1.Streptococcus Mutans Biofilm Inhibition Effect of Indocyanine Green and Near Infrared Diode Laser
Yeowon KIM ; Howon PARK ; Juhyun LEE ; Hyunwoo SEO ; Siyoung LEE
Journal of Korean Academy of Pediatric Dentistry 2020;47(4):446-453
The purpose of this study was to evaluate the effect of Indocyanine Green (ICG) and near-infrared (NIR) diode laser on Streptococcus mutans biofilms depending on ICG concentrations.
S. mutans biofilms were formed on a Hydroxyapatite disk, and 0.5, 1.0, 2.0, 3.0, 4.0, 5.0 mg/mL ICG solutions dissolved in sterile distilled water and a NIR diode laser having a power of 300 mW and a wavelength of 808 nm were applied to the biofilms. The temperature changes of the biofilm surface according to the concentrations of the ICG solution were measured using a 1-channel thermocouple thermometer.
Compared to the control group, in the groups with only the 3.0, 4.0, 5.0 mg/mL ICG solution application, and in the groups with the 1.0, 2.0, 3.0, 4.0, 5.0 mg/mL ICG solution application and light irradiation, a statistically significant decrease in the bacterial counts were observed.
The temperature increase according to the concentration of the ICG solutions was 9.53℃, 10.43℃, 11.40℃, 12.10℃, 12.67℃, and 13.63℃ in ICG solutions of 0.5, 1.0, 2.0, 3.0, 4.0, and 5.0 mg/mL respectively.This study presents the potential for clinical application of ICG and NIR diode lasers as a new method for preventing dental caries.
2.Optimal Number of Endoscopic Biopsies in Diagnosis of Advanced Gastric and Colorectal Cancer.
Yeowon CHOI ; Hyo Sun CHOI ; Woo Kyu JEON ; Byung Ik KIM ; Dong Il PARK ; Yong Kyun CHO ; Hong Joo KIM ; Jung Ho PARK ; Chong Il SOHN
Journal of Korean Medical Science 2012;27(1):36-39
Endoscopic biopsy is necessary to confirm a histopathologic diagnosis. Currently, 6 to 8 biopsies are recommended for diagnosis of a suspected malignant lesion. However, multiple biopsies may result in several problems, such as an increased risk of bleeding, procedure prolongation, and increased workload to pathologists. The aim of this study was to clarify the optimal number of endoscopic biopsy specimens required in diagnosis of advanced gastrointestinal cancer. Patients who were diagnosed with advanced gastrointestinal cancer during endoscopy were included. Five specimens were obtained sequentially from viable tissue of the cancer margin. Experienced pathologists evaluated each specimen and provided diagnoses. A total of 91 patients were enrolled. Fifty-nine subjects had advanced gastric cancer, and 32 had advanced colon cancer. Positive diagnosis rates of the first, second, and third advanced gastric cancer specimens were 81.3%, 94.9%, and 98.3%, respectively, while positive diagnosis rates of advanced colon cancer specimens were 78.1%, 87.5%, and 93.8%. Further biopsies did not increase positive diagnosis cumulative rates. This study demonstrated that three specimens were sufficient to make correct pathologic diagnoses in advanced gastrointestinal cancer. Therefore, we recommend 3 or 4 biopsies from viable tissue in advanced gastrointestinal cancer to make a pathologic diagnosis during endoscopy.
Adult
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Aged
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Biopsy/*statistics & numerical data
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Colorectal Neoplasms/*diagnosis/pathology
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*Endoscopy, Digestive System
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Female
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Humans
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Male
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Middle Aged
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Stomach Neoplasms/*diagnosis/pathology