不同表面处理对氧化锆陶瓷与牙本质粘接强度的影响

目的比较喷砂、激光等不同机械处理对氧化锆陶瓷与牙本质粘接强度的影响。方法制备4 mm×4 mm×6 mm尺寸的长方体瓷块80件,按空白对照及喷砂、Er:YAG激光、Nd:YAG激光、飞秒激光等不同表面处理方式随机分成5组(A~E组,n=16)。使用扫描电镜观察表面形貌,轮廓仪测量粗糙度。用树脂粘接剂将瓷块与制备好的50块牙本质平面粘接,万能实验机测试剪切粘接强度,体式显微镜下分析界面破坏模式,使用SPSS 25.0进行单因素方差分析。结果扫描电镜图像显示,不同处理后的氧化锆表面微观形貌改变显著。粗糙度值从大到小分别为:B组(1.29±0.25)μm,E组(1.05±0.20)μm,C组(0.66±0.11)μm,D组(0.49±0.11)μm,A组(0.34±0.07)μm,B组与E组大于其他任意组别(P<0.05)。剪切强度值从大到小分别为:E组(10.87±2.67)MPa,B组(8.90±1.52)MPa,C组(6.10±1.36)MPa,D组(5.69±1.01)MPa,A组(4.21±0.90)MPa,E组与B组大于其他任意组别(P<0.05),且E组大于B组(P<0.05)。不同表面处理后的粗糙度值与剪切粘接强度值差异均有统计学意义(P<0.05),剪切粘接强度值随着粗糙度值变化而变化,两者变化趋势基本相匹配。结论飞秒激光和喷砂可显著粗化氧化锆表面,使氧化锆陶瓷与树脂粘接剂粘接时形成充分的微机械嵌合作用,可显著提升粘接强度,且飞秒激光提升程度最大,是一种有前景的氧化锆表面处理方法。

Effects of different surface treatments on the bonding strength of zirconia ceramics and dentin

Objective To compare the effects of different mechanical treatments such as sandblasting and laser on the shear bonding strength of zirconia ceramics and dentin.Methods Eighty blocks of zirconia cuboid specimens(4 mm×4 mm×6 mm)were prepared and randomly assigned into 5 groups(n=16)in accordance with their surface treatment:(A)untreated,as control;(B)sandblasted with Al2O3;(C)Er:YAG laser;(D)Nd:YAG laser;(E)femtosecond laser.Scanning electron microscopy was taken to observe surface morphology and profilometer was used to measure roughness.Zirconia blocks were cemented with 50 prepared dentin planes with resin cement.All samples were measured for shear bonding strength with a universal testing machine.Each specimen of interface destruction mode was observed using optical microscope.The data were analyzed by one-way ANOVA using SPSS 25.0 software.Results Scanning electron microscopy images showed that the micromorphology of the zirconia surface after different treatments changed significantly.The values of roughness from large to small were:Group B(1.29±0.25)μm,Group E(1.05±0.20)μm,Group C(0.66±0.11)μm,Group D(0.49±0.11)μm,Group A(0.34±0.07)μm.Groups B and E were larger than any other group(P<0.05).The shear bond strength values from large to small were:Group E(10.87±2.67)MPa,Group B(8.90±1.52)MPa,Group C(6.10±1.36)MPa,Group D(5.69±1.01)MPa,Group A(4.21±0.90)MPa.Groups E and B were larger than any other group(P<0.05),and Group E was larger than Group B(P<0.05).The differences in the values of roughness and shear bond strength were both statistically significant after surface treatments(P<0.05),the values of shear bond strength varied with the roughness and the variation tendency of the two were generally consistent.Conclusion Femtosecond laser and sandblasting can significantly roughen the surface of zirconia.So sufficient micromechanical interlocking effect is formed when zirconia ceramics and resin adhesive are bonded,which significantly improves the bonding strength.And femtosecond laser is the most ideal way to improve the shear bonding strength,which is a promising surface treatment for zirconia ceramic.