No abstract available.

OBJECTIVES: The purpose of this study was to compare the oral antimicrobial effects of seven different mouthwashes available in Korea. METHODS: To examine the antimicrobial effects of the seven mouthwashes, their minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were determined using broth microdilution methods. Streptococcus mutans ATCC 25175, Lactobacillus acidophilus ATCC 4355, Candida albicans KCTC 7270, and Porphyromonas gingivalis ATCC 33277 were used in this experiment. S. mutans and P. gingivalis were examined using a scanning electron microscope (SEM), after treatment with the mouthwashes containing cetylpyridinium chloride (CPC). RESULTS: Mouthwashes containing CPC had lower MIC and MBC values against the four microorganisms. Their bactericidal effects were concentration-dependent. S. mutans and C. albicans were highly sensitive to the concentration of CPC in the mouthwashes. According to the SEM observation, the treatment of bacteria with mouthwashes containing CPC, changed the cell surface texture of S. mutans and P. gingivalis. CONCLUSIONS: Mouthwashes containing CPC showed relatively lower MIC and MBC values under the same conditions against the four microorganisms used in this study.
Bacteria ; Candida albicans ; Cetylpyridinium ; In Vitro Techniques* ; Korea* ; Lactobacillus acidophilus ; Mouthwashes* ; Porphyromonas gingivalis ; Streptococcus mutans

OBJECTIVES: The purpose of this study was to provide photodynamic bactericidal effect against Enterococcus faecalis by erythrosine concentrations and LED irradiation times. METHODS: Erythrosine was used as a photosensitizer and green LED (3 Watt, 520-530 nm) was used as light source. E. faecalis ATCC 1943 and E. faecalis ATCC 29212 were used in this study. Approximately 10(5) CFU of bacteria were added in wells of a 96-well microtitration plate. For examining the effects of concentrations of erythrosine, 0, 0.625, 1.25, 2.5, 5, and 10 microM of erythrosine were added in wells containing bacteria. The irradiation time with LED was 30 sec. In another set of experiment, the effect of irradiation time for killing of bacteria was investigated by increasing irradiation time from 0 to 30 s with 10 microM of erythrosine final concentration. After irradiation, each sample was serially diluted with PBS and 50 microl of diluents was spread on duplicate blood agar plates. The plates were incubated for 72 h at 37degrees C under aerobic conditions and the number of CFU was determined. The experiments were repeated four times. The results were analyzed using one-way ANOVA, and Tukey's multiple comparison at a significance level of 0.05. RESULTS: When the erythrosine concentrations were more than 2.5 microM, E. faecalis ATCC 29212 was significantly decreased (P<0.05). The more erythrosine concentrations increased, the more E. faecalis ATCC 1943 decreased statistically significantly (P<0.05). In another set of experiment, when LED irradiation time was more than 20 s, E. faecalis ATCC 1943 decreased significantly (P<0.05), and if the irradiation times was more than 5 s, E. faecalis ATCC 29212 decreased significantly (P<0.05). CONCLUSIONS: PDT using erythrosine and green LED was found to be an effective method in killing E. faecalis.
Agar ; Bacteria ; Enterococcus faecalis* ; Erythrosine* ; Homicide ; Photochemotherapy

