• The Journal of the Korean Society for Microbiology
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• v.17 no.1
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• pp.75-85
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• 1982

In order to demonstrate the effect of specific serum IgG antibody on the adherence of Streptococcus mutans to smooth surface and the mechanism of effective adherence inhibition by IgG antibody, in the present study authors obtained purified IgG from different immunogen preparations of S. mutans NCTC 10449(serotype c) and observed the effect of each IgG preparation on the adherence of each S. mutans strain cultured in different conditions. In addition, the present study was undertaken to observe the cross-reactivity of IgG and the effect of sucrose concentration on the adherence of S. mutans in vitro non-growth condition. The adherence of S. mutans to glass surface was effectively inhibited by serum IgG antibody. At the same IgG concentrations, anti-2% fructose grown/1N NaCl washed S. mutans NCTC 10449 cell showed greater adherence inhibitory effect to S. mutans strains than anti-2% sucrose grown and anti-S. mutans NCTC 10449 cell wall, and the greater inhibitory effects of IgG preparations were observed in assay using 2% fructose grown S. mutans cell preparations than using 0.1% sucrose grown cell preparations. These results suggest that the more effective adherence inhibition by serum IgG antibody is due to the reaction with S. mutans cell surface antigens rather than glucan and cell-associated glucosyltransferase. The greatest adherence inhibitory effect of IgG to S. mutans strains was observed on homologous NCTC 10449 strain and the inhibition cross-reactivities were observed between serotype c, e, and f strains. More pronounced cross-reactivity of adherence inhibition of IgG to S. mutans was observed in assay using anti-2% fructose grown/1N NaCl washed cell than using other IgG preparations, and observed in assay using 2% fructose grown S. mutans cell preparations than 0.1% sucrose grown cell preparations. It was interested that low, but adequate concentration of reactive IgG antibody significantly increased the adherence ability of S. mutans. This result may be due to the formation of small cell aggregates resulted in a increase in the numbers of organisms which adhered to glass surface. The adherence of S. mutans to glass surface was possible in the absence of glucan-synthetic activity. Low level of sucrose significantly increased the adherence ability of S. mutans to glass surface, but excessive amount of sucrose induced large cell aggregates resulted in a decrease in the numbers of organism which adhered.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.4
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• pp.363-368
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• 2000

The purposes of the study was to examine changes in thickness and strength of the rat femur after administration of sodium fluoride in the drinking water. 48 female Sprague-Dawley rats were randomly divided into 4 groups, and they were supplied with 0(control), 1, 5 and 50 ppm of fluoride in the drinking water ad libitum for 6 weeks. Rats were killed and both sides of femur were dissected. Bone strength was measured as the stress of failure of femur at the middle point and femoral neck with Instron. Histologic slides were prepared from the femur shaft with routine processing of fixing, demineralizing, embedding and HE staining. Thickness and area of cortical bone and medullary cavity were measured by using Camera Lucida and Image Analyzer. All the collected data were analyzed with one-way ANOVA, Duncan's multiple range test for post-hoc tests and ANCOVA using the SAS 6.12 package at the level of 0.05. Bone strength increased significantly in the animals given 1 and 5 ppm of fluoride in the water, as compared to the control group. There were significant decreases of stress at fracture in 50 ppmF group compared to the 1 and 5 ppmF groups. The similar trends of bone strength at the femoral neck fracture test, but there were no statistical significances. Cortical bone thickness and area of the femur increased in the 1 and 5 ppmF groups compared to the control. However, the thickness of 50 ppmF group also decreased significantly as compared to 1 and 5 ppmF groups. On the other hand, medullary thickness and area increased in all fluoride groups than control group. All of the findings presented support the conclusion that, low fluoride dosage used in water fluoridation could increase the bone strength and might have preventive effect on femur fracture.

• Journal of dental hygiene science
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• v.14 no.2
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• pp.123-131
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• 2014

Environmental tobacco smoke (ETS) or second hand smoke or passive smoking has become a well-known risk factor for various health hazards in nonsmoking adults as well as active smokers. In Korea, there have been few studies concerning about the impact of ETS on periodontal health. Therefore, the aim of this study was to investigate the association between exposure to passive smoking and prevalence of periodontitis using Korea National Health and Nutrition Examination Survey (KNHANES) in 2008 and 2009. The Fourth KNHANES data was employed from 2008~2009. The final sample size was 4,669 adults aged over 18 years, who were never-smoker and had the information about ETS both at home and in the workplace, urine analysis and periodontal examination by Community Periodontal Index (CPI). Periodontitis was defined as CPI codes ${\geq}3$. Data were analyzed using PASW Statistics 18.0. The sociodemographic and behavioral factors were adjusted as confounders. Overall, 17.1% (male 16.4%, female 83.6%) of the participants were exposed to ETS. The mean concentration of cotinine in those exposed ETS was significantly higher than that in unexposed people ($46.92{\mu}g/ml$ versus $19.34{\mu}g/ml$, p<0.001). Participants exposed to ETS were more likely to have periodontitis than those unexposed after adjusting for potential confounding variables. ETS is associated with the prevalence of periodontitis in Korean adults. This may suggest that patients with periodontitis or periodontal surgery should be protected from smokers or smoking places.

