• Proceedings of the Optical Society of Korea Conference
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• 2004.02a
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• pp.348-349
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• 2004

• The Magazine of the IEIE
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• v.41 no.2
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• pp.49-58
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• 2014

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.1
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• pp.70-77
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• 2020

The present study is aimed to assess the effect of antimicrobial photodynamic therapy (aPDT) on Streptococcus mutans biofilm through teeth whitening light emitting diode (LED). Planktonic and dynamic biofilm state cultures of S. mutans were used. Erythrosine 20 μM/L was used as the photosensitizer. Irradiation was performed by exposing cultures to clinic and homecare whitening LEDs for 15 minutes. The viability was measured through Colony Forming Unit counts and confocal laser scanning microscopy. aPDT using whitening LEDs and erythrosine significantly decreased the CFU count of S. mutans compared to that in the control group. Dynamic biofilm group showed more resistant features to aPDT compared with planktonic state. Clinic and homecare whitening LED device showed similar antimicrobial effect. The whitening LED, which could irradiate the entire oral arch, showed a significant photodynamic effect on cariogenic S. mutans biofilm. aPDT mediated by erythrosine and LEDs used for teeth whitening exhibited promising antimicrobial activity.

• Korean Journal of Clinical Laboratory Science
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• v.47 no.4
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• pp.273-278
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• 2015

The purpose of this study was to evaluate the in-vitro efficacy of PDT using red light emitting diode (LED) with Radachlorin for biofilm inhibition of clinical Candida albicans isolates. The suspensions containing C. albicans at $9{\times}10^8CFU/mL$ were prepared on yeast nitrogen base containing 5% glucose. The biofilm formation was grown for 3 h after seeding suspensions each 100 ul on a 96-well plate and then supernatant was discarded. Each well was treated with $0.39{\mu}g/mL$ from $50{\mu}g/mL$ concentrations of Radachlorin on adherent biofilm. After a 30-minute incubation, light was irradiated for 30, 60, or 90 minutes using the following light source of wavelength 630 nm LED, at energy densities of 14, 29, and $43J/cm^2$. Afterwards, all supernatant was removed and dried. Adherent cells were stained with safranin O and dried. The cell viability was measured using a microplate reader at 490 nm. Also, a fluorescent signal on C. albicans was observed by saturation of a photosensitizer. In conclusion, a significant inhibition of 72.5% was observed to C. albicans on biofilm at the Radachlorin dose of $50{\mu}g/mL$ with 630 nm LED. The Photosensitizer (Radachlorin) was adequate at 30 minuttes for C. albicans. Overall, the results showed that inhibition of biofilm formation was Radachlorine dose-dependent. The results suggest that PDT, using Radachlorin with 630 nm LED, is able to decrease biofilm formation of C. albicans.

• Journal of the korean academy of Pediatric Dentistry
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• v.40 no.4
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• pp.241-246
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• 2013

The purpose of this study was to investigate the synergistic effects of erythrosine sensitized with a conventional halogen curing unit and sub-minimal bactericidal concentration(sub-MBC) of chorhexidine on bacterial viability of Streptococcus mutans in planktonic state. Sub-minimal bactericidal concentration of chlorhexidine was added into wells containing bacteria and erythrosine. The range of concentrations tested for chorhexidine was from 0.0000001% to 0.001%. The irradiation of the bacterial suspensions was performed for 15 sec with a conventional halogen curing unit light. In another set of experiment, the effects of 0.001% chlorhexidine were observed by adding chlorhexidine into wells containing the sub-minimal bactericidal concentration of erythrosine. At the concetration of 0.001% chlorhexidine, there were no antibacterial effects in the absence of erythrosine PDT(p < 0.05). At the concentraton of $1{\mu}M$ erythrosine, there was no photodynamic therapy effect in the absence of chlorhexidine(p < 0.05). But in the presence of sub-minimal bactericidal concentration of erythrosine with light exposure, the addition of 0.001% chlorhexidine increased the bactericidal rate(p < 0.05). A combination of erythrosine PDT with sub-MBC chlorhexidine resulted in a significant reduction in bacterial counts when compared to the case with the absence of chlorhexidine.

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.2
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• pp.120-127
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• 2020

The aim of this study was to evaluate the antimicrobial effect of photodynamic therapy (PDT) using plaque disclosing agent, 10 - 20 mM erythrosine, as a photosensitizer. Multispecies cariogenic biofilms containing Streptococcus mutans, Lactobacillus casei and Candida albicans were formed on hydroxyapatite disc. 20 μM, 10 mM and 20 mM erythrosine were applied as a photosensitizer for 3 minutes, and then light-emitting diode (LED) irradiated for 24 seconds. Colony-forming unit (CFU) were measured and biofilms were observed using confocal laser scanning microscopy (CLSM). CFU were significantly decreased in the PDT groups using 10 - 20 mM erythrosine (10 mM, 20mM) and the results were also confirmed by CLSM. This study confirms the high antimicrobial effect of photodynamic therapy using plaque disclosing agent as a photosensitizer.

• Polymer Science and Technology
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• v.22 no.2
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• pp.160-165
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• 2011

• Polymer Science and Technology
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• v.19 no.2
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• pp.138-145
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• 2008

• Journal of radiological science and technology
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• v.44 no.2
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• pp.141-146
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• 2021

This study aimed to explore whether photodynamic therapy using Radachlorin and diode laser is an effective inhibitor of Candida albicans. Suspensions of Candida albicans were obtained, inoculated in petri dishes with Radachlorin, and incubated for 30 min. Then, the laser light of a diode laser was irradiated at at energy densities of 3 J/cm², 5 J/cm², 7 J/cm². As a result, Candida albicans showed a killing rate of 91.5% at an energy density of 7 J/cm². This study found that photodynamic therapy using a Radachlorin and diode laser was effective for the inhibition of Candida albicans.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.3
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• pp.234-238
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• 2002

Photodynamic therapy (PDT) is based on a photochemical reaction which is initiated by light activation of a photosensitizer. The photosensitizer accumulates more in tumor tissues than in normal tissues and is activated with specific wavelength of light, usually laser. The photochemical reaction produces highly reactive oxygen products causing cytotoxiciy and vascular shutdown to the tumor. The advantages of PDT are its relative selective tumor destruction and tissue healing by regeneration, which can maintain important structures with very good functional and esthetic results. Therefore, PDT is considered as an alternative modality for cancers of the head and neck. In this article, we will report three cases of photodynamic therapy for treatment of oral leukoplakia, squamous cell carcinoma, and basal cell carcinoma of head and neck. It was observed that premalignant and malignant lesions responded well to the photodynamic therapy with Aminolevulinic acid (ALA) and $Foscan^{(R)}$. Photodynamic therapy can be considered as a new treatment method for the premalignant and malignant tumors in Oral and Maxillofacial Surgery.