• The korean journal of orthodontics
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• v.27 no.6 s.65
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• pp.979-995
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• 1997

The purpose of this study was to identify the preventive and the progressive inhibitory effects of enamel demineralization with fluoride releasing light-and self-cured orthodontic sealants(FluoroBond), in vitro, under the polarizing light microscope and the scanning electon microscope. The polarizing light microscopic group was subdivided into seven groups(Group A-Group G). The scanning electron microscopic group was also subdivided into seven groups(Group A'-Goup G'). For polarizing light microscopic evaluation, longitudinal sections were made longitudinally by Maruto cutter(Maruto Co., Japan) and Maruto grinding machine(Maruto Co., Japan). Sections were examined and photographed by the polarizing light microscope(Olympus Optical Co., Japan) using crossed polars and with the enamel rod longitudinal axis oriented at $45^{\circ}$ to the extinction position. For scanning electron microscopic evaluation, the specimens were coated with a highly conducting layer of gold palladium in a model Hus-4 high-vacuum evaporator and examined in an ISI-100B scanning electron microcope operated at 20kV. The results of this study were as follows : 1. The mean depths of artificial carious lesions under a polarized light microscope were $Group\;A(5.08{\mu}m),\;Group\;B(47.82{\mu}m,\;Group\;C(8.42{\mu}m),\;Group\;D(7.20{\mu}m),\;Group\;E(85.41{\mu}m),\;Group\;F(60.38{\mu}m),\;Group\;G(60.13{\mu}m)$. 2. There were statistically significant differences in Group B compared with Group A, C, and D(p<0.05), and also, in Group I compared with Group F and Group G(p<0.05). 3. Light-and self-cured orthodontic sealants had the preventive effects of enamel demineralization. 4. Light-and self-cured orthodontic sealants had the progressive inhibitory effects of enamel demineralization. 5. The time progress of demineralizing agent had no influence on the samples of light-and self-cured orthodontic sealants under the scanning electron microscope. 6. There was no difference between the specimens of light-and self-cured orthodontic sealants both in the polarized light microscopic group and in the scanning electron microscopic group.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.753-759
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• 2001

To evaluate antiinflammation of Aloe vera peel, antiimflammation substances were extracted from Aloe vera peel and identified, and we investigated the effect of the its substance the inhibitory effect on the activity of hyaluoronidase, elastase, collagenase and prostaglandin endoperoxide synthase. The water extract from Aloe vera peel were successfully purified with solvent fractionation, silica gel column chromatography, preparative thin layer chromatography and UV spectrometer. Two purified active substances were identified as aloe-emodin and barbaloin by Mass Spectrometer, $^1H-NMR$ and FT-IR. Aloe-emodin and barbaloin. $IC_{50}$ values of aloe-emodin and barbaloin against hyaluronidase activity were 40 and $70\;{\mu}g/mL$, respectively. Leuckocyte elastase, which is related to the destruction of various tissue, $IC_{50}$ values of them were 50 and $60\;{\mu}g/mL$, respectively. $IC_{50}$ values of aloe-emodin and barbaloin against collagenase activity were 40 and $60\;{\mu}g/mL$, respectively. and $IC_{50}$ values of aloe-emodin and barbaloin aganist the prostaglandin endoperoxide synthase, which play an important role in inflammatory reactions, were 40 and $70\;{\mu}g/mL$, respectively. Inhibitory effects of aloe-emodin, barbaloin and aspirin against carrageenan paw edema were 74.9, 52.9 and 51.9% as inhibiton percentage, respectively, at dose of 100 mg/kg and that of indomethancin was 49.7 at dose of 10 mg/kg. Cell cytotoxicity of barbaloin against human gingival cells was lower than that of aloe-emodin. Aloe-emodin and barbaloin did not show cytotoxicity against human gingival cells at concentration of 1.0 and $5.0\;{\mu}g/mL$, However, aloe-emodin and barbaloin showed less cytotoxicity than chlorhexidine, which usually have been used as the agent of anticaries and antiinflammation. These results suggested that aloe-emodin and barbaloin from Aloe vera peel have the effect of anticaries and antiinflammation.

• Journal of Dental Rehabilitation and Applied Science
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• v.31 no.2
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• pp.150-157
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• 2015

The purpose of this report is to suggest clinical managements of implant periapical lesions by presenting three clinical cases managed by either the infected form or the inactive form with the follow-up period of five to twelve years. One patient with no clinical symptom was regarded as inactive form. Two patients having pain were regarded as infected form and have been under the systemic antibiotic therapy. In one patient, the symptom subsided and the size of radiolucent lesion decreased. However, the other patient showed increased size of lesion causing the implant unstable, which leaded to remove the implant and to replace it. There was neither additional increase of the lesion nor functional problem for all three. It is important to detect implant periapical lesion in early stage before jeopardizing the stable implant and manage properly using systemic antibiotic therapy and surgical approach if needed, depending on infected form and inactive form.

