The Decontamination Effect of an Oscillating Chitosan Brush Compared With an Ultrasonic PEEK-Tip: An In Vitro Study Using a Dynamic Biofilm Model.

Objectives: This study aimed to assess the effect of an oscillating chitosan brush (OCB) compared with an ultrasonic device with PEEK tip (US-PEEK) for mechanical implant surface decontamination using an in vitro model combining 3D models and a validated dynamic multispecies biofilm.

Materials And Methods: A multispecies biofilm using six bacterial strains (Streptococcus oralis, Veillonella parvula, Actinomyces naeslundii, Fusobacterium nucleatum, Porphyromonas gingivalis, and Aggregatibacter actinomycetemcomitans) was seeded on dental implants with machined and sandblasted, large-grit and acid-etched (SLA) surfaces. These were installed in 3D models depicting peri-implant defect. Mechanical decontamination was performed for 120 s using either an OCB or a US-PEEK. A negative control group received no treatment. Scanning electron microscopy (SEM) was used to evaluate the bacterial composition and quantitative PCR (qPCR) analyzed the number of each bacterial species [colony-forming units per milliliter (CFU/mL)].

Results: Well-structured biofilms with a dense microbial distribution were observed on the negative control implants after 72 h. qPCR following mechanical decontamination showed a scarce bacterial reduction in the OCB group. The US-PEEK group exhibited a significant decrease in bacterial species compared to both OCB and control groups (p < 0.05). A biofilm removal effect was also observed in the OCB group for the machined implant surfaces.

Conclusion: In vitro assessment using an anatomical 3D model showed that mechanical decontamination effectively reduced biofilm. The US-PEEK group demonstrated biofilm reduction on the SLA surface, while the OCB group showed a reduction on the machined implant surface. Additionally, the US-PEEK group demonstrated greater efficacy in reducing bacterial numbers.