Department of Conservative Dentistry, Center for Dentistry and Oral Hygiene, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
Conservative Dentistry Department, School of Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
Int Endod J. 2019 Dec;52(12):1773-1788. doi: 10.1111/iej.13198. Epub 2019 Aug 31.
To investigate the anti-biofilm efficacy and working mechanism of several NaOCl concentrations on dual-species biofilms of different architecture as well as the changes induced on the architecture of the remaining biofilms.
Streptococcus oralis J22 and Actinomyces naeslundii T14V-J1 were co-cultured under different growth conditions on saliva-coated hydroxyapatite discs. A constant-depth film fermenter (CDFF) was used to grow steady-state, four-day mature biofilms (dense architecture). Biofilms were grown under static conditions for 4 days within a confined space (less dense architecture). Twenty microlitres of buffer, 2-, 5-, and 10% NaOCl were applied statically on the biofilms for 60 s. Biofilm disruption and dissolution, as well as bubble formation, were evaluated with optical coherence tomography (OCT). The viscoelastic profile of the biofilms post-treatment was assessed with low load compression testing (LLCT). The bacteria/extracellular polysaccharide (EPS) content of the biofilms was examined through confocal laser scanning microscopy (CLSM). OCT, LLCT and CLSM data were analysed through one-way analysis of variance (ANOVA) and Tukey's HSD post-hoc test. Linear regression analysis was performed to test the correlation between bubble formation and NaOCl concentration. The level of significance was set at a < 0.05.
The experimental hypothesis according to which enhanced biofilm disruption, dissolution and bubble formation were anticipated with increasing NaOCl concentration was generally confirmed in both biofilm types. Distinct differences between the two biofilm types were noted with regard to NaOCl anti-biofilm efficiency as well as the effect that the several NaOCl concentrations had on the viscoelasticity profile and the bacteria/EPS content. Along with the bubble generation patterns observed, these led to the formulation of a concentration and biofilm structure-dependent theory of biofilm removal.
Biofilm architecture seems to be an additional determining factor of the penetration capacity of NaOCl, and consequently of its anti-biofilm efficiency.
研究不同浓度次氯酸钠对不同结构双物种生物膜的抗生物膜效能和作用机制，以及对剩余生物膜结构的影响。
将口腔链球菌 J22 和内氏放线菌 T14V-J1 在不同生长条件下共同培养在唾液包被的羟磷灰石片上。使用恒深膜发酵器（CDFF）在受限空间内静态培养 4 天成熟的生物膜（致密结构）。在静态条件下培养 4 天形成生物膜（疏松结构）。将 20 微升缓冲液、2%、5%和 10%次氯酸钠分别施加于生物膜上 60 秒。采用光学相干断层扫描（OCT）评估生物膜的破坏和溶解以及气泡的形成。用低负荷压缩试验（LLCT）评估处理后生物膜的粘弹性特征。采用共聚焦激光扫描显微镜（CLSM）检测生物膜中的细菌/胞外多糖（EPS）含量。通过单向方差分析（ANOVA）和 Tukey 的 HSD 事后检验分析 OCT、LLCT 和 CLSM 数据。进行线性回归分析以检验气泡形成与次氯酸钠浓度之间的相关性。显著性水平设为 a < 0.05。
根据实验假设，随着次氯酸钠浓度的增加，预计会增强生物膜的破坏、溶解和气泡形成，这一假设在两种生物膜类型中都得到了验证。两种生物膜类型之间在次氯酸钠抗生物膜效率以及几种次氯酸钠浓度对粘弹性特征和细菌/EPS 含量的影响方面存在明显差异。这些差异与观察到的气泡生成模式相结合，形成了一种基于浓度和生物膜结构的生物膜去除理论。
生物膜结构似乎是次氯酸钠穿透能力的另一个决定因素，进而影响其抗生物膜效率。
Zotero 插件
