• The Journal of Korean Academy of Prosthodontics
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• v.39 no.2
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• pp.208-219
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• 2001

To study the effect of dentin permeability on a tooth with wear from tooth brushing after application of desensitizing agent, extracted teeth free from caries were chosen. Coronal dentin discs with thickness of 1mm were prepared. Using the split chamber device developed by Pashely, hydraulic conductance, scanning electron microscope images(SEM) and atomic force microscope images(AFM) were compared and contrasted before and immediately after the application of desensitizing agent and after equivalent tooth brushing of 1 week, 2 weeks, and 6 weeks. Four commercially available desensitizing agents were used in this study ; they were Gluma, Seal & Protect, All-Bond 2 and MS Coat. The results of this study are as follows. 1. On all specimens, the hydraulic conductance decreased after the application of tooth desensitizing agent. 2. Except the specimens treated with MS Coat, the remaining specimens had an increase in dentin permeability after tooth brushing for 1 and 2 weeks but a decrease after 6 weeks. 3. The specimens treated with MS Coat had statistically significant increase in the dentin permeability regardless with the duration of tooth brushing. 4. On examination of SEM and AFM, the dentinal tubule diameter had decreased after treatment of desensitizing agents. The specimens other than those treated with MS Coat, smear layers were noted after tooth brushing. It is not always consistant but the hydraulic conductance correlated with the images from SEM and AFM.

• Journal of Periodontal and Implant Science
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• v.41 no.3
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• pp.131-134
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• 2011

Purpose: To test the plaque-removal efficacy of a single-tufted toothbrush on the posterior molars compared with a flat-trimmed toothbrush. Methods: Forty-nine subjects were selected. Professional instruction and written brushing instructions were given. After thorough supra-gingival scaling and polishing, all subjects were asked to abstain from oral hygiene procedures for 24 hours prior to the first experiment. The subjects were randomized to a treatment sequence. The modified Quigley and Hein plaque index was recorded pre- and post-tooth brushing, at 6 surfaces of the posterior molars. After a wash-out period, all the remaining plaque was removed professionally. Twenty-four hours of brushing abstinence was again performed. The plaque index was recorded pre- and post-tooth brushing after the subjects were given the second toothbrush in the cross-over sequence. Results: The percentage reductions in plaque scores achieved with the single-tufted brushes were significantly higher than those of the flat-trimmed brush at the maxillary buccal interproximal, marginal and mandibular lingual interproximal site. The other locations showed no significant difference. Conclusions: The results of the present study implied that the single-tufted brush could be an effective tool for the removal of plaque at some, but not all, sites of the posterior molars.

• Journal of Periodontal and Implant Science
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• v.43 no.6
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• pp.301-307
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• 2013

Purpose: This in vitro study was performed to assess the adherence of Porphyromonas gingivalis to a resorbable blast media (RBM) titanium surface pretreated with an ultrasonic scaler or toothbrush and to evaluate the effects of the treatment of the RBM titanium discs on the bacterial removal efficiency of brushing by crystal violet assay and scanning electron microscopy. Methods: RBM titanium discs were pretreated with one of several ultrasonic scaler tips or cleaned with a toothbrush. Then the titanium discs were incubated with P. gingivalis and the quantity of adherent bacteria was compared. The disc surfaces incubated with bacteria were brushed with a toothbrush with dentifrice. Bacteria remaining on the disc surfaces were quantified. Results: A change in morphology of the surface of the RBM titanium discs after different treatments was noted. There were no significant differences in the adherence of bacteria on the pretreated discs according to the treatment modality. Pretreatment with various instruments did not produce significant differences in the bacterial removal efficiency of brushing with dentifrice. Conclusions: Within the limits of this study, various types of mechanical instrumentation were shown to cause mechanical changes on the RBM titanium surface but did not show a significant influence on the adherence of bacteria and removal efficiency of brushing.

• The Journal of Korean Academic Society of Nursing Education
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• v.7 no.2
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• pp.229-244
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• 2001

The purposes of this study are to do surveys of the state of health and dental health behaviors of higher grade students in elementary school and their mothers, to investigate the relationship of students' dental health, and to apply those results to the systematic and efficient dental health care. The subjects were totally 618 people, including 309 elementary school students in 4th, 5th, or 6th grades and their mothers in Pusan. The questionnaires were used as instruments, which were made by the researcher and related with other preceeding studies. The content validity of the instruments was tested by two professors of nursing. Dental checking were conducted by an expert of dental sanitation, according to the standard of the World Health Organization. The period of collecting data was 20 months from October 20th to December 20th in 2000 and the collected data were analyzed by SAS program and classified as the real number, the percentage, the mean, the standard deviation, t-test, and F-test. In conclusion, there is no significant correlation between grades and treated or treatment-needed permanent teeth. There is the highest significant correlation between treated or treatment-needed permanent teeth and students' dental health behaviors. There is high significant correlation between mothers' dental health behaviors and students' dental health behaviors. Also, There is significant correlation between mothers' state of dental health and students' state of dental health. From the results of this study, the students' dental health behaviors are the most important variables in the students' state of dental health. But both boys(9.48) and girls(9.97) get the low marks on the total mark 15 about brushing, which can be self-controlled. Therefore, the developments of dental health guidance in education about dental health by mothers or the educational courses in schools, such as brushing educations by the experts, dental health education, brushing after lunch, or the various equipments in brushing, should be accomplished. Above all, behavior-centered education should be conducted instead of knowledge-centered education.

