Killing activity of nonequilibrium plasma against young and old Enterococcus faecalis biofilms with long-term exposure in infected root canals in vitro
10.3760/cma.j.issn.1002-0098.2018.10.007
- VernacularTitle: 非平衡等离子体对感染根管粪肠球菌生物膜影响的实验研究
- Author:
Tianfeng DU
1
;
Xuezhi TANG
2
;
Qi SHI
2
;
Kang GAN
1
;
Juanfang ZHU
1
;
Yingguang CAO
2
Author Information
1. Department of Stomatology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
2. Department of Stomatology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
- Publication Type:Journal Article
- Keywords:
Biofilms;
Enterococcus faecalis;
Chlohexidine;
Root canal disinfection;
Nonequlibrium plasma
- From:Chinese Journal of Stomatology
2018;53(10):681-687
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To evaluate the antimicrobial activity of nonequilibrium plasma against Enterococcus faecalis (Ef) biofilms in vitro and to obtain novel evidence of root canal disinfection with nonequilibrium plasma.
Methods:Sterile cover slips and single-rooted canals were filled with Ef and incubated to form 1-week-old and 3-week-old biofilms, respectively. The infected samples were subjected to nonequilibrium plasma, 2% chlorhexidine digluconate (CHX) and saline for 3, 10 and 30 minutes, respectively. After treatment, the killing effectiveness of nonequilibrium plasma was analyzed by using laser scanning confocal microscopy (LSCM) and colony forming unit (CFU) counting.
Results:The 3-dimentional reconstruction LSCM images showed that about 48.3%-79.8% of 1-week-old Ef biofilm cells and 40.0%-67.4% of 3-week-old biofilm cells were killed by nonequilibrium plasma and 2% CHX compared to saline (P<0.05). The proportion of killing activity was lower after 3 minutes (40.0%-50.9% killing) than after 10 minutes (65.3%-77.8% killing) and 30 minutes (66.4%-79.8% killing) (P<0.05). And the killing of biofilm bacteria was fastest during the first 3 minutes (13.3%-17.0% killing per minute) and slow down greatly after 10 minutes. Remarkably more bacteria were killed in 1-week-old Ef biofilms (48.3%-79.8% killing) than in 3-week-old biofilms (P<0.05).
Conclusions:The nonequilibrium plasma killed more Ef biofilm cells in infected root canals showed promotional as an additional approach against bacterial biofilms during root canal disinfection.
