Physical, mechanical and antibacterial properties of the orthodontic adhesive doped with S-TiO₂

Orthodontic adhesive doped with sulfur-modified TiO₂ promotes antibacterial effect. The objective of the study was to characterize the physical, mechanical and antibacterial properties of the orthodontic bracket adhesive, doped with modified titanium dioxide nanoparticles. Sulfur-doped TiO₂ was synthetized and morphological topography was analyzed with TEM and SEM imaging. The catalytic performance during the degradation of rhodamine B was assessed. Nanomaterial was added at four concentration (1, 3, 6, and 10 wt%) to a commercial orthodontic adhesive. The shear bond strength and microhardness of a resin-based orthodontic adhesive containing S-TiO₂ were evaluated. The inhibitory effect of the pure and doped adhesives against Escherichia coli and Streptococcus mutans was examined. As the results, the highest antimicrobial activity and good adhesive properties were noticed for light-cured orthodontic adhesive doped with 3% of S-TiO₂. In this case, orthodontic adhesives with strong and long-lasting bactericidal properties can be created through the incorporation of modified TiO₂ without negatively influencing microhardnesses, and bonding ability. White spot lesion and demineralization, which occurs very often in patients during orthodontic treatment, can be therefore minimized.