• Journal of the Korean Wood Science and Technology
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• v.35 no.3
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• pp.70-78
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• 2007

This study explored the efficient dyeing method of aged chestnut wood using the natural dyes extracted from Gardenia jasminoides for, grandiflora, Carthamus tinctorius L., Rhus javanica L., Lithospermum erythrorhizon S. et Z., Caesalpinia sappan L. and Castanea crenata S. et Z.. The color variation of the dyed chestnut woods was also quantitatively evaluated. The wood specimens revealed abundant colors through different dyeing conditions such as dyeing temperature, dye pH, soaking time, and brushing frequency. The chroma and stain concentration of colored woods were calculated with $L^*$, $a^*$ and $b^*$ in order to make color tone measurement. Brushing treatment for colored wood was confirmed as a more economical dyeing method than soaking treatment requiring more time when natural dyeing was done. Furthermore, the desirable tone and shade of color was easily obtained by repetitive brushing treatment using low color tone. During natural dyeing, good color expression was made with high temperature and acidic condition of a dyeing liquor.

• Journal of Korean society of Dental Hygiene
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• v.11 no.5
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• pp.695-706
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• 2011

Objectives : The purpose of this study is to assess oral health perception, oral health behavioral and family smoking status according to smoking experience in a part of high school students. Methods : A survey is conducted with a total of 648 first grader at high school in Dae-Gu city from 1st to 30th September, 2009. The results are as follows. Results : 1. 95.5% of respondents are 'smoking is very harmful for health' and the majority of smoking-related disease are lung cancer, oral disease, and oral cancer. 2. 127 respondents have experience in smoking and 62 respondents are smoking at that time. 59.7% respondents have 1 year smoking history and the majority of respondent are 5 cigarettes/day. 67.8% respondents are under 5 cigarettes/day. 3. In oral health behavioral by smoking, the majority of smokers' teeth brushing are 3 times, 47.2% and 2 times, 27.6%. The majority of nonsmoker's teeth brushing are 3 times, 47.0% and 2 times 26.5%. The results of teeth brushing time are significantly different between smokers and non-smokers(p<.001). The majority of smokers and non-smokers have not experienced about scaling. It is significantly different between 2 groups(p<.05). 4. The smoking rate of father and grandfather in smokers is higher than non-smokers. It is significantly different between 2 groups(p<.005). 5. The need for oral management in oral health education is gum treatment and dental caries treatment. 22.8% smokers and 25.7% non-smokers require to get gum treatment. 18.1% smokers and 20.2% non-smokers required to get dental caries treatment. Conclusions : Also Future longitudinal research is required to develop oral health promotion program contents according smoking-oral health.

• Corrosion Science and Technology
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• v.8 no.6
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• pp.209-216
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• 2009

In this study the effect of different surface finishing techniques on the pitting corrosion behaviour of a commercial 304 stainless steel alloy was investigated. Surface finishing methods were divided into two categories, i.e. mechanical and chemical. Mechanical treatment methods include power tooling such as grinding, emery paper brushing, stainless steel wire brushing and stainless steel shot blasting. Chemical treatment methods include chemical passivation (phosphoric acid, citric acid, nitric acid) and electro-cleaning (phosphoric acid and citric acid). Potentiodynamic polarization experiments were carried out in 3.5 wt. % NaCl solution at room temp. (20 $^{\circ}C$). The results showed that chemical treatment methods improved the corrosion resistance of stainless steel 304, measured in terms of pitting potential ($E_{pit}$). Corrosion resistance of the specimens was increased in the order of; electro-cleaning > manual passivation > mechanical cleaning. Surface of electro-cleaned specimens was smoother than rest of the surface treatment methods. Chrome content in chemically treated specimens was higher than in mechanically treated specimens as shown by EDX analysis.

