Centrer for Innovative Clinical Medicine, Okayama University Hospital, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan.
Advanced Research Center for Oral and Craniofacial Sciences, Okayama University Dental School, Okayama, Japan.
Dent Mater. 2017 Mar;33(3):e124-e135. doi: 10.1016/j.dental.2016.12.003. Epub 2017 Jan 2.
CAD-CAM blocks to fabricate semi-direct and indirect restorations are available in different sorts of ceramics as well as composite. In order to bond restorations prepared out of composite blocks into tooth cavities, it is recommended to gently sandblast the surface prior to the application of a primer/adhesive. Today, the effect of sandblasting composite block surfaces has not thoroughly been investigated. In this study, the ultra-structure of composite CAD-CAM blocks was investigated with special attention to the effect of sandblasting on the surface topography and of silanization on the bonding performance.
Five different composite CAD-CAM blocks were involved. We correlatively investigated their structural and chemical composition using X-ray diffraction (XRD), energy dispersion spectroscopy (EDS), scanning electron microscopy (SEM) and (scanning) transmission electron microscopy ((S)TEM). The effect of sandblasting was also imaged in cross-section and at the interface with composite cement. Finally, we measured the shear bond strength to the sandblasted block surface with and without silanization.
All composite blocks revealed a different ultra-structure. Sandblasting increased surface roughness and resulted in an irregular surface with some filler exposure. Sandblasting also damaged the surface. When the sandblasted composite blocks were silanized, superior bonding receptiveness in terms of higher bond strength was achieved except for Shofu Block HC.
Sandblasting followed by silanization improved the bond strength to composite CAD-CAM blocks. However, sandblasting may also damage the composite CAD-CAM block surface. For the composite CAD-CAM block Shofu Block HC, the damage was so severe that silanization did not improve bond strength.
可用于制造半直接和间接修复体的 CAD-CAM 块可采用不同种类的陶瓷和复合材料制成。为了将由复合材料块制备的修复体粘结到牙腔中，建议在应用底漆/粘合剂之前，轻轻喷砂表面。如今，复合材料 CAD-CAM 块表面喷砂的效果尚未得到充分研究。在这项研究中，特别关注了喷砂对表面形貌的影响以及硅烷化对粘结性能的影响，对复合材料 CAD-CAM 块的超微结构进行了研究。
涉及了五种不同的复合材料 CAD-CAM 块。我们使用 X 射线衍射（XRD）、能量色散光谱（EDS）、扫描电子显微镜（SEM）和（扫描）透射电子显微镜（（S）TEM）对其结构和化学成分进行了相关研究。还对喷砂对复合材料粘结剂的界面和横截面的影响进行了成像。最后，我们测量了喷砂块表面未经硅烷化和硅烷化后的剪切粘结强度。
所有复合材料块均显示出不同的超微结构。喷砂增加了表面粗糙度，导致表面不规则，一些填充物暴露在外。喷砂还损坏了表面。当喷砂后的复合材料块进行硅烷化处理时，除了 Shofu Block HC 外，粘结接受性得到了改善，表现为粘结强度更高。
喷砂后硅烷化处理提高了复合材料 CAD-CAM 块的粘结强度。然而，喷砂也可能损坏复合材料 CAD-CAM 块的表面。对于复合材料 CAD-CAM 块 Shofu Block HC，损坏非常严重，硅烷化处理未能提高粘结强度。
