An in vitro evaluation of wettability and microbial adhesion of 316L stainless steel orthodontic archwires coated with Ag/PTFE nanoparticles

Abstract

Objective: This study investigated how silver/polytetrafluoroethylene (Ag/PTFE) nanoparticle coatings influence the surface wettability and bacterial adhesion of 316L stainless steel orthodontic archwires against Streptococcus mutans and Staphylococcus aureus. Material and Methods: Stainless steel archwires were ultrasonically cleaned, sterilized, and coated using RF sputtering. The coated surfaces were characterized using XRD and AFM; wettability and bacterial adhesion were analyzed using contact-angle measurements and microbial assays. Results: The Ag/PTFE coatings produced uniform, smooth layers, increasing the contact angle from 72.96° (uncoated) to 135.35° (30 min sputtering) and reducing roughness from 45 nm to 18 nm. Adhesion of S. mutans and S. aureus dropped to 1.54 and 2.16 CFU/mL, respectively. Conclusion: RF-sputtered Ag/PTFE coatings enhanced hydrophobicity and reduced bacterial adhesion, suggesting improved oral hygiene during orthodontic treatment.

KEYWORDS

Antiadherent; Nanoparticles; Radio frequency; Roughness; Wettability.