Youssef M N, Youssef F A, Souza-Zaroni W C, Turbino M L, Vieira M M F
Department of Restorative Dentistry, School of Dentistry, University of São Paulo, Brazil.
Int J Paediatr Dent. 2006 Sep;16(5):342-7. doi: 10.1111/j.1365-263X.2006.00751.x.
The aim of this in vitro study was to evaluate the microleakage in occlusal surfaces, after preparation with Er:YAG laser and compared to the diamond-bur conventional technique.
Thirty premolars were divided into three groups: I - high-speed handpiece + 37% phosphoric acid; II - Er:YAG laser (350 mJ, 4 Hz and 112 J/cm(2)) + 37% phosphoric acid; and III - Er:YAG laser (350 mJ, 4 Hz and 112 J/cm(2)) + Er:YAG laser (80 mJ, 4 Hz, and 25 mJ/cm(2)). All cavities received the same adhesive system and were restored with flowable composite according to manufacturer's instructions. Teeth were submitted to thermal cycling and immersed in 50% silver nitrate solutions for 8 h in total darkness. Specimens were sectioned longitudinally in the bucco-lingual direction, in slices of 1 mm thick. Each slice was immersed into photo developing solution and was photographed, and microleakage was scored from 0 to 7, by three calibrated examiners.
A statistically significant difference (P < 0.0001) was observed between Er:YAG laser prepared and etched specimens and those in the other groups.
It can be concluded that no significant difference was noted between the two types of enamel preparation when etching was performed. Preparing and treating the enamel surface exclusively by Er:YAG laser resulted in the highest degree of leakage.
本体外研究的目的是评估用铒激光制备咬合面后的微渗漏情况，并与传统的金刚砂车针技术进行比较。
30颗前磨牙被分为三组：I组——高速手机+37%磷酸；II组——铒激光（350 mJ，4 Hz，112 J/cm²）+37%磷酸；III组——铒激光（350 mJ，4 Hz，112 J/cm²）+铒激光（80 mJ，4 Hz，25 mJ/cm²）。所有窝洞均使用相同的粘结系统，并按照制造商的说明用流动树脂进行修复。牙齿经过热循环处理，然后在完全黑暗的环境中浸泡在50%的硝酸银溶液中8小时。标本沿颊舌方向纵向切成1毫米厚的切片。将每片切片浸入显影液中并拍照，由三名经过校准的检查人员对微渗漏情况进行0至7分的评分。
观察到用铒激光制备并蚀刻的标本与其他组之间存在统计学上的显著差异（P<0.0001）。
可以得出结论，在进行蚀刻时，两种类型的釉质制备之间没有显著差异。仅用铒激光制备和处理釉质表面会导致最高程度的渗漏。
