Effects of Non-Thermal Atmospheric Pressure Plasma and Sodium Hypochlorite Solution onEnterococcus faecalisBiofilm: An Investigation in Extracted Teeth

Abstract

The aim of this study was to compare the effect of atmospheric pressure plasma (APP) with sodium hypochlorite (NaOCl) or the combination of APP and NaOCl on Enterococcus faecalis biofilm in root canals of extracted human teeth. The disinfection efficiency was determined as the logarithm of the number of colony‐forming units (CFU). Additionally, scanning electron microscopy (SEM) was used to visualize the treatment effect on biofilm. The adjunctive treatment with Plasma + O2 has a small additive, albeit statistically not significant effect in the CFU reduction of an E. faecalis biofilm compared to the 12 min monotherapy with NaOCl. The effectiveness of Plasma + O2 could be significantly increased by longer treatment time.

Effects of cold atmospheric pressure plasma and disinfecting agents on Candida albicans in root canals of extracted human teeth

“…SEM showed no colonization in the dentinal tubules after using plasma/O 2 . Similar effects were shown by others and our working group [18,19]. Unlike our CFU analysis, scanning electron micrographs indicate an additive effect of the combined therapies.…”

“…Antifungal activity of plasma/O 2 was time‐dependent. Earlier studies could demonstrate similar observations [19, 26]. Previous studies indicated oxidation processes caused by reactive oxygen species to be responsible for the disinfecting effect of plasma [14].…”

“…In former experiments on dental biofilms grown on titanium discs Koban et al observed a significant additive effect when applying combined treatments [21]. In contrast, Hüfner et al as well as this study did not show any beneficial effect of combined treatments [19]. Both latter studies used natural teeth with the disinfectant forming a liquid column in the tooth whereas on titanium discs the fluid formed a thin film.…”

“…Duske et al compared the disinfection capacity of different plasma sources on Staphylococcus epidermidis biofilms grown on cover slips, demonstrating a higher reduction rate using the kINPen08 compared to the kINPen09 or kINPenMED, which is one reason why our group favored the kINPen08 in this study [27]. Another reason is that we wanted to ensure comparability with our previous studies with the kINPen08 in the area of endodontics [17, 19]. The main difference between kINPen09, kINPenMED and kINPen08 is the higher power of the kINPen08 [27].…”

Antibacterial efficacy of cold atmospheric plasma against Enterococcus faecalis planktonic cultures and biofilms in vitro

“…CAPs are known to effectively inactivate bacteria and fungi (independent of their resistance profiles towards conventional antimicrobials as well as on different surfaces and in biofilms), spores and viruses [17, 18]. Furthermore, it could be shown that CAP doses can be found where pathogens can be inactivated without mammalian tissues being harmed or without changing the characteristics of the respective materials that bacteria are attached to [19, 20]. Due to these results and, moreover, as CAP operate at low temperatures (5–10°C above room temperature only), various applications in hygiene ( e .…”