Curcumin nanoparticles and blue laser irradiation in photothermal inactivation of selected oral pathogens in vitro
Abstract
In last years, devices emitting laser beam in blue spectrum has been the subject of substantial research also in dentistry. But improvement of bactericidal effect might be theoretically possible using exogenous chromophore under the terms of photothermal therapy.
With respect to the colour, curcumin seems be a suitable chromophore for this method and we decided to use curcumin nanoparticles and evaluate their effect as a photosensitizer for 445 nm laser in effectiveness against selected G+ and G- bacteria in vitro. Curcumin nanoparticles were prepared using ultrasound assisted solvent-antisolvent precipitation.
Diode laser 445 nm (SIROLaser Blue) was used as a source of laser irradiation (100mW, 1 min. exposition time, energy density 7,68J/cm2). Bacterial strains of Porphyromonas gingivalis, Parvimonas micra and Enterococcus faecalis were cultivated on solid media in marked areas covered by curcumin nanoparticles.
After laser irradiation and subsequent anaerobic cultivation, the bacterial growth was evaluated. Irradiated areas without contact with curcumin nanoparticles showed intact bacterial colonies.
Completely different quality was detectable in cases of irradiated colonies growing in contact with curcumin nanoparticles. Destruction of bacterial colonies was clearly visible and repeated cultivation of taken material was without positive response confirming presence of non-living cells inside of colonies.
Results of our preliminary study showed promising direction of laser photothermal therapy using curcumin nanoparticles in reduction or elimination of oral microflora especially in locations with poor access for classic therapeutic effect.