• Journal of Biomedical Engineering Research
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• v.14 no.1
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• pp.17-22
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• 1993

Radiation-induced fibrosarcoma tumors were grown on the flanks of C3H mice. The mice were divided intro two groups. One group was injected with Photofrin II, intravenously (2.5mg/kg body weights). The other group received no Photofrin E Mice from both groups were irradiated for approximately 15 minutes at 100,300, or $500{\;}mW/\textrm{cm}^2$ with the argon (488nm/514.5 nm), dye(628nm) and gold vapor (pulsed 628 nm) laser light. A photosensitizer behaved as an added absorber. Under our experimental conditions, the presence of Photofrin II increased surface temperature by at least 40% and the temperature rise due to $300{\;}mW/\textrm{cm}^2$ irradiation exceeded values for hyperthermia. Lights and temperature distributions with depth were estimated by a computer model. The model demonstrated the influence of wavelength on the thermal process and proved to be a valuable tool to investigate internal temperature rise.

• The Journal of the Korean dental association
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• v.53 no.12
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• pp.906-909
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• 2015

Peri-implantitis is the inflammatory process, such as edema, bleeding, pus, of the mucosa surrounding dental implants. As the symptoms become severe, the surrounding bone is absorbed causing the implant surface to be exposed. Clinicians treat periimplantitis in various ways since a gold standard for the treatment of peri-implantitis has not been established. Various treatment methods include mechanical, chemical surface treatment and surgical excision, and recently decontamination of the implant surface using various types of lasers has been proposed. Thus, this study reviews the types of lasers and its effects that can be used for the treatment of peri-implantitis.

• Journal of Oral Medicine and Pain
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• v.19 no.1
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• pp.17-23
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• 1994

This study was performed to investigate the biostimulation effects of low level laser therapy (LLLT) on the fungus, Candida albicans, during the short term of cell cycle. Samples were divided into 6 groups which were P7, P9, P11, P15< CW and CO. All samples were irradiated for 1 minute with 2 hours of elapsed time during about 27 hours of the cell cycle of Candida albicans, and the optical density was assessed by spectrophotometry every 2 hours. It was found that there was no difference between the control and any other groups irradiated with 2 hours of short interval.

• Korean journal of dermatology
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• v.56 no.10
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• pp.636-639
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• 2018

Mycosis fungoides is the most common type of cutaneous T-cell lymphoma. Patients with early stage disease usually respond well to conventional therapies, with a relatively favorable prognosis. However, a few patients are refractory to treatment and need alternative strategies, even at the patch and plaque stages. We report the case of a middle-aged woman with long-standing and refractory mycosis fungoides that responded to combination therapy with the 308-nm excimer laser and oral alitretinoin.

• Medical Lasers
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• v.8 no.2
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• pp.94-96
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• 2019

Burns are one of the most extensive injuries of soft tissues as well as skin, occasionally resulting in extensive, deep wounds and death. Burn wounds can lead to severe physical and psychological distress because of excessive scarring and skin contractures. Treatment of burn wounds has always been a challenging problem and many different methods have been used to treat such injuries. We report here on treating a patient with a burn wound using 830-nm light emitting diode (LED) phototherapy combined with epidermal growth factor (EGF) solution. After five daily sessions of LED with EGF solution treatment, the patient demonstrated nearly complete improvement with no remarkable side effects. We suggest that LED phototherapy combined with EGF solution could be an effective and safe treatment option for treating burn wounds.

• Journal of Chest Surgery
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• v.30 no.12
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• pp.1237-1241
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• 1997

Tracheal stenosis is a difficult disease entity to manage. Laser ablation is one effective treatment for treacheal stenosis and can be utilized if tracheal reconstructive surgery is impossible. Potassium titanyl phosphate laser, transmitted via flexible quartz fiber, can be precisely manipulated through flexible bronchoscope under local anesthesia. We treated 7 patients with trach al and broncheal lesion under local anesthesia with KTP laser from January 1995 to July 1996. The patients included three males and four females. The age of patients ranged from 22 to 66 years with a mean of 43.7 years The etiology of tracheal stenosis in patients was stenosis after tracheostomy(3 cases), prolong inturbation in cases of sepsis(1 cases), and the recurrence of lung cancer within endobronchial lesion(2 cases). In the cases of tracheal stenosis treated with laser ablation, there were 2 cases of recurrence of stenosis at the anastomosis site after the operation, 3 cases of stenosis at tracheostomy site, and 2 cases of local recurrence of lung cancer. The site of the tracheal stenosis was the balloon site of the tracheostomy tube(3-4cm inferior to the tracheostomy site, 2-3cm superior to the carina) and the anastomosis site that were narrowed to less than 5mm(4 cases). For the stenosis lesion in the endobronchial area, there were 2 patients with a lesion at the anterior wa l, 1 patient with a lesion at the posterior wall, 2 patients with circumferential stenosis. Laser ablation time was 25.4 $\pm$5.9min and used energy was 1768 $\pm$365J. We have used KTP laser via (lexible bronchoscope without major complications. Adjuvant radiation therapy may prevent fibroblast proliferation which leads to restenosis. In three patients of restenosis after laser ablation, adjuvant irradiation started within 4 hours after laser ablation, and the radiation doses were 1500cGy given in five fraction. In patients with adjuvant radiation therapy, stenosis has not recurred

• Journal of Periodontal and Implant Science
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• v.40 no.3
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• pp.105-110
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• 2010