• Journal of the korean academy of Pediatric Dentistry
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• v.48 no.3
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• pp.324-332
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• 2021

This study was conducted to investigate changes in dental visits in children and adolescents due to COVID-19. Based on the data provided by the Korea Health Insurance Review and Assessment Service, the number of dental visits among children and adolescents from January 2019 to August 2020, and the rate change according to Korean disease classification in 2019 and 2020 were analyzed by month and region. From January to August 2020, compared to the same period in 2019, the total number of visits to dental clinics and dental hospitals among children and adolescents decreased by 642,202 times (16.3%) in the 0 - 9 years old group, and 313,488 times (9.2%) in the 10 - 19 years old group. During the same period, the decreases due to Z29 (Need for other prophylactic measures) decreased by 118,219 times (34%) in the 0 - 9 years old group and 83,944 times (31%) in the 10 - 19 years old group, showing the greatest change. It is analyzed that overall dental service of children and adolescents has decreased due to COVID-19, and this may lead to deterioration of oral health of children and adolescents in the future, and this study can be used as a reference in case of an infectious disease such as COVID-19 in the future.

• Journal of Oral Medicine and Pain
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• v.38 no.3
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• pp.275-289
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• 2013

This study was conducted to investigate and analyze the dental patients' awareness and understanding about TMDs. Among the total number of 243 patients who had visited the department of dentistry of Busan Paik Hospital, Inje University or Hanvit dental hospital in Ulsan metropolitan city and participated in the survey, 195 patients who filled in all parts of the questionnaire were selected as the subjects. The results were as follows. 1. The subjects who were aware of the term, "TMDs" were 17.4%. The group with total education period of 12 years and over was significantly more aware of "TMD"(82.4%, p<0.01) than the other group. The subjects who were aware of the term, "jaw joint disease" were 81.0%. 30 to 49 age group(45.6%, p<0.05) and the group with total education period of 12 years and over(60.1%, p<0.01) were significantly more aware of "jaw joint disease" than other groups. 2. More than half of the subjects chose "overuse of the jaws" as the concept of jaw joint disease(50.6%). 3. TV, radio(41.4%) was the most frequent source of awareness about jaw joint disease followed by family and friends(20.2%), hospitals and health professionals(18.2%), internet(15.7%) and newspapers, magazines(4.5%). Among the respondents who were aware of jaw joint disease through TV, radio, 30 to 49 age group showed significantly higher percentage(52.4%, p<0.05) than other age groups. Among the respondents who were aware of jaw joint disease through internet, 18 to 29 age group showed significantly higher percentage(61.3%, p<0.01) than other age groups. Among the respondents who were aware of jaw joint disease from hospitals and health professionals, the group with total education period of 12 years and over showed significantly higher percentage(75.0%, p<0.05) than the other group. 4. Noise during mouth opening and closing(26.9%), mouth opening difficulty(25.1%) and jaw pain(13.7%) were the most frequently responded sign and symptoms of jaw joint disease. For the causes of jaw joint disease, enjoying hard food chewing(19.5%), occlusal discrepancy(19.0%) and chewing with one side only(18.5%) were responded in sequence. TMJ surgery(28%) was the most frequently responded treatment method for jaw joint disease, followed by occlusal appliance therapy(23.9%) and physical therapy(14.6%). For preventive method of jaw joint disease, avoid eating hard food(21.1%), avoid opening mouth wide(17.0%) and simultaneous using of molar of both side when chewing food(15.4%) were chosen frequently.

• Journal of dental hygiene science
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• v.8 no.4
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• pp.313-322
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• 2008

The purpose of this study was to examine the awareness of dental hygienists in different regions about credit bank system and their needs for that. The subjects in this study were 312 dental hygienists in dental hospitals and clinics in Seoul, Gyeonggi province, metropolitan cities, Gangweon province and Gyeongsang province. After a survey was conducted in 2008, the collected data were analyzed with SPSS 11.5 program. The findings of the study were as follows: 1. In regard to perception of the credit bank system, 68.3 percent of the dental hygienists were cognizant of that. The dental hygienists from most of the geographic areas were aware of it, but all the forty three dental hygienists from Gangweon province who accounted for 13.8 percent didn't know about that. As for media by which they acquired information on that, many of the dental hygienists learned about it from their acquaintances (46.2%), but that was not the case for the dental hygienists from Seoul and Gyeonggi province. 2. As for expectations for the credit bank system, those from Gyeongsang province had the greatest expectations for that in six out of nine items, which included academic or job performance improvement, acquisition of credits, degree or certificates and access to new technology. 3. Concerning educational spending on the credit bank system, 18.9 percent and 8.7 percent from Seoul/Gyeonggi province and Gangweon province spent less than 30 thousand won, and 19.9 percent from the metropolitan cities spent 30 thousand to less than 50 thousand won. 4. As for the importance of the categories of their major in the credit bank system, those from Gangweon province attached the most importance to oral health education ($3.56{\pm}1.259$), and the dental hygienists from the metropolitan cities put the most stress on preventive treatment ($3.64{\pm}1.191$).