Antibiofilm efficacies of cold plasma and Er:YAG laser on <i>Staphylococcus aureus</i> biofilm on titanium for nonsurgical treatment of peri‑implantitis

Abstract

Objectives: The aim of the present study was to compare antibiofilm efficacies of the laser in contact and noncontact application modes and cold atmospheric plasma (CAP) on Staphylococcus aureus biofilm grown on sandblasted, large grit, acid‑etched (SLA) titanium discs as an in vitro model of biofilm eradication on dental implant materials.

Methods:  S. aureus biofilm was matured on titanium discs for 7 days then, treated with contact and noncontact Er:YAG laser and CAP. Antibiofilm efficacy of laser and plasma treatments were evaluated with colony counting and safranin assays. Surface characteristics of titanium disc were analyzed with scanning electron microscopy and surface roughness measurements. Temperature distribution over titanium discs were presented for the thermal safety assessment of laser and plasma treatments.

Results: CAP resulted in 6‑log inactivation of S. aureus biofilm, whereas biofilm inactivation was determined as 1 and 2.7‑log for noncontact and contact laser treatments, respectively. Laser and plasma treatments did not cause any alterations on the roughness of titanium discs. Contact laser treatment caused a focal temperature increase up to 58°C, whereas plasma treatment led a uniform temperature distribution on the disc within safe limits.

Conclusion: CAP showed superior antibiofilm activity on 7‑day‑old S. aureus biofilm grown over SLA titanium discs, compared to contact and noncontact laser treatment without temperature increase and any damage to the surface of titanium discs.

Keywords: Cold atmospheric plasma, lasers, peri‑implantitis, titanium discs