Dal Piva Amo, Contreras Lpc, Ribeiro F C, Anami L C, Camargo Sea, Jorge Aoc, Bottino M A
Oper Dent. 2018 May/Jun;43(3):315-325. doi: 10.2341/17-011-L. Epub 2018 Mar 13.
This study evaluated the morphology, biofilm formation, and viability of human gingival fibroblasts in contact with two monolithic ceramics after two different finishing techniques: polishing or glazing. For this, 92 blocks (4.5 × 4.5 × 1.5 mm) of each ceramic were made using high translucency zirconia partially stabilized by yttrium (YZHT) and lithium silicate reinforced by zirconium (ZLS).
Blocks were sintered and then divided into glazing (g) or polishing (p) surface finish. Surface roughness (Ra and RSm) was evaluated through a contact rugosimeter and profilometry. Specimens were contaminated for heterotypic biofilm formation with Streptococcus mutans, Streptococcus sanguinis and Candida albicans for 16 hours. Biofilm was quantified by counting the colony forming units (CFU/mL) and analyzed by scanning electron microscopy (SEM). Fibroblast viability was evaluated by MTT assay. Surface free energy (SFE) was also determined. Roughness data were evaluated using nonparametric tests, while SFE, MTT and CFU results were evaluated by analysis of variance and Tukey test, and MTT data were also submitted to t-test (all, α=0.05).
Results showed that polished samples presented a lower high profile mean ( p<0.001); however, YZHTg presented less space between defects ( p=0.0002). SFE showed that YZHT presented higher SFE than ZLS. Profilometry evidenced more homogeneity on polished surfaces. The interaction of finishing technique and microorganisms influenced the CFU ( p=0.00). MTT assay demonstrated initial severe cytotoxic behavior for polished surfaces. SEM images showed homogeneous surfaces, except for glazed YZHT.
Glazed surfaces have a greater roughness and tend to accumulate more biofilm. Polished surfaces have higher SFE; however, they are temporarily cytotoxic.
本研究评估了在两种不同的表面处理技术（抛光或上釉）后，与两种整体陶瓷接触的人牙龈成纤维细胞的形态、生物膜形成和活力。为此，使用钇部分稳定的高透明度氧化锆（YZHT）和锆增强的硅酸锂（ZLS）制作了每种陶瓷的92个块体（4.5×4.5×1.5毫米）。
将块体烧结，然后分为上釉（g）或抛光（p）表面处理。通过接触式粗糙度仪和轮廓仪评估表面粗糙度（Ra和RSm）。用变形链球菌、血链球菌和白色念珠菌对标本进行异型生物膜形成污染16小时。通过计数菌落形成单位（CFU/mL）对生物膜进行定量，并通过扫描电子显微镜（SEM）进行分析。通过MTT法评估成纤维细胞活力。还测定了表面自由能（SFE）。使用非参数检验评估粗糙度数据，而SFE、MTT和CFU结果通过方差分析和Tukey检验进行评估，MTT数据也进行t检验（所有检验，α = 0.05）。
结果表明，抛光样品的高轮廓平均值较低（p < 0.001）；然而，YZHTg在缺陷之间的间隙较小（p = 0.0002）。SFE表明，YZHT的SFE高于ZLS。轮廓仪证明抛光表面更均匀。表面处理技术和微生物的相互作用影响了CFU（p = 0.00）。MTT分析表明，抛光表面最初具有严重的细胞毒性行为。SEM图像显示，除了上釉的YZHT外，表面均匀。
上釉表面粗糙度更大，倾向于积累更多生物膜。抛光表面具有更高的SFE；然而，它们具有暂时的细胞毒性。