• Journal of Dental Rehabilitation and Applied Science
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• v.33 no.1
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• pp.7-18
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• 2017

Purpose: Nonsteroidal anti-inflammatory drugs that prohibit biosynthesis of arachidonic acid metabolites have been considered potent host modulation agents. The aim of this review was to determine the effect of nonsteroidal anti-inflammatory drugs adjunctive with nonsurgical periodontal treatment in patients with periodontal disease. Materials and Methods: Three electronic databases were searched to identify relevant studies. The methodological quality and mean differences of the change in clinical attachment level and probing depth were analyzed according to Cochrane review methods. Results: Twelve studies were included in the methodological assessment and nine studies were suitable for inclusion in the meta-analysis. The mean difference in the clinical attachment level gain did not differ significantly between the nonsteroidal anti-inflammatory drugs and control groups at any observation time. The highest mean difference in clinical attachment level gain was 0.30 mm at 4 weeks (95% confidence interval = -0.37 to 0.97). There was a significant mean difference in the probing depth reduction, of 0.34 mm (95% confidence interval = 0.29 to 0.40) at 6 weeks. Conclusion: Therefore, nonsteroidal anti-inflammatory drugs have additional therapeutic effect when administrated with nonsurgical periodontal treatment.

• Journal of dental hygiene science
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• v.11 no.5
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• pp.411-416
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• 2011

Streptococcus mutans (S. mutans) is the major causative bacteria in dental caries. Xylitol is effective anticarious natural sugar substitute by inhibiting the virulence of S. mutans. However, long-term xylitol consumption leads to the emergence of the xylitol-resistant (XR) strains which means xylitol is no more inhibited their growth. We therefore confirmed the general characteristics and the virulence factors of the xylitol-sensitive (XS) and XR S. mutans for different concentrations of xylitol. S. mutans KCTC 3065 was maintained in TYE medium containing 0.4% glucose with 1% xylitol during 30 days at $37^{\circ}C$, 10% $CO_2$ to form XR strain. The strains were transferred to new medium every 24 hr and the same procedures without xylitol were repeated for the formation of XS S. mutans. Both XS and XR were cultured in different concentrations of xylitol (0%, 0.1% and 1%) then, cell growth, acid production and mRNA expression of gtf genes were analyzed. Xylitol reduced the cell growth of XS S. mutans in dose-dependent manner, but not reduced that of XR. Xylitol inhibited acid production of XS in dose-dependent manner, but not inhibited that of XR. Xylitol reduced the gtfB and gtfD mRNA expression of XS S. mutans which genes synthesized soluble and insoluble extracellular polysaccharides, but not reduced that of XR. These results indicate that the virulence of XR S. mutans is different characters of XS strains, which suggests XR strains may have different cariogenicity of XS strains. Further study is needed to explain the mechanism related to extracellular polysaccharide in the XR strains.

• Journal of dental hygiene science
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• v.10 no.3
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• pp.141-146
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• 2010

The purpose of this study was to survey the knowledge of parents, to prepare basic data for the development of adjusted water fluoridation program. The survey with self-administrated questionnaire was carried out to n 1,418 parents of school-children in Kimje city and then analyzed obtained the results. The data were analysed using the chisquare test. Over all, 58.4 percent of parents has heard about adjusted water fluoridation. 50.1% respondents knew very well the object of water fluoridation program which is implemented to prevent dental caries. The recognition rate of water fluoridation were different according to respondent's education level(p=.000) and income(p=.019). The approval rate of water fluoridation were different according to respondent's education level age level and income(p<.001). The parents had the affirmative opinion for the adjusted water fluoridation was 4.5 times more than the negative opinion. Respondents approving and opposing for the implementation of water fluoridation were 82.3% and 17.7%, respectively. The recognition rate and approval rate of water fluoridation had the affirmative opinion for the adjusted water fluoridation was more than the negative opinion. Respondents approving and opposing for the implementation of water fluoridation were 85.5% and 14.2%, respectively. The parents of school children had affirmative opinion to the adjusted water fluoridation. So for implementation of the water fluoridation, it is required to reinforce education for inhabitants through delivery of right information and various publicity activities.

• Journal of Korean society of Dental Hygiene
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• v.14 no.1
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• pp.101-108
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• 2014

