不同抛光时长对氧化锆表面粗糙度和表面晶相的影响

The effect of different polishing times on the surface roughness and phase transformation of zirconia

目的:比较不同抛光时长对氧化锆表面粗糙度和晶相结构的影响。方法:氧化锆锆盘切割烧结制作锆片试件30个,烧结试件后表面使用500目砂纸进行同质性处理后在水冷状态下使用金刚砂车针进行表面调磨20 s,模拟临床调牙合过程,分为调磨未抛光组(GR组),调磨后上釉组(GL组),调磨后使用TOB套装抛光,每步骤抛光时长20 s(T20组),40 s(T40组)和60 s(T60组)。试件表面粗糙度使用轮廓仪评估,并进行扫描电镜观察及XRD分析。结果:GR组粗糙度最大,T20组次之,T40和T60组无统计学差异,其粗糙度较T20小,但均大于GL组。GR组试件表面粗糙,形态不规则,缺陷最多;GL组试件表面光滑,形态规则,缺陷最少。T20组,T40组,T60组表面形貌逐渐光滑,形态逐渐规则,缺陷变少。与XRD测量结果基准G相比,GR组及不同时长抛光过程未导致氧化锆试样发生相变。结论:上釉可获得最小的表面粗糙度。TOB氧化锆抛光套装三步法抛光,每步骤抛光时长60 s可达最佳的抛光效果,粗糙度最低,但高于上釉;每步抛光时长20 s, 40 s, 60 s对其表面晶相无影响。

Objective:To compare the effect of different polishing times on the surface roughness and phase transformation of zirconia.Methods:The ST zirconium plate was cut into 30 zirconium pieces, after sintering final polishing was performed using 500 grit abrasive papers for standardization of the surface roughness.Specimens were simulated by surface grinding for 20 s in the water cooled and further grouped in 5 group, unpolished group(GR group),glaze group after grinding(GL group)and polished using TOB kit after grinding, with polishing duration of 20 s(T20 group),40 s(T40 group)and 60 s(T60 group)per step.After polishing, roughness was determined on an optical profilometer.One specimen from each subgroup was visualized by scanning electron microscopy and XRD analysis.Results:The largest roughness of the GR group, second to T20,T40 and T60,and the roughness was smaller than T20,but all greater than GL.SEM analysis showed that the GR specimens have rough surface, irregular morphology and the most defects.GL have smooth surface, regular morphology and the least defects.T20 group, T40 group and T60 group showed gradually smooth surface morphology, gradually regular morphology, and fewer defects.In contrast to the XRD measurements of the sintering test benchmark G,the grinding group GR group and the long polishing process did not cause a phase change in the zirconia samples.Conclusion:Glazing results in minimal surface roughness.When polishing the zirconia by using the TOB zirconia polishing kit, each step of polishing for 60 s can achieve the best polishing effect, with the lowest roughness but higher than the glaze.TOB polishing kit has no effect on the surface phase transformation when the polishing duration of each step is 20 s, 40 s and 60 s.