Background and Purpose: Antimicrobial photodynamic therapy using Methylene blue (MB-PDT) has been proposed as an adjunctive to scaling and root planing (SRP) to provide preferable results for the treatment of periodontitis. The multi-factor mechanism of aPDT action correlates with various influencing components such as the photosensitizer and the light delivery system. The paper aims to review the recorded parameters of MB-PDT from clinical trials of periodontitis which may serve to improve the treatment of periodontal diseases. Materials and Methods: PubMed search engine was used to identify human clinical trials of PDT in dentistry. After applying specific keywords, additional filters, exclusion criteria, the initial number of 17378 was reduced to 12. Results: More than half of the articles of SRP + MB-PDT presented better results [pocket depth (PD) reduction, clinical attachment level (CAL) gain, etc.] compared to SRP alone in the treatment of periodontitis. Conclusions: While more clinical evidence is needed, recent studies demonstrate that MB-PDT combined with SRP show a greater potential as a treatment of periodontal diseases in comparison to SRP alone.

Photodynamic therapy (PDT) has been widely used in clinical fields and done by three components: photosensitizers (PSs), light and oxygen. Under the action of PS as an energy transforming media, the light energy is converted to chemical energy to make effects on target. In the process of PDT, its effect is determined a lot by the parameter of light and the characteristics of PSs. With the development of light source and photosensitizer, the application of PDT has been investigated in oral diseases. This review mainly focused on the effect of PDT on non-tumor diseases of oral cavity, including endodontic, periodontal and mucosal problem. Compared with the normal therapy, the combination therapy with PDT could obtain better efficacy. It was suggested that PDT showed great advantages as an adjuvant therapy in the above oral diseases. Through a further improvement, PDT is expected to play an increasingly important role on the oral disease treatment in the future.

Photodynamic therapy(PDT) is recently developed as an effective treatment for malignant disease. Carboplatin, a less nephrotoxic analog of cisplatin, has been widely used for the treatment of multiple malignancies. In this study, we investigated the cytotoxic and apoptotic effect of combined modality of photofrin mediated PDT with cisplatin and carboplatin on KB cell human oral cancer cell line in vitro. The a ttached KB cells were incu bated with c isplatin(0.04mg/ml) and carboplatin(0.02mg/ml) for 24h at 37℃ and followed by photosensitization with photofrin for 6h and laser irradiation with 630nm LED at an intensity of 2.0 J/cm2 for activating photofrin for 15min. Then MTT assay and SYTO 16 green & Propidium iodide (PI) double staining were used respectively to measure the cytotoxicity and nuclear morphology at 24h after PDT. This study demonstrates that the combined modality with carbopaltin resulted in enhanced apoptotic cell death as well as cytotoxic e ffect on KB c ells in vitro, which s uggests the feasibility of combined modality and the possibility o f reducing the effective dosage of photofrin and carboplatin and lowering the side effects on normal cells

The organotypic raft culture model has been shown to be a useful method for examining the effects of biochemical manipulation on various epithelial cell types, using in vitro conditions that simulate the in vivo environment of the tissue of origin. To investigate this method as a model for photodynamic therapy (PDT), we cultures the oral squamous carcinoma cell line YD-10B on fibroblast-containing collagen gels at the air-liquid interface and assessed the efficacy of PDT using a photosensitiser 5-ALA-hexenyl ester. PDT effect on YD-10B organotypic raft cultures after twenty- four hours was determined. The number of residual cells was significantly reduced in comparison to control at all four different conditions. PCNA immunostaining and TUNEL assay revealed that PDT inhibited cell proliferation and increased apoptosis. These findings suggest that the organotypic raft culture model provides an effective and rapid laboratory method of investigating strategies for PDT on oral precancerous lesions and squamous cell carcinomas

We conducted a series of in vitro experiments to evaluate the anticancer effect of photodynamic therapy using hypericin and 532㎚ DPSS (diode pumped solid state laser). The cultured KB cells were treated with serial concentrations of hypericin ranging from 0.01㎍/㎖ to 5㎍/㎖ (two-fold dilution) with variable laser dosage (10J, 20J, 30J). The cell viability was evaluated by MTT assay. The type of cell death was detected by fluorescent microscope using Hoechst 33342 / PI (propidium iodide) stain methods. In this study, IC50 value with hypericin-mediated PDT with 10J DPSS laser was 35 ng/ml. The maximum cytotoxicity with Photofrin II-based PDT was observed at high drug concentrations(> 90 ng/ml) independent with laser dose. And the in vitro PDT effects depended on the laser dose and drug concentrations were displayed by the difference in the type of cell death, namely apoptosis or necrosis. According to this result, the hypericin based photodynamic therapy with DPSS laser was effective photodynamic therapy.

