Nakagaki Susumu, Iijima Masahiro, Endo Kazuhiko, Saito Takashi, Mizoguchi Itaru
Division of Orthodontics and Dentofacial Orthopedics, Department of Oral Growth and Development, School of Dentistry, Health Sciences University of Hokkaido.
Dent Mater J. 2015;34(3):287-93. doi: 10.4012/dmj.2014-225. Epub 2015 Apr 23.
We investigated the effects of CO2 laser irradiation combined with acidulated phosphate fluoride (APF) application on the demineralization of enamel. APF gel was applied to the buccal enamel of human premolars and CO2 laser was applied. After the specimens were immersed in demineralization solution for 72 h, they were subjected to depth-dependent micro-CT and nanoindentation analyses. Micro-X-ray diffraction and X-ray photoelectron spectroscopy were performed to analyze the surfaces. Some surface regions of the enamel in specimens that were laser-irradiated with low output and APF-treated showed significantly higher values of MD and hardness than specimens treated with APF alone. A higher fluoride concentration in the enamel surface was observed in specimens treated with CO2 laser irradiation plus APF gel application. In conclusion, CO2 laser irradiation with low output is preferable to improve acid resistance.
我们研究了二氧化碳激光照射联合应用酸化磷酸氟（APF）对牙釉质脱矿的影响。将APF凝胶应用于人类前磨牙的颊侧牙釉质，并进行二氧化碳激光照射。将标本浸泡在脱矿溶液中72小时后，对其进行深度相关的显微CT和纳米压痕分析。进行微X射线衍射和X射线光电子能谱分析以分析表面。低输出激光照射并经APF处理的标本中，牙釉质的一些表面区域显示出比仅用APF处理的标本更高的矿物质密度（MD）值和硬度。在应用二氧化碳激光照射加APF凝胶处理的标本中，观察到牙釉质表面的氟化物浓度更高。总之，低输出二氧化碳激光照射更有利于提高耐酸性。