Purpose: It has been reported that low-level semiconductor diode lasers could enhance the wound healing process. The periodontal ligament is crucial for maintaining the tooth and surrounding tissues in periodontal wound healing. While low-level semiconductor diode lasers have been used in low-level laser therapy, there have been few reports on their effects on periodontal ligament fibroblasts (PDLFs). We performed this study to investigate the biological effects of semiconductor diode lasers on human PDLFs. Methods: Human PDLFs were cultured and irradiated with a gallium-aluminum-arsenate (GaAlAs) semiconductor diode laser of which the wavelength was 810 nm. The power output was fixed at 500 mW in the continuous wave mode with various energy fluencies, which were 1.97, 3.94, and 5.91 $J/cm^2$. A culture of PDLFs without laser irradiation was regarded as a control. Then, cells were additionally incubated in 72 hours for MTS assay and an alkaline phosphatase (ALPase) activity test. At 48 hours post-laser irradiation, western blot analysis was performed to determine extracellular signal-regulated kinase (ERK) activity. ANOVA was used to assess the significance level of the differences among groups (P<0.05). Results: At all energy fluencies of laser irradiation, PDLFs proliferation gradually increased for 72 hours without any significant differences compared with the control over the entire period taken together. However, an increment of cell proliferation significantly greater than in the control occurred between 24 and 48 hours at laser irradiation settings of 1.97 and 3.94 $J/cm^2$ (P<0.05). The highest ALPase activity was found at 48 and 72 hours post-laser irradiation with 3.94 $J/cm^2$ energy fluency (P<0.05). The phosphorylated ERK level was more prominent at 3.94 $J/cm^2$ energy fluency than in the control. Conclusions: The present study demonstrated that the GaAlAs semiconductor diode laser promoted proliferation and differentiation of human PDLFs.

• Journal of Periodontal and Implant Science
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• v.27 no.3
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• pp.469-478
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• 1997

The purpose of this study was to evaluate the structural change of root surface and the occlusion of dentinal tubule following $CO_2$ laser treatment. Seven extracted healthy human premolar werw curetted, sectioned, and four specimens were randomly assigned to each of 6 different treatment groups : 1) untreated EDTA etched control: 2) root plande only: 3) $CO_2$ laser treated with 2W mode 6(10msec/pulse, 20pps) for 1 minute: 4) $CO_2$ laser treated with 2W mode 6(lOmsec/pulse, 20pps) for 2 minutes: 5) $CO_2$ laser treated with 2W mode 7(20msec/pulse, 20pps) for 1 minute: 6) $CO_2$ laser treated with 2W mode 7(20msec/pulse, 20pps) for 2 minutes. Following the prescribed treatment, the specimens were prepared for SEM evaluation. Results showed that $CO_2$ laser may be effective to occlude dentinal tubules tor dentin sensitivity treatment. The effect of dentinal tubule occlusion was enhanced with increasing the total energy level lased to specimen regardless of lasing mode. The structural changes of root surfaces were restricted to superficies, and these changes included fissuring, charring, crater formation over the smooth lava like texture. The charring and crater formation implying root damage was observed in the case of the longer duration of a pulse. The results of the present study suggests that the pulsed $CO_2$ laser with shorter pulse duration and longer exposure time can be used effectively in order to obtain the optimal dentinal tubule occlusion with minimal root damage.

• Progress in Medical Physics
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• v.16 no.2
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• pp.104-109
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• 2005

Photodynamic therapy (PDT) is one of the expectable current cure operation methods. Tumor tissue is treated by abundant oxygen in a body and generated singlet or free radical from exterior laser diode and photosensitizer. Current problem of PDT is the low penetration power of the light beam in a deep seated large tumor and solid tumor thus results in low treatment outcome. In the study, we tried to develop interstitial photodynamics therapy treatment to solve this problem. As the accurate determination of light dosimetry in biological tissue is one of the most important factors affecting the effectiveness of PDT, parameters used in this study are the optical property of biological tissue. Since biological tissues have large scattering coefficient to visible light the penetration depth of a biological tissue in visible light region is only $15\~20$ mm. We showed that it is possible to measure fluence rate and penetration depth within the biological tissues by Monte Carlo simulation very well. Based on the MC simulation study, the effectiveness of interstitial photodynamic therapy on tumor control in solid tumor was proved through in vivo animal experiment.

• The Journal of the Acoustical Society of Korea
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• v.41 no.5
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• pp.589-600
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• 2022

In order to verify the reliability of Dry Test Bench (DTB) used for testing the output energy from ballistic extracorporeal shock wave therapeutic devices, the measurements with DTB were compared with the acoustic energy measured with a Laser Doppler Vibrometer (LDV) for a commercial ballistic ESWT device. It was shown that the mechanical energy detected with DTB had variability maintained within 5 % at the same output power setting and also had a linear correlation (adj. R² = 0.991) with the acoustic energy measured with the LDV for the entire output power settings. Using the correlation between the two methods and the correlation on the acoustic energy measured in between air and water with the LDV, the DTB measurement can be used to estimate the energy flux density in water with an average error of 7.85 % for the entire output power settings of the ballistic shock wave generator considered in the experiment. DTB provides information limited to the output mechanical energy and therefore it is not suitable for testing the various acoustic output parameters required in IEC61846 and IEC63045. However, DTB that is simple in measurement principles and easy to use is expected for manufacturers and clinical users to monitor the performance of ballistic Extracorporeal Shock Wave Therapy (ESWT) devices.