Photodynamic Inactivation of Cariogenic Pathogens Using Curcumin as Photosensitizer

• Autor(a) principal: Araújo, Natália Costa
• Data de Publicação: 2017
• Outros Autores: De Menezes, Rebeca Ferraz, Carneiro, Vanda Sanderana Macêdo, Dos Santos-Neto, Alexandrino Pereira, Fontana, Carla Raquel [UNESP], Bagnato, Vanderlei Salvador, Harvey, Catherine Malinda, Gerbi, Marleny Elizabeth Martinez
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1089/pho.2016.4156; http://hdl.handle.net/11449/174558
• topic: dentin; dentistry; photodynamic therapy

Objective: This investigation assessed the susceptibility of Streptococcus mutans and Lactobacillus acidophilus to Photodynamic Therapy (PDT) when grown simultaneously in dentine carious lesions. Background data: PDT is a technique that utilizes light to activate photosensitizers in the presence of oxygen to produce reactive radicals. Materials and methods: A culture medium of 1% glucose, 2% sucrose, 1% young primary culture of L. acidophilus 108 CFU/mL, and S. mutans 108 CFU/mL was utilized to inoculate the bacterial induced caries on human dentine slabs. Different concentrations of the photosensitizer (0.75, 1.5, 3.0, 4.0, and 5.0 g/L) were activated through exposure to the light-emitting diode source with a central wavelength of 450 nm and a fluency of 5.7 J/cm2. Two light intensities (19 and 47.5 mW/cm2) were tested. Four different groups were analyzed: L-D- (control group), L-D+ (drug group), L+D+1 (PDT group 1, light intensity of 19 mW/cm2), and L+D+2 (PDT group 2, light intensity of 47.5 mW/cm2). ANOVA/Tukey tests were utilized to compare groups (α = 5%). Results: Both light intensities required 5.0 g/L of curcumin for significant bacterial reduction (p < 0.05). No significant effect was found for L-D+, thus proving the absence of a potential inherent toxicity. Conclusions: Curcumin has a toxic effect on microorganisms at appreciable concentrations upon photoactivation. However, it was required to use the maximum concentration of the drug for a successful procedure.