Mohammadian Fatemeh, Soufi Soroush, Dibaji Fatemeh, Sarraf Pegah, Chiniforush Nasim, Kharrazifard Mohammad Javad
Department of Endodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
Private Practice, Tehran, Iran.
Lasers Med Sci. 2019 Feb;34(1):201-207. doi: 10.1007/s10103-018-02705-0. Epub 2019 Jan 4.
This study aimed to compare the effects of diode and Er:YAG laser irradiation of root dentin on push-out bond strength of mineral trioxide aggregate (MTA) and calcium-enriched mixture (CEM) cements. An in vitro experimental study was conducted on 90 dentin discs, cut out of freshly extracted human teeth. The discs were instrumented to obtain 1.3-mm lumen diameter. Then, they were randomly divided into six groups (n = 15). Groups 1 and 4 subjected to diode laser (Wiser, Doctor Smile, Italy) (980 nm, 1 W, continuous mode) for 10 s and filled with MTA and CEM cements. Groups 2 and 5 subjected to Er:YAG laser (Deka, Italy) (2940 nm, 1 W, 10 Hz, 230 μs) for 10 s and filled with MTA and CEM cements. Groups 3 and 6 (control groups) were filled with MTA and CEM cements without laser irradiation. After 7 days, push-out bond strength test was performed using a universal testing machine in order to evaluate the adhesion of the biomaterials to dentin. The samples were evaluated under a light microscope at × 40 magnification to determine the mode of fracture. Data were analyzed using two-way ANOVA. The highest push-out bond strength (8.76 ± 3.62 MPa) was noted in group 1 (diode/MTA), which was significantly higher than the other groups (P < 0.001). The lowest bond strength (2.61 ± 0.81) was noted in group 6 (control/CEM). Diode laser significantly increased the bond strength of both cements (P < 0.05), but Er:YAG laser irradiation only increased the bond strength of CEM and had no significant effect on MTA (P = 0.603). The bond strength of MTA control group was higher than that of CEM control group (P = 0.001). Push-out bond strength of endodontic cements can be affected by dentin conditioning with diode 980 nm and Er:YAG laser. Nine hundred eighty-nanometer diode laser irradiation is recommended to increase the bond strength of endodontic cements particularly the CEM cement to dentin.
本研究旨在比较二极管激光和铒激光照射牙根牙本质对三氧化矿物凝聚体（MTA）和富钙混合物（CEM）粘结剂推出粘结强度的影响。对从新鲜拔除的人牙切取的90个牙本质圆盘进行了一项体外实验研究。将圆盘制备成内径为1.3毫米的管腔。然后，将它们随机分为六组（n = 15）。第1组和第4组用二极管激光（Wiser，Doctor Smile，意大利）（980纳米，1瓦，连续模式）照射10秒，并用MTA和CEM粘结剂充填。第2组和第5组用铒激光（Deka，意大利）（2940纳米，1瓦，10赫兹，230微秒）照射10秒，并用MTA和CEM粘结剂充填。第3组和第6组（对照组）用MTA和CEM粘结剂充填，不进行激光照射。7天后，使用万能试验机进行推出粘结强度测试，以评估生物材料与牙本质的粘结力。在40倍放大倍数的光学显微镜下对样本进行评估，以确定断裂模式。数据采用双向方差分析进行分析。第1组（二极管/MTA）的推出粘结强度最高（8.76±3.62兆帕），显著高于其他组（P < 0.001）。第6组（对照组/CEM）的粘结强度最低（2.61±0.81）。二极管激光显著提高了两种粘结剂的粘结强度（P < 0.05），但铒激光照射仅提高了CEM的粘结强度，对MTA没有显著影响（P = 0.603）。MTA对照组的粘结强度高于CEM对照组（P = 0.001）。牙髓粘结剂的推出粘结强度可受980纳米二极管激光和铒激光预处理牙本质的影响。建议采用980纳米二极管激光照射以提高牙髓粘结剂尤其是CEM粘结剂与牙本质的粘结强度。
