This study evaluated the effect of contamination with saliva or blood and different cleansing agents on the microtensile bond strength (μTBS) and in situ degree of conversion (DC in situ) of composite-adhesive interface. Sixty-six bovine incisors were ground flat to expose dentin and were randomly assigned to eleven groups (n = 6), according to the contaminant and the cleansing agent. A positive control (without contamination or cleansing agent) was determined. A multimode adhesive in the self-etching form was applied before contamination with blood or saliva. Then, the groups received different cleansing protocols that generated two negative controls (contaminated with saliva or blood and only air dried) and eight experimental groups, washed with water (H₂O), ascorbic acid (AscAc10%), hydrogen peroxide 3% (H₂O₂3%) and chlorhexidine 2% (CLX2%). Specimens were restored with composite resin and prepared for μTBS. After 24 h, restored teeth were sectioned and the sticks subjected to the μTBS test (in a universal testing machine at 0.5 mm/min speed). Degree of conversion within the hybrid layer (DC in situ) was evaluated by micro-Raman spectroscopy. Data were analysed using a two-way analysis of variance (ANOVA) and Tukey's test (p < 0.05). While saliva and cleansing agents did not affect μTBS and DC in situ (p > 0.05), blood influenced negatively (p = 0.025). However, CLX2% was able to re-establish the values of μTBS and DC in situ (p = 1.0). Weibull regression analysis of μTBS data confirmed the prior mentioned performance. Saliva and cleansing agents did not influence μTBS and DC in situ values, while blood caused them to be significantly decreased. CLX2% was able to reverse the negative effects of blood contamination. In this way, in case of composite-adhesive interface contamination with blood, CLX2% washing was able to reverse the μTBS and DC in situ values.

本研究评估了唾液或血液和不同清洁剂污染对复合粘合剂界面的微拉伸粘合强度 (μTBS) 和原位转化率 (DC in situ ) 的影响。将 66 颗牛门牙磨平以暴露牙本质，并 根据污染物和清洁剂随机分为 11 组（n = 6）。确定阳性对照（无污染或清洁剂）。在被血液或唾液污染之前，使用自蚀刻形式的多模式粘合剂。然后，各组接受不同的清洁方案，产生两个阴性对照（被唾液或血液污染，仅风干）和八个实验组，用水清洗（H₂ O)、抗坏血酸 (AscAc10%)、过氧化氢 3% (H ₂ O ₂ 3%) 和氯己定 2% (CLX2%)。用复合树脂修复标本并准备用于 μTBS。24 小时后，对修复的牙齿进行切片，并对棒进行 μTBS 测试（在万能试验机中，速度为 0.5 毫米/分钟）。通过微拉曼光谱评估混合层内的转化程度（DC原位）。使用双向方差分析 (ANOVA) 和 Tukey 检验 ( p  < 0.05) 分析数据。虽然唾液和清洁剂不会影响 μTBS 和 DC原位( p  > 0.05)，但血液会产生负面影响 ( p = 0.025）。然而，CLX2% 能够在原位重新建立 μTBS 和 DC 的值（p  = 1.0）。μTBS 数据的威布尔回归分析证实了前面提到的性能。唾液和清洁剂不影响 μTBS 和 DC原位值，而血液使它们显着降低。CLX2% 能够逆转血液污染的负面影响。这样，在复合粘合剂界面被血液污染的情况下，CLX2% 洗涤能够逆转 μTBS 和 DC原位值。