• Korean Journal of Health Education and Promotion
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• v.20 no.2
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• pp.95-112
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• 2003

Objectives： Oral health care program for the elementary school children (ESOHCP) should be met the first priority because dental caries are highly sensitive and prevalent among them. This study was performed to enhance the efficiency of ESOHCP, and their oral health promotion. Methods： The Subjects were 346 students (3rd grade 163, 6th grade 185) of one elementary school in Busan. Dental IQ and actual oral health status； the decayed, mixing and filling teeth were checked through questionnaire and oral health examination from April to June 2002. Dental IQ was presented out of one hundred, and data analysis was done using SAS (ver 8.1) program. Results： The students' cognitive level about the causative and preventive factor of dental caries was relatively high. However, the practical aspects of preventive behavior - tooth brushing； three times per day (20％), three minutes per time (22％), oral health examination； one time per three months (10％) left much to be desired. And, only 27％ of the subjects had experienced in school oral health education. The mean level of dental IQ was 79 out of 100, and 51 ％ and 42％ of them had the decayed and teeth with filling, respectively, with the rate of DMFT 82％, DT 43％, FT 57％. The level of dental IQ was higher in case of having his (her) own tooth brush (p＝0.072), standard tooth brushing (p<0.001) three times per day, post meal, three minutes per time, present experience of oral health examination (p<0.001) and dental clinic visit (p<0.001). The grade of caries was more serious in case of 6th grade (p＝0.059), an absence of his (her) own tooth brush (p＝ 0.090), present experience of oral health examination (p＝0.021), and an absence of regular dental clinic visit (p＝0.003). The frequency of oral health examination (γ＝ 0.620), tooth brushing； times per day (γ＝0.445), post meal (γ＝0.355), expending times per brushing (γ＝0.352), right cognition to the treatment of caries (γ＝0.401), positive attitude to dental treatment (γ＝0.387), the frequency of dental clinic visit for the past one year (γ＝0.152) showed significant correlation with dental IQ. In the multivariate analysis, dental IQ was influenced by the frequency of oral health examination, right cognition to the cause of caries, times of teeth brushing per day, right cognition to the treatment of caries, etc., with adjusted R2＝0.857. Conclusion： Though the students' cognitive level about the causative and preventive factor of dental caries was high, the practical aspects of preventive behavior left much to be desired. Ant the current ESOHCP considered to be still inefficient. However, frequent dental visits had apparent correlation with hish level of dental IQ. The specialized and practical program should be needed for the efficient ESOHCP. Harmonized effort from educational, health and dental society is essential.

• Journal of dental hygiene science
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• v.23 no.3
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• pp.236-244
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• 2023

Background: The size of the tooth whitening market and toothpaste market is increasing worldwide. The purpose of this in vitro study is to confirm and compare the coffee stain removal effects of commercial whitening toothpaste in sound and demineralized teeth, respectively. Methods: A total of 112 flat permanent bovine teeth specimens were manufactured. Half of the surface of the specimen was coated with an acid-resistant varnish and deposited in an artificial demineralizing solution for 65 hours. The varnish applied to half of the specimen was removed and deposited in a coffee solution for 96 hours to induce coloring. Two control and five experimental group toothpastes for teeth whitening were selected and the main components were investigated. Toothbrushing was performed 50, 100, and 150 times for each toothpaste group. A total of four images were obtained: before the start and after 50, 100, and 150 times of brushing to obtain the lightness (L^*) values of the sound and the demineralized tooth surfaces. The difference in the average value between toothpaste groups at each treatment period was analyzed by one-way ANOVA. The difference in the L^* average value according to the number of the brushing was analyzed by repeated measure ANOVA. Results: All toothpastes in the seven groups contained abrasive agents and had different ingredients for each product. Compared to before brushing, the L^* value changed significantly in all toothpaste groups after brushing 50 times (p<0.05). This was common in both the sound and demineralized teeth surfaces. Demineralized teeth had significantly lower L^* values at all brushing times than that in sound teeth (p<0.05). Conclusion: The effect of whitening teeth was different for each toothpaste. Demineralized teeth were more likely to cause coloration than sound teeth, and the coloration was not removed well.

• The korean journal of orthodontics
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• v.34 no.2 s.103
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• pp.189-195
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• 2004

The purpose of this research is to evaluate and compare the plaque removal ability of sonic brushing and manual brushing in order to present a method for continuous and effective oral hygiene control during orthodontic treatment. Nonextracted adolescent patients (male: 23 persons, female: 37 persons) and adult patients (male: 15 persons, female: 45 persons) outfitted with a fixed orthodontic appliance from their incisors to second molar, in both the maxilla and mandible, were divided into manual brushing and sonic brushing groups. A Philips oral healthcare HX-4401 sonic toothbrush was used, and the application of brushing for the two groups was standardized at two minutes. After brushing, the plaque score was measured with a modified Wilkin's PHP. The following results were achieved after comparing each group's plaque score. 1. In patients with a fixed orthodontic appliance when age was not accounted for, the application of sonic brushing exerted a beneficially decreased effect on the plaque score. (adolescents : p<0.01, adults: p<0.05) 2. When comparing the adolescent and adult groups in regard to plaque score, the adolescent group showed a more decreased effect. 3. When using the same toothbrush type, there was no difference between the adolescent and adult groups.