Department of General Dentistry, Peking University School and Hospital of Stomatology, National Center of Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, 100081, China.
Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, 100871, China.
BMC Oral Health. 2023 Mar 8;23(1):133. doi: 10.1186/s12903-023-02813-6.
Enterococcus faecalis (E. faecalis) is the most frequently isolated bacteria from teeth with root canal treatment failure. This study aims to evaluate the disinfection effect of ultrasonic-mediated cold plasma-loaded microbubbles (PMBs) on 7d E. faecalis biofilm, the mechanical safety and the mechanisms.
The PMBs were fabricated by a modified emulsification process and the key reactive species, nitric oxide (NO) and hydrogen peroxide (HO) were evaluated. The 7d E. faecalis biofilm on human tooth disk was constructed and divided into the following groups: PBS, 2.5%NaOCl, 2%CHX, and different concentrations of PMBs (10 mL, 10 mL). The disinfection effects and elimination effects were verified with confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Microhardness and roughness change of dentin after PMBs treatment were verified respectively.
The concentration of NO and HO in PMBs increased by 39.99% and 50.97% after ultrasound treatment (p < 0.05) respectively. The CLSM and SEM results indicate that PMBs with ultrasound treatment could remove the bacteria and biofilm components effectively, especially those living in dentin tubules. The 2.5% NaOCl presented an excellent effect against biofilm on dishes, but the elimination effect on dentin tubules is limited. The 2% CHX group exhibits significant disinfection effect. The biosafety tests indicated that there is no significant changes on microhardness and roughness after PMBs with ultrasound treatment (p > 0.05).
PMBs combined with ultrasound treatment exhibited significant disinfection effect and biofilm removal effect, the mechanical safety is acceptable.
粪肠球菌（E. faecalis）是根管治疗失败牙齿中最常分离出的细菌。本研究旨在评估超声介导载冷等离子体微泡（PMBs）对 7d 粪肠球菌生物膜的消毒效果、机械安全性及其机制。
通过改良乳化工艺制备 PMBs，并评估关键活性物质一氧化氮（NO）和过氧化氢（HO）。构建人牙盘上 7d 粪肠球菌生物膜，分为 PBS、2.5%NaOCl、2%CHX 和不同浓度的 PMBs（10 mL、10 mL）。通过共聚焦激光扫描显微镜（CLSM）和扫描电子显微镜（SEM）验证消毒效果和消除效果。分别验证 PMBs 处理后牙本质的显微硬度和粗糙度变化。
超声处理后 PMBs 中 NO 和 HO 的浓度分别增加了 39.99%和 50.97%（p<0.05）。CLSM 和 SEM 结果表明，超声处理后的 PMBs 能有效去除细菌和生物膜成分，特别是位于牙本质小管内的细菌和生物膜成分。2.5%NaOCl 对平板上的生物膜具有优异的效果，但对牙本质小管内的消除效果有限。2%CHX 组具有显著的消毒效果。生物安全测试表明，超声处理后的 PMBs 对微硬度和粗糙度没有显著影响（p>0.05）。
PMBs 联合超声处理具有显著的消毒效果和生物膜去除效果，机械安全性可接受。
