OBJECTIVE To evaluate the addition of dimethylaminohexadecyl methacrylate (DMAHDM) and chlorhexidine diacetate on cytotoxicity, antimicrobial activity, physical, and mechanical properties of a self-cured resin. METHODS 132 disk-shaped and 48 rectangular specimens were divided into four experimental groups as described: Control Group (CG - no addition), dCHX (1%), DMAHDM (5%), and DMAHDM+dCHX (5%+1%). The biofilm viability, flexural strength (FS - ISO 20795-1:2013), surface roughness (SR), and color stability (ΔE) were analyzed after being stored for 4 weeks in distilled water and immersed for 72h in coffee. Cytotoxicity was measured after 24h, 3, and 7 days of elution using an MTT test on L929 cells (ISO 10993-5:2009). SR and ΔE were measured by a contact profilometer and a spectrophotometer using the CIELab parameter. Data were submitted to ANOVA and Bonferroni's/Tukey's tests (p≤0.05). RESULTS Significant antimicrobial activity against Streptococcus mutans and Candida albicans was detected in all groups when compared to the CG (p<0.05). Only the dCHX group, in 24h of elution, demonstrated no cytotoxicity effects. There was a statistical difference for FS on the tested groups (p<0.05). No differences were detected in the initial roughness' measurements among the groups (p>0.05). However, after storage and immersion in coffee, the groups containing DMAHDM presented with rougher surfaces and significantly lower color stability compared to the control (p<0.05). SIGNIFICANCE The addition of dCHX and DMAHDM in self-cured resin presented antimicrobial properties; however, cytotoxicity, physical, and mechanical properties were compromised.

中文翻译：

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由甲基丙烯酸季铵盐和洗必泰改性的自固化树脂：细胞毒性，抗微生物，物理和机械性能。

目的评估甲基丙烯酸二甲基氨基十六烷基酯（DMAHDM）和双乙酸洗必泰对自固化树脂的细胞毒性，抗菌活性，物理和机械性能的影响。方法将132个盘状和48个矩形标本按所述分为四个实验组：对照组（CG-不添加），dCHX（1％），DMAHDM（5％）和DMAHDM + dCHX（5％+ 1％） 。在蒸馏水中储存4周并在咖啡中浸泡72小时后，分析了生物膜的生存力，弯曲强度（FS-ISO 20795-1：2013），表面粗糙度（SR）和颜色稳定性（ΔE）。使用L929细胞（ISO 10993-5：2009）的MTT测试，在洗脱24小时，3天和7天后测量细胞毒性。SR和ΔE使用CIELab参数通过接触轮廓仪和分光光度计测量。将数据提交给方差分析和Bonferroni / Tukey检验（p≤0.05）。结果与CG相比，所有组均检测到对变形链球菌和白色念珠菌的显着抗菌活性（p <0.05）。在洗脱的24小时内，只有dCHX组没有细胞毒性作用。在测试组中，FS有统计学差异（p <0.05）。各组之间的初始粗糙度测量值均未发现差异（p> 0.05）。但是，在储存和浸入咖啡中后，与对照组相比，含DMAHDM的组的表面更粗糙，颜色稳定性也显着降低（p <0.05）。重要性在自固化树脂中添加dCHX和DMAHDM表现出抗菌性能。然而，细胞毒性，物理和机械性能受到损害。