Uşümez Serdar, Orhan Metin, Uşümez Aslihan
Faculty of Dentistry, Department of Orthodontics, Selçuk University, Konya 42079, Turkey.
Am J Orthod Dentofacial Orthop. 2002 Dec;122(6):649-56. doi: 10.1067/mod.2002.127294.
Irradiation of enamel with laser energy changes the physical and chemical characteristics of the enamel surface, and these alterations hold promise for the conditioning of enamel for bonding procedures. This laboratory study examined the influence of laser irradiation of enamel at 2 different power settings with an erbium, chromium: yttrium, scandium, gallium, garnet (Er,Cr:YSGG) hydrokinetic laser system (Millennium System, Biolase Technology, Inc; San Clemente, Calif) on the shear bond strength of orthodontic appliances and compared these with that of acid-etching. The prepared surfaces of 40 noncarious, intact, extracted premolars were exposed to laser energy: 20 teeth at 2-W setting (5.6 J/cm(2)) and 20 teeth at 1-W setting (2.7 J/cm(2)) of the commercial laser unit. Twenty teeth were etched with 37% orthophosphoric acid. Brackets were bonded with an orthodontic no-mix adhesive, and shear bond strength was determined with a universal testing machine. Data were analyzed with Kruskal-Wallis and Mann-Whitney U tests. Etched and restored surfaces of an acid-etched tooth and a 2-W laser-irradiated tooth were examined with scanning electron microscopy (SEM). Laser treatment under 2 W resulted in bond strengths of 7.11 +/- 4.56 megapascals (MPa), which was not significantly different from that of acid etching (8.23 +/- 2.30 MPa). Laser irradiation at 1 W resulted in bond strengths of 5.64 +/- 3.19 MPa, which was significantly different from that of acid etching (P <.05). However, large SD and coefficient of variation values of both laser groups made reliability of this method as an enamel conditioner questionable. Scanning electron microscopy studies of the restored irradiated surfaces showed good surface characteristics, whereas the lased surface was still more irregular than the restored acid-etched sample. Although laser devices are effectively used in some other areas of dentistry, enamel conditioning with an Er,Cr:YSGG laser cannot be considered a successful alternative to the conventional methods of increasing bond strengths to enamel.
用激光能量照射牙釉质会改变牙釉质表面的物理和化学特性，这些改变有望用于牙釉质预处理以进行粘接操作。这项实验室研究考察了使用铒铬：钇钪镓石榴石（Er,Cr:YSGG）水动力激光系统（Millennium System，Biolase Technology公司；加利福尼亚州圣克莱门特）在2种不同功率设置下对牙釉质进行激光照射对正畸矫治器剪切粘结强度的影响，并将其与酸蚀的效果进行比较。40颗无龋、完整的拔除前磨牙的制备表面接受激光能量照射：20颗牙在商用激光装置的2瓦设置（5.6 J/cm(2)）下照射，20颗牙在1瓦设置（2.7 J/cm(2)）下照射。20颗牙用37%的正磷酸进行酸蚀。用正畸非混合粘结剂粘结托槽，并用万能试验机测定剪切粘结强度。数据用Kruskal-Wallis和Mann-Whitney U检验进行分析。用扫描电子显微镜（SEM）检查酸蚀牙和2瓦激光照射牙的蚀刻和修复表面。2瓦功率下的激光处理产生的粘结强度为7.11±4.56兆帕（MPa），与酸蚀的粘结强度（8.23±2.30 MPa）无显著差异。1瓦功率下的激光照射产生的粘结强度为5.64±3.19 MPa，与酸蚀的粘结强度有显著差异（P<.05）。然而，两个激光组的标准差和变异系数都很大，使得这种方法作为牙釉质预处理方法的可靠性受到质疑。对修复后的照射表面进行的扫描电子显微镜研究显示出良好的表面特性，而激光照射表面仍比修复后的酸蚀样本更不规则。尽管激光设备在牙科的其他一些领域得到了有效应用，但用Er,Cr:YSGG激光进行牙釉质预处理不能被视为增加牙釉质粘结强度的传统方法的成功替代方法。
