Division of Endodontics, Department of Restorative Dental Science, College of Dentistry, King Saud University, Riyadh, Saudi Arabia.
Division of Endodontics, Department of Restorative Dental Science, College of Dentistry, King Saud University, Riyadh, Saudi Arabia.
J Endod. 2020 Nov;46(11):1689-1694. doi: 10.1016/j.joen.2020.07.001. Epub 2020 Jul 15.
The aim of this study was to evaluate the antibiofilm effectiveness of calcium hydroxide (Ca[OH]) mixed with 0.02% silver nanoparticles (AgNPs) in comparison with 1 mg/mL triple antibiotic paste (TAP), Ca(OH), and 0.02% AgNPs against Enterococcus faecalis using confocal laser scanning microscopy.
Ninety dentin disks were prepared, sterilized, and inoculated with E. faecalis to establish a 3-week-old biofilm model. The samples received 1 mg/mL TAP, a mixture of Ca(OH) + 0.02% AgNPs, Ca(OH), or 0.02% AgNPs (n = 20/group). Specimens in each group were equally subdivided into 2 groups and incubated for 2 and 4 weeks. Untreated dentin disks (n = 10) were exposed to sterile saline solution and acted as a positive control. Sterile dentin disks (n = 10) were incubated anaerobically in brain-heart infusion broth and served as a negative control. At the end of each observation period, the specimens were stained with LIVE/DEAD BacLight dye (Molecular Probes, Eugene, OR) and analyzed with confocal laser scanning microscopy to determine the proportion of dead cells in the biofilm. Statistical analysis was performed using the generalized linear model repeated measure and Tukey tests (P < .05).
A significantly greater proportion of dead cells was observed in the samples treated with 1 mg/mL TAP (90.39% and 99.41%) and a mixture of Ca(OH) + AgNPs (90.85% and 98.49%) than those in the samples treated with Ca(OH) (76.14% and 91.71%) and AgNPs (62.83% and 88.07%) at 2 and 4 weeks, respectively. A significant difference in the antibiofilm effectiveness was observed among the groups (P < .05), except for 1 mg/mL TAP and the mixture of Ca(OH) + AgNPs (P > .05). All medicaments showed a significant difference in antibiofilm efficacy at the 2 time points.
The mixture of Ca(OH) + AgNPs showed a high antibiofilm effect and was not significantly different from 1 mg/mL TAP. Furthermore, long-term contact between intracanal medicaments and bacterial cells achieved significant antibiofilm efficacy.
本研究旨在通过共聚焦激光扫描显微镜评估氢氧化钙（Ca[OH]）与 0.02%载银纳米粒子（AgNPs）混合物与 1mg/ml 三联抗生素糊剂（TAP）、Ca（OH）和 0.02%AgNPs 对粪肠球菌的抗生物膜效果。
制备 90 个牙本质圆盘，经消毒后接种粪肠球菌，建立 3 周龄生物膜模型。样品分别接受 1mg/ml TAP、Ca（OH）+0.02%AgNPs 混合物、Ca（OH）或 0.02%AgNPs（n=20/组）。每组标本等分为 2 组，分别孵育 2 周和 4 周。未经处理的牙本质圆盘（n=10）暴露于无菌生理盐水溶液中作为阳性对照。无菌牙本质圆盘（n=10）在脑心浸液肉汤中厌氧孵育作为阴性对照。在每个观察期结束时，用 LIVE/DEAD BacLight 染料（Molecular Probes，Eugene，OR）对标本进行染色，并用共聚焦激光扫描显微镜分析以确定生物膜中死亡细胞的比例。采用广义线性模型重复测量和 Tukey 检验进行统计学分析（P<0.05）。
在接受 1mg/ml TAP（90.39%和 99.41%）和 Ca（OH）+AgNPs 混合物（90.85%和 98.49%）治疗的样本中，死亡细胞的比例明显高于接受 Ca（OH）（76.14%和 91.71%）和 AgNPs（62.83%和 88.07%）治疗的样本，分别为 2 周和 4 周。各组间的抗生物膜效果差异有统计学意义（P<0.05），除 1mg/ml TAP 和 Ca（OH）+AgNPs 混合物（P>0.05）外。所有药物在 2 个时间点的抗生物膜效果均有显著差异。
Ca（OH）+AgNPs 混合物具有较高的抗生物膜效果，与 1mg/ml TAP 无显著差异。此外，根管内药物与细菌细胞的长期接触可达到显著的抗生物膜效果。
