Eliades George, Mantzourani Maria, Labella Roberto, Mutti Bruna, Sharma Deepak
Department of Biomaterials, University of Athens, School of Dentistry, Greece.
J Dent. 2013 Jul;41 Suppl 4:S28-39. doi: 10.1016/S0300-5712(13)70004-6.
To evaluate the effect of desensitising agents on human dentine morphology and composition.
Randomly assigned human coronal-dentine specimens were subjected to: (a) no treatment (smear-layer control, n=4); (b) acid etching with 6% citric acid (demineralised control, n=4); (c) treatment with desensitising agents (12 cycles of 60 s treatment with 60 s between-treatment rinsing, n=6 per agent); and (d) exposure to acidic challenge (pH 5.0 for 90 s, n=6 per agent). The tested products were: Listerine® Advanced Defence Sensitive (LADS; 1.4% potassium oxalate) mouthrinse, Colgate® Sensitive Pro-Relief™ mouthrinse, and toothpaste slurries (paste/water 1:2 wt/wt ratio) of Colgate® Sensitive Pro-Relief™ paste, Crest® Sensitive paste and Sensodyne® Repair and Protect paste. All dentine surfaces were studied by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, Raman microscopy and high vacuum scanning electron microscopy with energy-dispersive X-ray microanalysis (HV-SEM/EDX).
Desensitising slurry treatments occluded tubule orifices of acid-etched dentine, creating a randomly distributed surface pattern of particle aggregates. The greatest intratubular penetration of occluding particles was found in dentine treated with LADS. The atomic ratios of Ca/N and Ca/P, and the mineral/matrix ratios increased after toothpaste-slurry treatments compared with the acid-etched dentine. However, the acidic challenge removed most surface precipitates and further demineralised these substrates. Before the acidic challenge, the surface features were least affected in specimens treated with Sensodyne® Repair and Protect. After the acidic challenge, the sub-surface occlusion features were least affected in specimens treated with LADS.
Although most tested products achieved occlusion of dentinal tubules and provided evidence of mineral deposits, the deposit formed by LADS demonstrated the greatest resistance to acidic challenge, which simulates intra-oral demineralisation phases.
评估脱敏剂对人牙本质形态和成分的影响。
将随机分配的人牙冠部牙本质标本进行如下处理：(a) 不做处理（涂抹层对照，n = 4）；(b) 用6%柠檬酸进行酸蚀（脱矿质对照，n = 4）；(c) 用脱敏剂处理（60秒处理12个循环，每次处理间隔60秒冲洗，每种试剂n = 6）；以及(d) 暴露于酸性刺激（pH 5.0，90秒，每种试剂n = 6）。测试产品包括：李施德林®高级防护敏感（LADS；1.4%草酸钾）漱口水、高露洁®敏感专业舒缓™漱口水，以及高露洁®敏感专业舒缓™牙膏、佳洁士®敏感牙膏和舒适达®修复与保护牙膏的牙膏浆液（膏体/水重量比1:2）。所有牙本质表面均通过衰减全反射傅里叶变换红外（ATR - FTIR）光谱、拉曼显微镜以及带有能量色散X射线微分析的高真空扫描电子显微镜（HV - SEM/EDX）进行研究。
脱敏浆液处理封闭了酸蚀牙本质的小管口，形成了颗粒聚集体随机分布的表面图案。在用LADS处理的牙本质中发现封闭颗粒在小管内的渗透最深。与酸蚀牙本质相比，牙膏浆液处理后钙/氮和钙/磷的原子比以及矿物质/基质比增加。然而，酸性刺激去除了大部分表面沉淀物并使这些底物进一步脱矿质。在酸性刺激之前，用舒适达®修复与保护处理的标本表面特征受影响最小。在酸性刺激之后，用LADS处理的标本亚表面封闭特征受影响最小。
尽管大多数测试产品实现了牙本质小管的封闭并提供了矿物质沉积的证据，但LADS形成的沉积物对酸性刺激表现出最大的抗性，酸性刺激模拟了口腔内的脱矿质阶段。
