Effectiveness of cold atmospheric plasma in decontaminating enterococcus faecalis colonized collagen and PTFE membranes used in guided bone regeneration: a comparative in vitro investigation.

Purpose: Wound healing disorders caused by bacterial infections in dental surgery, especially where membranes are used, are a common issue in oral surgery. Cold atmospheric plasma (CAP) offers a non-invasive solution for surface decontamination, including dental implants. The aim of this study was to evaluate the antibacterial effectiveness of CAP on various clinically applied membranes made of collagen and polytetrafluoroethylene (PTFE).

Materials and methods: To assess the antibacterial properties of CAP, enterococcus faecalis were seeded on different membranes: Memlock (collagen), Memlock Pliable (collagen), Agronaut (collagen), and PermaPro (PTFE); n = 4. After in vitro cultivation for 6 days, CAP using a kINPen^® MED with an output of 5 W was applied 5 min and 10 min. Bacterial colony-forming units (CFU) were quantified to detect decontamination effectiveness. In addition, live and dead staining as well as scanning electron microscopy (SEM) of membranes was performed for validation and surface texture analysis.

Results: Bacterial colonization was highest on collagen-based membranes (CFU Memlock: 14.38 ± 8.91). The results showed that CAP significantly reduced bacterial colonization on all membrane types after 10 min application of CAP; Memlock (CFU after 10 min 0.22 ± 0.16^10⁶; p = 0.0256), Argonaut (CFU after 10 min 0.02 ± 0.01^10⁶; p = 0.0129) and PermaPro (complete bacterial decontamination; p = 0.0058). This was paralleled by fluorescence and scanning electron microscopy. CAP was most effective on smooth membrane surfaces as SEM revealed.

Conclusion: CAP thus offers a non-invasive, cost-effective method to reduce bacterial infections in guided bone regeneration using membranes.