Silver doped titanium dioxide nanoparticles as antimicrobial additives to dental polymers

The objectives of this in vitro study were to produce a filled resin containing Ag-TiO₂ filler particles and to test its antibacterial properties.

Ag-TiO₂ particles were manufactured using the ball milling method and incorporated into an epoxy resin using a high speed centrifugal mixer. Using UV/vis spectrophotometry investigations were performed to assess how the photocatalytic properties of the Ag-TiO₂ particles are affected when encased in resin. Adopting the bacteria colony counting technique, the antibacterial properties of Ag-TiO₂ particles and Ag-TiO₂ containing resins were assessed using Streptococcus mutans under varying lighting conditions.

Ag doping of TiO₂ results in a band gap shift towards the visible spectrum enabling Ag-TiO₂ to exhibit photocatalytic properties when exposed to visible light. Small quantities of Ag-TiO₂ were able to produce a bactericidal effect when in contact with S. mutans under visible light conditions. When incorporated into the bulk of an epoxy resin, the photocatalytic properties of the Ag-TiO₂ particles were significantly reduced. However, a potent bactericidal effect was still achieved against S. mutans.

Ag-TiO₂ filled resin shows promising antimicrobial properties, which could potentially be used clinically.