IADR Abstract Archives
Optical/Biological Properties of New Acid Photosensitizer for Antimicrobial Photodynamic Therapy
Objectives: Antimicrobial photodynamic therapy (aPDT) is an effective adjuvant treatment for periodontal disease. Researches focusing new photosensitizers for aPDT in oral cavity may contribute to better treatment results. The aim of this in vitro research was to test the optical properties of new acid blue photosensitizer for aPDT and its toxicity in cell culture.
Methods: For optical test, absorbance of new dye (ND – pH 1) and conventional dye (CD – pH 5.5) were compared using a spectrophotometer. Photodegradation rate was measured using light at 660 nm. For cytotoxicity test, human gingival fibroblasts (HGF - 104 – 5th passage), obtained by primary culture, were cultured on human dentin blocks which received each treatment. Groups were C (control – no treatment), ND - aPDT with new dye (laser 660nm, 30mW, 45J/cm2, 30s), CD - aPDT with conventional dye (same parameters). Cells were counted in scanning electron microscope images by a blinded calibrated examiner. Statistical analysis was performed with repeated measures ANOVA and Tukey’s tests (p≤0.05).
Results: Results showed that both photosensitizers had absorbance bands at 660nm. A small photodegradation rate was encountered for CD and no photodegradation for ND. There was a higher number of cells after 72h of growth (p≤0.05) without differences among groups (p≥0.05).
Conclusions: In conclusion, ND has absorption band in 660nm compatible to diode lasers, but no photodegradation on this band. ND is not cytotoxic for human gingival fibroblasts.
Methods: For optical test, absorbance of new dye (ND – pH 1) and conventional dye (CD – pH 5.5) were compared using a spectrophotometer. Photodegradation rate was measured using light at 660 nm. For cytotoxicity test, human gingival fibroblasts (HGF - 104 – 5th passage), obtained by primary culture, were cultured on human dentin blocks which received each treatment. Groups were C (control – no treatment), ND - aPDT with new dye (laser 660nm, 30mW, 45J/cm2, 30s), CD - aPDT with conventional dye (same parameters). Cells were counted in scanning electron microscope images by a blinded calibrated examiner. Statistical analysis was performed with repeated measures ANOVA and Tukey’s tests (p≤0.05).
Results: Results showed that both photosensitizers had absorbance bands at 660nm. A small photodegradation rate was encountered for CD and no photodegradation for ND. There was a higher number of cells after 72h of growth (p≤0.05) without differences among groups (p≥0.05).
Conclusions: In conclusion, ND has absorption band in 660nm compatible to diode lasers, but no photodegradation on this band. ND is not cytotoxic for human gingival fibroblasts.