OBJECTIVES: The purpose of this study was to evaluate abrasion of Icon(R) infiltrated, sound bovine enamel by using confocal laser scanning microscopy (CLSM) after toothbrush abrasion tests. METHODS: Sound bovine enamel specimens whose Vickers Hardness Number ranged from 280 to 320 were prepared. To measure abrasion, specimens were allocated to groups on the basis of tooth brushing stroke frequencies. Tooth brushing stroke frequencies were categorized into 5 groups: 1,800, 5,400, 10,800, 21,600 and 43,200 strokes. Both infiltration depth of Icon(R) and the abrasion depth were measured by CLSM. RESULTS: Mean infiltration depth of Icon(R) for sound bovine enamel was 98.6 microm. There was no statistically significant difference in enamel abrasion depth between groups with 5,400 strokes and 10,800 strokes, but the abrasion depth increased with further increase in tooth brushing stroke frequencies (P<0.001). The mean abrasion depth of resin infiltrated bovine enamel after 43,200 tooth brushing strokes was 17.45 microm. CONCLUSIONS: The magnitude of abrasion after 43,200 tooth brushing strokes, which corresponds to brushing 3 times a day for 4 years, was less than 20 microm. This result suggests that abrasion by tooth brushing would not be a clinical problem for resin infiltrated enamel.
Dental Caries ; Dental Enamel ; Hardness ; Microscopy, Confocal ; Stroke ; Tooth

OBJECTIVES: The aim of this study was to compare the remineralization effect of the topical fluoride agents on artificial enamel caries, under the chemical pH cycling model, using surface microhardness. METHODS: Bovine enamel specimens, embedded in acrylic resin with the labial surfaces exposed, were developed artificial enamel caries. Thereafter, this study used 56 samples on VHN 25-45. The experimental groups were divided into 4 groups: control, 2% NaF solution, 1.23% APF gel, 5% NaF varnish. Samples, except in the control group, were applied to each topical fluoride agent for 4 minutes. All groups were exposed to a pH cycling model, which consisted of demineralization (4 hours) and remineralization (20 hours) for 17 days. The Vickers surface microhardness number (VHN) was measured, using the microhardness tester. The results were analyzed, using a repeated measures analysis of variance of a general linear model, and compared the baseline, each day, using a contrast analysis (simple) about within a subject factor at a significance level of 0.05. RESULTS: Result of a repeated measures analysis regarding the surface microhardness of topical fluoride agents, there were significant differences at P-values of within and between the subject factor (P<0.001, 0.034). VHN of the experiment groups were higher than that of the baseline, until 10 days after a fluoride application, except in the control group (P<0.001). However, there were no significant differences between VHN at the baseline and 14 days after a fluoride application (P>0.05). CONCLUSIONS: In this study, although there were significant differences at P-values of within and between the subject factor, there were no significant differences between the experiment groups on chemical pH cycling model in vitro, and it was limited to utilize this result in a clinical situation of the fluoride application.
Dental Enamel ; Fluorides ; Hydrogen-Ion Concentration ; Linear Models ; Paint

OBJECTIVES: The purpose of this study was to evaluate the oral health behaviors of Korean male workers and analyze the variables affecting oral health behavior. METHODS: This study used data from the 2014 Korean National Health and Nutrition Examination Survey (KNHNES), from which 1,341 male workers who answered the questionnaires were selected. The data were analyzed by chi-squared test and logistic regression using PASW Statistics 18.0 (SPSS Inc., Chicago, IL, USA), and 95% confidence intervals were computed. Logistic regression analysis was used to assess the relationship between oral health behaviors and demographic characteristics. RESULTS: Oral health behaviors varied according to the male worker's job. Brushing teeth two or more times a day varied with levels of stress. The prevalence of people who use supplementary oral hygiene devices was 49.5%. It was increased in male workers with a spouse or high educational level (P<0.05). In addition, office workers were more likely than laborers (P<0.05) to use a supplementary oral hygiene device. The prevalence of people who brush their teeth before sleep was 41.8%. Young male workers (20-39 years old) were more likely to brush their teeth before sleep than senior workers (≥60 years old) (P<0.05). CONCLUSIONS: It is necessary to prepare a plan to promote an interest in dental hygiene in laborers and those who work in the agricultural and fishing industries. Oral health education, oral health programs, campaigns, oral check-up systems, and improvements in working environments are needed to improve the oral health behaviors of male workers.
Education ; Humans ; Logistic Models ; Male* ; Nutrition Surveys ; Oral Health* ; Oral Hygiene ; Prevalence ; Spouses ; Tooth