Objectives : The purpose of this study was to evaluate the tooth whitening effect of 0.74% and 2.80% hydrogen peroxide toothpastes and safety on tooth and gingival tissue. Methods : Toothpastes containing 0.74% and 2.80% hydrogen peroxide were evaluated. In in-vitro test, some additives (sodium metaphosphate, sodium pyrophosphate and titanium dioxide) were added to the toothpastes. Hydroxyapatite specimens (HAPs) were made and stained using modified Stookey's methods. HAPs were treated for 1 hour at shaking incubator and brushed for 1,000 times as 250 gF with each diluted toothpaste. Before and after color was measured by colorimeter. Using double blind method, 99 Korean with natural maxillary anterior teeth were selected and the initial brightness (baseline) was measured by SHADEEYE-EX. Based on this measurement they were crossly distributed into control group (0% hydrogen peroxide), test 1 (0.74% hydrogen peroxide) and test 2 (2.80% hydrogen peroxide). After 2 weeks, people of each group were provided toothpaste and told to use 3 times a day right after every meal for 3 minutes. The brightness of teeth was measured 3 times for every one month. Results : ${\Delta}L$ was statistically significant among three groups in shaking test. ${\Delta}L$ of two test groups was statistically significant compared with control group but not between each test group in brushing test. After using toothpaste for 3 months, test 1 group and test 2 group were 15.89% and 31.23% more whitened compared with control group respectively (p<0.05). Rate of more whitened person of each test group was 24.2% and 40.5% more than control group respectively (p<0.05). There was no difference in the hypersensitivity during 3 months using toothpastes and no side effect on teeth or gums. Conclusions : Toothpastes containing 0.74% and 2.80% hydrogen peroxide showed tooth whitening effect and both were safe enough to use for tooth whitening.

• Journal of dental hygiene science
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• v.7 no.3
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• pp.197-200
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• 2007

This study was carried out to assess anticariogenic activity from natural products. The hexane extracts of 11 medicinal plants were tested for the antimicrobial activities against a cariogenic bacterium, S. sobrinus B13. The hexane extracts of 11 medicinal plants such as Alisma orientale, Cyperus rotundus, Saussurea lappa, Atractylodes japonica, Kalopanax pictus, Angelica gigas, Salvia miltorrhiza, Lonicera japonica, Gardenia jasmoides, Aurantii nobilis percarpium and Bupleurum lorgiradiatum were used for this study, and S. sobrinus B13 was cultured with 0.5% extracts of the medicinal plants, in trypticase soy broth medium under 5% $CO_2$ for 0, 6, 12, 24 hours at $37^{\circ}C$. The obtained results were as follows. Immediately after culturing for inoculation, Kalopanax pictus and Cyperus rotundus showed better antimicrobial activities than those of others. After culturing for 6 hours, the order of effective antimicrobial activity was Salvia miltorrhiza, Angelica gigas. After incubation for 12 hours, Salvia miltorrhiza showed the best antimicrobial activity. After incubation for 24 hours Salvia miltorrhiza, Cyperus rotundus, Saussurea lappa, Atractylodes japonica had better antimicrobial activity than others. In conclusion, among Hexane extracts of 11 medicinal plants, Cyperus rotundus, Saussurea lappa, Atractylodes japonica showed effective antimicrobial activity.

• Journal of dental hygiene science
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• v.18 no.2
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• pp.105-112
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• 2018

The purpose of this study was to focus on the number of brushing strokes among the performance factors and identify if the 10 times stroke of the rolling method is rational. Moreover, we evaluated the changes in oral health knowledge, perception, and behavior after our rolling method instruction. The 10-stroke method of toothbrushing has been regarded as an effective method of removal of dental plaque, although there is little evidence to support this claim. We allocated 40 healthy subjects to two intervention groups. During five visits, we measured a score for dental plaque removal and instructed the subjects on a toothbrushing technique with 5 or 10 strokes per section. At the initial and final visits, subjects completed a questionnaire on one designed specifically for this study about oral health knowledge, perceptions, and behaviors. Repeated measures analysis of variance was used to compare the dental plaque removal score between the groups, and the changes in scores within each group over time. We also compared changes in mean scores in oral health knowledge, perceptions and behaviors before and after toothbrushing instruction. We found that the score for dental plaque removal increased with each additional toothbrushing instruction in both groups (p<0.001). However, we found no differences in the dental plaque removal scores between the 5-stroke and 10-stroke groups (p=0.399). The levels of oral health knowledge, perceptions and behaviors increased after the toothbrushing instructions in both groups. Our findings suggest that there is no advantage in emphasizing the 10-stroke method of toothbrushing in an oral health education program.

• Journal of dental hygiene science
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• v.15 no.3
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• pp.340-347
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• 2015

The purpose of this study is to analyze the factors of oral function associated with number of present teeth (NT) in Korean elderly adults. The research was designed as cross-sectional study using the data of the 4th Korea National Health and Nutritional Examination Survey, and the samples were selected by stratified clusters sampling. The subjects aged 55 to 84 years were 4,780 that joined the oral examination survey and questionnaires. The respective variables reflecting socioeconomic status, subjective health status and oral function factor were analyzed and their distributional differences were confirmed by complex sampling logistic regression analysis. Multivariable liner regression models considering covariates were applied to explain the associations between the number of present teeth and other variables. Gender, educated level, illegal dental treatment, self-rated oral health and oral functional factors, including chewing behavior and speaking behavior, were associated with the number of present teeth (p<0.05). Subjects with better self-rated oral health had more NT than those with worse. Subjects with worse speaking behaviors had less NT than those with better. Interventions aiming to enhance oral health in elderly adults should consider socioeconomic, demographic, and oral functional factors.