Photodynamic effects of toluidine blue on human oral keratinocytes and fibroblasts andStreptococcus sanguis evaluated in vitro

✍ Scribed by Soukos, Nikolaos S.; Wilson, Michael; Burns, Tracy; Speight, Paul M.

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 518 KB
• Volume: 18
• Category: Article
• ISSN: 0196-8092
• DOI: 10.1002/(sici)1096-9101(1996)18:3<253::aid-lsm6>3.0.co;2-r

✦ Synopsis

Background and Objective: Some oral bacteria are susceptible to killing by red light after their sensitization with toluidine blue 0 (TBO). The photochemotherapy of periodontal disease in vivo would require a therapeutic window where bacteria could be killed without adjacent normal tissue damage.

Study DesignIMaterials and Methods:

The laser-induced effects of TBO on normal human gingival keratinocytes and fibroblasts have been studied in vitro. For the assessment of viability, the CellTiter 96 Tv AQueous Non-Radioactive Cell Proliferation Assay was used. Results: TBO was cytotoxic at low concentrations (5.0 pg/ml). Sensitization of keratinocytes and fibroblasts with 2 and 5.0 pglml TBO, respectively, for 5 min and exposure to light from a 7.3 mW HeliundNeon (HeNe) laser for up to 2 min (0.8765) did not reduce cell viability. However, killing of Streptococcus sanguis was achieved following exposure to HeNe light for 75 sec (0.5475) in the presence of TBO at a concentration of 2.5 pg/ml.

Conclusion:

The development of a system for the lethal photosensitization of bacteria responsible for periodontal disease may be possible. o 19% Wiley-Liss, Inc.