bond strength. The present study sought to evaluate the ability of PA biomodification to reduce collagenase-induced biodegradation of demineralized dentin matrix and dentin/adhesive interfaces in a clinically relevant manner. The effects of collagenolytic and gelatinolytic activity on PA-biomodified demineralized dentin matrix were analysed by hydroxyproline assay and gelatin zymography. Then, resin-/dentin-bonded specimens were prepared and challenged with bacterial collagenases. Dentin treated with 2% chlorhexidine and untreated dentin were used as a positive and negative control, respectively. Collagen biodegradation, the microtensile bond strengths of bonded specimens and the micromorphologies of the fractured interfaces were assessed. The results revealed that both collagenolytic and gelatinolytic activity on demineralized dentin were notably inhibited in the PA-biomodified groups, irrespective of PA concentration and biomodification duration. When challenged with exogenous collagenases, PA-biomodified bonded specimens exhibited significantly less biodegradation and maintained higher bond strengths than the untreated control. These results suggest that PA biomodification was effective at inhibiting proteolytic activity on demineralized dentin matrix and at stabilizing the adhesive/dentin interface against enzymatic degradation, is a new concept that has the potential to improve bonding durability.
