Unit-Division of Dental Student Training and Patient Care, Medical University of Vienna, Vienna, Austria.
Lasers Med Sci. 2012 Jul;27(4):717-22. doi: 10.1007/s10103-011-0963-5. Epub 2011 Jul 20.
The bond joint between dentin and ceramic is a critical determinant in prosthodontic dentistry. The laser is an alternative to the diamond bur for preparing tooth cavities. However, the impact of lasers on the bond between the laser-irradiated dentin and the ceramic remains a matter of controversy. We determined the shear strength of bonds between ceramic blocks and human dentin discs prepared with either an Er,Cr:YSGG laser or a diamond bur. A total of 180 dentin discs were randomly assigned to four groups. Three groups of discs were prepared with the Er,Cr:YSGG laser irradiation (2 W, 30 Hz, 50% H(2)O, 70% air) and the fourth group was prepared with a diamond bur. In one of the laser groups the discs surfaces were also treated with phosphoric acid and in another with phosphoric acid and mechanical smoothing using a dental excavator. The ceramic blocks were bonded to the dentin discs with Syntac adhesive (together with Variolink II curing system), ExciTE adhesive (together with Variolink II curing system) or RelyX self-adhesive cement. The shear strength of the bond between ceramic and dentin was significantly higher following dentin surface treatment with the laser alone than following treatment with the diamond bur and Variolink II/Syntac (p = 0.021) but not significantly higher than following treatment with the diamond bur and Variolink II/ExciTE (p = 0.138) or RelyX (p = 0.150). A significant difference was not observed when the laser-treated dentin was conditioned with phosphoric acid and mechanical smoothing. These findings demonstrate that the bond between dentin and ceramic may be stronger after laser irradiation; however, the selection of the adhesive material is an additional factor that affects the bond strength.
牙本质和陶瓷之间的粘结是修复牙科的关键决定因素。激光是替代牙钻制备牙洞的一种方法。然而，激光对激光照射牙本质和陶瓷之间粘结的影响仍然存在争议。我们确定了用 Er，Cr：YSGG 激光或牙钻制备的陶瓷块与人牙本质盘之间粘结的剪切强度。总共 180 个牙本质盘随机分为四组。三组牙本质盘用 Er，Cr：YSGG 激光照射（2 W，30 Hz，50％H 2 O，70％空气）制备，第四组用牙钻制备。在激光组中的一组中，牙本质盘表面还经过磷酸处理，另一组用磷酸处理并用牙挖器进行机械平滑处理。陶瓷块用 Syntac 胶（与 Variolink II 固化系统一起）、ExciTE 胶（与 Variolink II 固化系统一起）或 RelyX 自粘水泥粘结到牙本质盘上。与仅用激光处理相比，用牙钻和 Variolink II/Syntac 处理（p = 0.021）或与牙钻和 Variolink II/ExciTE（p = 0.138）或 RelyX（p = 0.150）处理后，陶瓷和牙本质之间粘结的剪切强度显著更高。当激光处理的牙本质用磷酸和机械平滑处理时，没有观察到显著差异。这些发现表明，激光照射后牙本质和陶瓷之间的粘结可能更强；然而，粘结材料的选择是影响粘结强度的另一个因素。
