Antimicrobial photodynamic therapy against a dual-species cariogenic biofilm using a ruthenium-loaded resin-based dental material.
Photodiagnosis Photodyn Ther
; 46: 104019, 2024 Apr.
Article
in En
| MEDLINE
| ID: mdl-38395246
ABSTRACT
BACKGROUND:
Streptococcus mutans and Candida albicans are associated with caries recurrence. Therefore, this study evaluated the combination of a Ru(II)-loaded resin-based dental material (RDM) and antimicrobial photodynamic therapy (aPDT) against a dual-species biofilm of S. mutans and C. albicans.METHODS:
An aPDT protocol was established evaluating Ru(II)'s photocatalytic activity and antimicrobial potential under blue LED irradiation (440-460 nm, 22.55 mW/cm2) at different energy densities (0.00, 6.25, 20.25, 40.50 J/cm2). This evaluation involved singlet oxygen quantification and determination of minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal concentration (MBC/MFC). The biofilm was grown (72 h) on resin disks prepared with Ru(II)-doped RDM (0.00, 0.56, or 1.12 %) and samples were exposed to aPDT or dark conditions. The biofilm was then harvested to analyze cell viability (CFU counts) and formation of soluble and insoluble exopolysaccharides.RESULTS:
The photocatalytic activity of Ru(II) was concentration and energy density dependent (p < 0.05), and MIC/MBC values were reduced for the microorganisms after LED irradiation (40.5 J/cm2); therefor, this energy density was chosen for aPDT. Although incorporation of Ru(II) into RDM reduced the biofilm growth compared to Ru(II)-free RDM for both species in dark conditions (p < 0.05), aPDT combined with an Ru(II)-loaded RDM (0.56 or 1.12 %) potentialized CFU reductions (p < 0.05). Conversely, only 1.12 % Ru(II) with LED irradiation showed lower levels of both soluble and insoluble exopolysaccharides compared to Ru(II)-free samples in dark conditions (p < 0.05).CONCLUSIONS:
When the Ru(II)-loaded RDM was associated with blue LED, aPDT reduced cell viability and lower soluble and insoluble exopolysaccharides were found in the cariogenic dual-species biofilm.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Photochemotherapy
/
Ruthenium
/
Streptococcus mutans
/
Candida albicans
/
Microbial Sensitivity Tests
/
Photosensitizing Agents
/
Biofilms
Language:
En
Journal:
Photodiagnosis Photodyn Ther
Journal subject:
DIAGNOSTICO POR IMAGEM
/
TERAPEUTICA
Year:
2024
Document type:
Article
Affiliation country:
Canada