ELIMINATION OF BACTERIA ON DIFFERENT IMPLANT SURFACES THROUGH PHOTOSENSITIZATION AND SOFT LASER - AN IN-VITRO STUDY

Microbiologic examinations of implants have shown that certain microor ganisms described as periodontal pathogens may have an influence on th e development and the progression of peri-implant disease. This experi mental study aimed to examine the bactericidal effect of irradiation w ith a soft laser on bacteria associated with peri-implantitis followin g exposure to a photosensitizing substance. Platelets made of commerci ally pure titanium, either with a machined surface or with a hydroxyap atite or plasma-flame-sprayed surface or with a corundum-blasted and e tched surface, were incubated with a pure suspension of Actinobacillus actinomycetemcomitans or Porphyromonas gingivalis or Prevotella inter media. The surfaces were then treated with a toluidine blue solution a nd irradiated with a diode soft laser with a wave length of 905 nm for 1 min. None of the smears obtained from the thus treated surfaces sho wed bacterial growth, whereas the smears obtained from surfaces that h ad been subjected to only one type of treatment showed unchanged growt h of every target organism tested (P<0.0006). Electron microscopic ins pection of the thus treated platelets revealed that combined dye/laser treatment resulted in the destruction of bacterial cells. The present in vitro results indicate that lethal photosensitization may be of us e for treatment of peri-implantitis.