Kirmali Omer, Akin Hakan, Ozdemir Ali Kemal
Department of Prosthodontics, Faculty of Dentistry, Akdeniz University, Antalya, Turkey.
Photomed Laser Surg. 2013 Jun;31(6):261-8. doi: 10.1089/pho.2013.3487.
The aim of this study was to evaluate the effect of different surface treatments: sandblasting, liners, and different laser irradiations on shear bond strength (SBS) of pre-sintered zirconia to veneer ceramic.
The SBS between veneering porcelain and zirconium oxide (ZrO2) substructure was weak. Various surface treatment methods have been suggested for zirconia to obtain high bond strength to veneering porcelain. There is no study that evaluated the bond strength between veneering porcelain and the different surface treatments on pre-sintered ZrO2 substructure.
Two hundred specimens with 7 mm diameter and 3 mm height pre-sintered zirconia blocks were fabricated. Specimens were randomly divided into 10 groups (n=20) according to surface treatments applied. Group C, untreated (Control); Group E, erbium:yttrium-aluminum-garnet (Er:YAG) laser irradiated; Group N, neodymium:yttrium-aluminum-garnet (Nd:YAG) laser irradiated; Group SB, sandblasted; Group L, liner applied; Group NL, Nd:YAG laser irradiated+liner applied; Group EL, Er:YAG laser irradiated+liner applied; Group SN, sandblasted+Nd:YAG laser irradiated; Group SE, sandblasted+Er:YAG laser irradiated; and Group SL, sandblasted+liner applied. The disks were then veneered with veneering porcelain. Before the experiment, specimens were steeped in 37°C distilled water for 24 h. All specimens were thermocycled for 5000 cycles between 5°C and 55°C with a 30 sec dwell time. Shear bond strength test was performed at a crosshead speed of 1 mm/min. The fractured specimens were examined under a stereomicroscope to evaluate the fracture pattern.
Surface treatments significantly changing the topography of the yttrium-stabilized tetragonal zirconia (Y-TZP) ceramic according to scanning electron microscopic (SEM) images. The highest mean bond strength value was obtained in Group SE, and the lowest bond strength value was observed in NL group. Bond strength values of the other groups were similar to each other.
This study shows that sandblasting+Er:YAG, sandblasting, Er:YAG+liner, sandblasting+Nd:YAG, and Er:YAG laser treatment on pre-sintered ZrO2 substructure increased the bond strength to veneering porcelain, compared with other surface treatments. After different surface treatments, there was no difference in surface roughness of pre-sintered zirconia to compare after sintering; sintering enhanced the bond strength within the limitations of present study.
本研究旨在评估不同表面处理方法（喷砂、使用衬层以及不同的激光照射）对预烧结氧化锆与饰面陶瓷之间剪切粘结强度（SBS）的影响。
饰面瓷与氧化锆（ZrO₂）底层结构之间的SBS较弱。已提出多种用于氧化锆的表面处理方法，以获得与饰面瓷的高粘结强度。尚无研究评估饰面瓷与预烧结ZrO₂底层结构上不同表面处理之间的粘结强度。
制作了200个直径7mm、高3mm的预烧结氧化锆块标本。根据所应用的表面处理方法，将标本随机分为10组（n = 20）。C组，未处理（对照组）；E组，铒钇铝石榴石（Er:YAG）激光照射；N组，钕钇铝石榴石（Nd:YAG）激光照射；SB组，喷砂处理；L组，使用衬层；NL组，Nd:YAG激光照射 + 使用衬层；EL组，Er:YAG激光照射 + 使用衬层；SN组，喷砂 + Nd:YAG激光照射；SE组，喷砂 + Er:YAG激光照射；SL组，喷砂 + 使用衬层。然后用饰面瓷对圆盘进行饰面处理。实验前，将标本在37°C蒸馏水中浸泡24小时。所有标本在5°C至55°C之间进行5000次热循环，保压时间为30秒。以1mm/min的十字头速度进行剪切粘结强度测试。在立体显微镜下检查断裂的标本，以评估断裂模式。
根据扫描电子显微镜（SEM）图像，表面处理显著改变了钇稳定四方氧化锆（Y-TZP）陶瓷的形貌。SE组获得了最高的平均粘结强度值，NL组观察到最低的粘结强度值。其他组别的粘结强度值彼此相似。
本研究表明，与其他表面处理相比，对预烧结ZrO₂底层结构进行喷砂 + Er:YAG、喷砂、Er:YAG + 衬层、喷砂 + Nd:YAG以及Er:YAG激光处理可提高与饰面瓷的粘结强度。经过不同表面处理后，预烧结氧化锆烧结后的表面粗糙度没有差异可供比较；在本研究的范围内，烧结增强了粘结强度。