PDT is an establi shed cancer treatment modali ty , This can be attributed to the attractive basic concept of PDT; the combina ti on 0[' two ther a peut ic agents, a photosensitizing drug and light, which are r elatively harmless by themselves but combined ultimately ca use more 0 1' less selective tumor destruction, The bacteriochlorophyll - derivatived photosensitizers are known to be s ta ble and hi ghly efficient‘ In this s tudy, we conducted a series of experiments to develope the ligh t induced anticancer drugs against oral cancer cell ‘ We tested the cytotoxicity of the hydroxybact eriochlorine by MTT a ssay and observed the cell death pattern (apoptosis or necrosis) after PDT by hoechst 33342 and propidium iodide s taining methods , IC50 value of the hydroxybacteriochlorine was 31,3ngjm.Q, At higher doses of hydroxybacteriochlorine () 60 ng/ 뼈) ， cancer cells died exc lus ively by nec rosis after PDT By contrast, at IC50 value, h ydroxybacteri ochlorine in duced ca ncel' cell to undergo a poptotic cell death The induction begins approximately 6 hours after PDT We investigates int racellu la r localizati on of hydroxybact eri ochl orine by ora l cancer cell via confocal laser scanning microscopy, Oral can cer cells dual-stained with hydroxybactel' iochlorine and organelle-specific fluoresc ence probes (Mi totracker, Lysotracker , ER- Trac ker) revealed an int l'acellula l' flu orescence distribution restrict ed to cytoplasmic compartments with no detectable fl uoresce nce in the nucleus Confocal images of cells containing hydroxybacteriochlorine were never overlap to mi tochondria, lysosome, endoplasmic l'eticulum when digitally overlapped with the organelle-specific flu orescence probe images of the same cells , These resul ts demonstrat ed that the hydroxybacteriochlorine may have a function as a photosens it izer and cytotoxicity hydroxybactel' ioc hlorine for oral ca ncer cell is more sensitive than head & neck cancer cell or cervical cance l' cell Ther efore PDT using hydroxybact eriochlorine is suitable treatment for oral cavity car cinoma patients.

This study was conducted to test the anticancer effect of photodynamic therapy using chlorophyll derivative (9-HpbD-a) and 632nm diode laser. Human SNU 1041 cells were seeded into 96 well plate of 104cells/well and cultured for 24 hours. Cells were washed with media containing various concentration of 9-HpbD-a ranging from Oug/ml to 3.75ug/ml. Then 932 nm diode laser was given at various lasering time setting, and at various starting time after ini tial 24 hours of culture. The treated cells were incubated 48 hours and tetrazolium-based colorimetric(M'IT) assay was done to measure the viability of cells For in vivo study, SNU- 1041 cells were xenografted into the back of nude mouse. When the xenografted tumors grew up to 400-600 mm3, the animals were randomly placed into 4 groups: Group 1 (n=20) , PDT group, interstitial injection of 9-HpbD- a (47 ug/kg) followed by irradiation with 3.2 J/c야 of light 6 hours after then i띠 ection; Group II (n=lO) , irradiation with 3.2 J/crrf of light using diode laser; Group III (n=lO), in terstitial injection of 9-HpbD- a only(47 ug/kg); Group IV (n=lO), normal control group. The viability of cells was de creased with increasing lasering time No significant difference of cell viability was noted by variously delayed starting time of lasering. PDT effects were observed in the xenografted nude mouse model Group IV (no 9-HpbD-a, no laser irradiation) was a control group which showed a continuous tumor growth. Group III (9-HpbD-a i띠 ection only) showed no response, Group II (laser irradiation only) sho￦ed 1 complete remission out of 10 (10%) , Group 1 (9-HpbD-a and laser irradiation) showed 13 cpmplete remission out of 20 (65%) , Group 1 showed significant remission rate, comparing to other groups (p<0.05). This study demonstrated anticancer effect of photodynamic therapy using 9-HpbD-a and 632nm diode laser on human squamous cell carcinoma cell line.

We conducted a series of in vitro experiments to evaluate the efficiency of photodynamic therapy on head and neck cancer cell using hydroxybacteriochlorine from photosynthetic bacteria. We tested the cytotoxicity of the hydroxybacteriochlorine by MTI assay and observed the cell death pattern(apoptosis or necrosis) after PDT by hoechst 33342 and propidium iodide staining methods IC50 value of the hydroxybacteriochlorine was 0.22μg/rrúi. At higher doses of hydroxybacteriochlorine () 0.6μg/rrúi) , cancer cells died exclusively by necrosis after PDT. By contrast, at IC50 value, hydroxybacteriochlorine induced cancer cell to undergo apoptotic cell death. The induction begins approximately 6 hours after PDT. We investigates intracellular localization of hydroxybacteriochlorine by head & neck cancer cell via confocal laser scanning microscopy. Head & neck cancer cells dual-stained with hydroxybacteriochlorine and a panel of organelle- specific fluorescence probes (Mitotracker, Lysotracker, ER-Tracker) revealed an intracellular fluorescence distribution restricted to cytoplasmic compartments with no detectable fluorescence in the nucleus Confocal images of cells containing hydroxybacteriochlorine were never overlap in subcellular organelle fluorescence when digitally over layed with the organelle-specific fluorescence probe images of the same cells. These results demonstrated that the hydroxybacteriochlorine may have a function as a photosensitizer.

Photodynamic therapy is a non-invasive cancer therapy that has recently attracted much attention in the field of cancer treatment. This study is an experiment to observe the effect of laser dose difference in photodynamic therapy. Murine breast cancer cells, EMT6 cells, were used to generate tumor bearing mouse models. The experimental group was divided into 5 groups as control group, laser 100 J/cm2, 200 J/cm2, 300 J/cm2 and 400 J/cm2 irradiation group. Photofrin was administered intraperitoneally and after 48 hours, laser irradiated on tumor with energy 0-400 J/cm2. the tumor volume was measured with a digital caliper on day 0, day 2, day 4, day 8 and day 12. The volume of tumor after photodynamic therapy was increased in the control group, laser 100 J/cm2 irradiation group and laser 200 J/cm2 irradiation group until day 12 after irradiation. Both the laser 300 J/cm2 irradiated group and the laser 400 J/cm2 irradiated group showed a decrease in the tumor volume from 2 to 12 days after irradiation. These results suggested that treatment effect will be obtained at a dose of 300 J/cm2 or more in the experiment using the tumor bearing mouse model and photoprin.