Share Email Print

Proceedings Paper

The impact of antimicrobial photodynamic therapy on Streptococcus mutans in an artificial biofilm model
Author(s): Martin Schneider; Gregor Kirfel; Felix Krause; Michael Berthold; Olivier Brede; Matthias Frentzen; Andreas Braun
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

The aim of the study was to assess the impact of laser induced antimicrobial photodynamic therapy on the viability of Streptococcus mutans cells employing an aritificial biofilm model. Employing sterile chambered coverglasses, a salivary pellicle layer formation was induced in 19 chambers. Streptococcus mutans cells were inoculated in a sterile culture medium. Using a live/dead bacterial viability kit, bacteria with intact cell membranes stain fluorescent green. Test chambers containing each the pellicle layer and 0.5 ml of the bacterial culture were analyzed using a confocal laser scan microscope within a layer of 10 μm at intervals of 1 μm from the pellicle layer. A photosensitizer was added to the test chambers and irradiated with a diode laser (wavelength: 660 nm, output power: 100 mW, Helbo) for 2 min each. Comparing the baseline fluorescence (median: 13.8 [U], min: 3.7, max: 26.2) with the values after adding the photosensitizer (median: 3.7, min: 1.1, max: 9), a dilution caused decrease of fluorescence could be observed (p<0.05). After irradiation of the samples with a diode laser, an additional 48 percent decrease of fluorescence became evident (median: 2.2, min: 0.4, max: 3.4) (p<0.05). Comparing the samples with added photosensitizer but without laser irradiation at different times, no decrease of fluorescence could be measured (p>0.05). The present study indicates that antimicrobial photodynamic therapy can reduce living bacteria within a layer of 10 μm in an artificial biofilm model. Further studies have to evaluate the maximum biofilm thickness that still allows a toxic effect on microorganisms.

Paper Details

Date Published: 5 March 2010
PDF: 6 pages
Proc. SPIE 7549, Lasers in Dentistry XVI, 75490A (5 March 2010); doi: 10.1117/12.841809
Show Author Affiliations
Martin Schneider, Univ. Dental Clinic Bonn (Germany)
Gregor Kirfel, Univ. Bonn (Germany)
Felix Krause, Univ. Dental Clinic Bonn (Germany)
Michael Berthold, Univ. Dental Clinic Bonn (Germany)
Olivier Brede, Univ. Dental Clinic Bonn (Germany)
Matthias Frentzen, Univ. Dental Clinic Bonn (Germany)
Andreas Braun, Univ. Dental Clinic Bonn (Germany)

Published in SPIE Proceedings Vol. 7549:
Lasers in Dentistry XVI
Peter Rechmann D.D.S.; Daniel Fried, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?