Department of Biomedical and Neuromotor Sciences, DIBINEM, University of Bologna - Alma Mater Studiorum, Via San Vitale 59, 40125, Bologna, Italy.
Department of Restorative Dentistry, School of Dentistry, University of São Paulo, Av. Prof. Lineu Prestes 2227, 05508-000, São Paulo, Brazil.
J Dent. 2019 May;84:60-66. doi: 10.1016/j.jdent.2019.03.004. Epub 2019 Mar 12.
The aim of this study was to investigate, by the means of microtensile bond strength (μTBS) test, gelatin and in situ zymography, the influence of 0.2% CHX contained within a commercially available adhesive on long-term bond strength and endogenous enzymatic activity.
Non-carious teeth were subjected to μTBS test (N = 15 for each group) and stressed until failure. μTBS was evaluated immediately and after 12-month storage in artificial saliva at 37 °C. Dentin powder was obtained from additional teeth (N = 7) for gelatin zymography, while for in situ zymography, 3 teeth for each group were selected. Gelatin and in situ zymography were performed in dentin powder and slices of dentin, respectively, to assess the ability of 0.2% CHX blended within the adhesive to inhibit endogenous enzymatic activity.
μTBS bond strength was higher in the CHX-containing groups, immediately as well as after aging. The bond strength significantly decreased after 12-month aging. The activation of endogenous MMPs was found to be related to the presence of CHX within the adhesive system and the bonding strategy employed.
Under this perspective 0.2% CHX blended within Peak Universal adhesive monomer seems to increase immediate bond strength, to preserve bond strength over time and to efficiently inhibit endogenous enzymatic activity in dentin. Hence, blending the CHX in low concentrations within the adhesive could be recommended as a feasible technique in every-day clinical practice.
Using CHX-containing adhesives could be recommended due to several benefits: it seems to increase the longevity of the hybrid layer; the inhibitor appears to be efficiently delivered to the dentinal substrate and to inhibit endogenous enzymatic activity, without prolonging chair time.
本研究旨在通过微拉伸结合强度（μTBS）测试、明胶和原位酶谱分析，研究商业上可用的胶粘剂中含有的 0.2%洗必泰对长期结合强度和内源性酶活性的影响。
非龋牙进行 μTBS 测试（每组各 15 个牙），直至破坏。立即评估 μTBS，并在 37°C 的人工唾液中储存 12 个月后再次评估。从额外的牙齿（每组 7 个）中获得牙本质粉进行明胶酶谱分析，而对于原位酶谱分析，每组选择 3 个牙齿。分别在牙本质粉和牙本质切片中进行明胶和原位酶谱分析，以评估 0.2%洗必泰混合在胶粘剂中抑制内源性酶活性的能力。
含 0.2%洗必泰的组即刻和老化后 μTBS 结合强度更高。12 个月老化后，结合强度显著下降。发现内源性 MMPs 的激活与胶粘剂系统内的 CHX 存在和所采用的粘接策略有关。
从这个角度来看，在 Peak Universal 胶粘剂单体中混合 0.2%的洗必泰似乎可以提高即刻结合强度，随着时间的推移保持结合强度，并有效地抑制牙本质中的内源性酶活性。因此，将 CHX 以低浓度混合在胶粘剂中可能被推荐为日常临床实践中的一种可行技术。
由于有多种益处，使用含 CHX 的胶粘剂可能是合理的：它似乎可以增加混合层的耐久性；抑制剂似乎可以有效地输送到牙本质基底并抑制内源性酶活性，而不会延长椅旁时间。
