Santini A, Mitchell S
University of Edinburgh, Scotland.
Quintessence Int. 1998 Nov;29(11):737-47.
The purpose of this study was to investigate the effect of conditioners on smear layers produced by different bur types and rotational speeds and to study the interaction of subsequently applied primer and sealer with these conditioned surfaces.
Smear layers were produced on human teeth immediately after extraction by burs rotating at approximately 6,000 rpm without water spray and 400,000 rpm with water spray. Gluma CPS etchant was applied for 15, 30, and 60 seconds, and a 20% phosphoric acid liquid (control) was applied for 30 seconds to smear layers. The specimens were prepared by critical point drying for scanning electron microscopic imaging within 24 hours. Additional specimens were prepared and treated with Gluma CPS primer and sealer, according to the manufacturer's instructions.
There were only small variations in the smear layer thicknesses with different bur types or speeds of rotation. Gluma CPS conditioner, applied for the recommended times, did not completely remove the smear layer. An altered smear layer, composed of a reaction product, remained on the dentinal surface. A zone of demineralization did occur, however, beneath the partially removed smear layer in both the 15- and 30-second specimens but was only partly filled by primer and sealer. Smear layers were completely removed by the 20% phosphoric acid liquid to expose a delicate collagen network.
An understanding of the appropriate treatment for smear layers is crucial to the development of improved dentin bonding systems.
本研究旨在调查调节剂对不同车针类型和转速产生的玷污层的影响，并研究随后应用的底漆和封闭剂与这些经处理表面的相互作用。
在人牙拔除后立即使用车针制备玷污层，车针转速分别为约6000转/分钟且无喷水和400000转/分钟且有喷水。将Gluma CPS蚀刻剂分别应用15、30和60秒，将20%磷酸液（对照）应用30秒于玷污层。标本通过临界点干燥制备，以便在24小时内进行扫描电子显微镜成像。根据制造商说明制备额外的标本，并用Gluma CPS底漆和封闭剂进行处理。
不同车针类型或转速下玷污层厚度仅有微小差异。按推荐时间应用的Gluma CPS调节剂未完全去除玷污层。由反应产物组成的改变的玷污层留在牙本质表面。然而，在15秒和30秒标本中，在部分去除的玷污层下方确实出现了脱矿区域，但仅部分被底漆和封闭剂填充。20%磷酸液完全去除了玷污层，暴露出精细的胶原网络。
了解玷污层的适当处理方法对于改进牙本质粘结系统的开发至关重要。
