Objective: To test the antiadherent and antibacterial properties of surface modification of orthodontic wires with photocatalytic titanium oxide (TiO2).
Materials and Methods: TiO2 was coated on the surface of the orthodontic wires by a sol-gel thin film dip-coating method. Bacterial adhesion to the wires was evaluated by the weight change of the wires. The antibacterial activity of the surface-modified orthodontic wires was demonstrated by the dilution agar plate method for Streptococcus mutans and spectrophotometry for Porphyromonas gingivalis.
Results: The orthodontic wires coated with the photocatalytic TiO2 showed an antiadherent effect against S. mutans compared with the uncoated wires. The bacterial mass that bound to the TiO2-coated orthodontic wires remained unchanged, whereas that of the uncoated wires increased by 4.97%. Furthermore, the TiO2-coated orthodontic wires had a bactericidal effect on S. mutans and P. gingivalis, which cause dental caries and periodontitis, respectively. The antiadherent and antibacterial mechanisms of TiO2 to break down the cell wall of those bacteria were revealed by scanning electron microscopy.
Conclusion: The surface modification of orthodontic wires with photocatalytic TiO2 can be used to prevent the development of dental plaque during orthodontic treatment.
