Silva Fernanda P, Vilela Ana L R, Almeida Matheus M G, Oliveira André R F, Raposo Luís H A, Menezes Murilo S
Department of Operative Dentistry and Dental Materials, School of Dentistry, UFU - Universidade Federal de Uberlândia, Uberlândia, MG, Brazil.
Department of Dentistry, School of Dentistry, UniRV- University of Rio Verde, Rio Verde, GO, Brazil.
Braz Dent J. 2019 Mar-Apr;30(2):164-170. doi: 10.1590/0103-6440201902101. Epub 2019 Apr 4.
This study evaluated the effect of different finishing-polishing protocols on surface roughness, gloss, morphology and biaxial flexural strength of pressable fluorapatite glass ceramic. Thirty ceramic discs (12x1 mm) were produced and divided into five groups (n=6): CT: control (glaze); DA: fine grit diamond bur; DG: DA + new glaze layer; DP: DA + felt disk with fine grit diamond paste; DK: DA+ sequential polishing with silicon abrasive instruments, goat hair brush and cotton wheel. The specimens were analyzed for surface roughness (Ra) under profilometry and atomic force microscopy (AFM). Gloss was measured with spectrophotometry and micromorphology with scanning electron microscopy (SEM). Flexural strength was assessed by biaxial flexural strength test. Data were analyzed using one-way ANOVA and Tukey's post hoc test (a=0.05). DK showed the lowest surface roughness values and DA presented the highest in the perfilometer analysis. No significant differences were observed in the AFM for the CT, DG and DK groups, which presented the lower surface roughness; DA and DP had the higher Ra values. The DA, DP and CT showed the lowest surface gloss values, and the reflectance was significantly different from those observed for DK and DG groups. SEM analysis revealed the smoothest surface for DK group, followed by DG and CT groups; DA and DP groups exhibited variable degrees of surface irregularities. No significant differences were observed among groups for the biaxial flexural strength. The polishing protocol used in DK group can be a good alternative for chairside finishing of adjusted pressable fluorapatite glass ceramic surfaces.
本研究评估了不同的精修 - 抛光方案对可压制成型氟磷灰石玻璃陶瓷的表面粗糙度、光泽度、形态和双轴弯曲强度的影响。制备了30个陶瓷圆盘（12×1毫米）并分为五组（n = 6）：CT：对照组（釉面）；DA：细粒度金刚石车针；DG：DA + 新的釉面层；DP：DA + 带有细粒度金刚石膏的毡盘；DK：DA + 依次用硅磨料工具、山羊毛刷和棉轮进行抛光。通过轮廓仪和原子力显微镜（AFM）分析样品的表面粗糙度（Ra）。用分光光度法测量光泽度，用扫描电子显微镜（SEM）观察微观形态。通过双轴弯曲强度试验评估弯曲强度。使用单因素方差分析和Tukey事后检验（α = 0.05）分析数据。在轮廓仪分析中，DK组的表面粗糙度值最低，DA组的最高。在AFM分析中，CT、DG和DK组未观察到显著差异，这三组的表面粗糙度较低；DA和DP组的Ra值较高。DA、DP和CT组的表面光泽度值最低，其反射率与DK和DG组观察到的显著不同。SEM分析显示DK组的表面最光滑，但DG和CT组次之；DA和DP组表现出不同程度的表面不规则性。在双轴弯曲强度方面，各组之间未观察到显著差异。DK组中使用的抛光方案可以作为椅旁精修调整后的可压制成型氟磷灰石玻璃陶瓷表面的良好选择。
