The Efficacy of Photodynamic Inactivation with Laser Diode on Staphylococcus aureus Biofilm with Various Ages of Biofilm

Abstract

<jats:p>Biofilms are able to casue microorganisms to be 80% more resistant to antibiotics. The extracelullar polymeric substance (EPS) in biofilm functions to protect bacteria, making it difficult for antibiotics to penetrate the biofilm layer. This study aims to determine the effective- ness of photodynamic inactivation with blue diode laser to reduce Staphylococcus aureus biofilm at various ages of biofilms. The light source is a 403 nm blue diode laser with an energy power of about 27.65±0.01 mW. The study was designed with two groups: Group C was the untreated control group with variations in age of biofilms (0; 6; 11; 17; 24; 32; 40 and 48) hours; Group T was a laser treatment group with variations in age of biofilm and energy density (4.23; 8.46; 12.70; 16.93 and 21.16) J/cm2. Biofilm reduction measurement method using ELISA test was performed to calculate OD595 value. The statistical analysis results of variance showed that there was an influence of biofilm age and irradiation energy density of laser on biofilm reduction. Optical density analysis showed the most optimum biofilm reduction happened when biofilm age is perfectly constructed (about 17 hours) and with 91% reduction. The longer biofilm age lived among those biofilms, the greater the reduction. The results of the Scanning Microscope Electron and fluorescent microscope measurement showed destruction site of the EPS biofilm and bacterial cell death. So, the activated photodynamic with 403 nm laser diode is effective to reduce the Staphylococcus aureus biofilm in the maturation phase.</jats:p>

Comparison of the antimicrobial reduction effect of photodynamic inactivation with the addition of chlorophyll and curcumin photosensitizer in Aggregatibacter actinomycetemcomitans and Enterococcus faecalis

“…Diode laser irradiation was carried out with variations in the length of the irradiation time of 30, 60, 90, 120, 150, and 180 seconds. The energy density value can be calculated using equation 1 9 :…”

“…Photodynamic inactivation (PDI) is a method of inactivating microorganisms by utilizing light to activate a photosensitizer (PS) agent that produces reactive oxygen species (ROS), causing cell lysis. 7,8 The suitability of the light spectrum with the PS absorption spectrum is the key to photophysical reactions, namely the absorption of light energy by PS agents, which will trigger photochemical and photobiological reactions to produce antimicrobial effects 9,10 and biomodulation. 11 PS is a light-sensitive molecule that plays a role in absorbing light energy.…”

Antimicrobial photodynamic therapy (aPDT) for biofilm treatments. Possible synergy between aPDT and pulsed electric fields

“…Several authors have been reported that aPDT-generated ROS has many possible targets on biofilms, mainly against EPS matrix [ 99 ] that includes the DNA [ 100 ], lipids [ 101 ], proteins [ 102 , 103 ] and extracellular polysaccharides [ 104 ]. In addition [ 105 ], showed the efficacy of the aPDT against several stages of biofilm development. Thus, they designed experiments to analyze the effect of different light doses (4.23; 8.46; 12.70; 16.93 and 21.16 J/cm 2 ) against several ages of S. aureus biofilms (0; 6; 11; 17; 24; 32; 40 and 48 hours).…”

Degradation of Fusobacterium nucleatum biofilm and quantity of reactive oxygen species due to a combination of photodynamic therapy and 2.5% sodium hypochlorite

“…The larger the photon intensity and the longer the exposure, the more photosensitizer will be activated to produce various ROS that has an effect on the number of bacterial deaths. 24 One of the most common and frequently used root canal irrigation agents to date is 2.5% NaOCl. Bacteria can penetrate the root dentinal tubules to a depth of 1000 µm, while the irrigation disinfection material only reaches a depth of 100 µm.…”