1.Biological Effects of bioactive glass and natural coral on periodontal ligament fibroblast-like cell behavior.
The Journal of the Korean Academy of Periodontology 1999;29(1):173-192
The purpose of this study was to evaluate the effects of bioactive glass and natural coral on the human periodontal ligament fibroblast(HPLF) behaviors during the regeneration process of peridontium. To determine the cellular events occuring in the presence of the particles of bioactive glass and natural coral, HPLF were isolated from healthy premolar teeth extracted for orthodontic treatment. Cells were cultured in alphaMEM at 37degrees C, 5% CO2, 95% humidity incubator. Bioactive glass and natural coral were powdered, and each particled(<40micrometer) were placed on the cultured cells at the concentration of 0.3mg/ml, and l,0mg/ml for experimental group. In control group no particles were added. And each group was evaluated by examining the cell morphology under phase-contrast micrograph at 4 day and transmission electron micrograph(TEM) and scanning electron micrograph(SEM) at 14 day, alkaline phosphatase activity at 5 and 9 day, protain synthesis at 4 day, DNA synthesis at 1, 2, 3 and 4 day, cell proliferation at 1, 3, 5,7 and 9 day and the formation of bone nodule at 30 day after culturing all groups in mineralizing supplemented mediun. No significant changes in cell morphology by adding these two matirials were found under phase contrast microscopy and TEM, HPLF phagocytocized each particles suggesting that HPLF is involved in the process of resorbing each particles and that bioactive glass were more biocompatible than natural coral. The ALPase activity of bioactive glass 0.3 mg/ml was similar with control groups and all the rests of control groups were significantly low(P<0.01) indicating a transient dedifferentiation of HPLF in the presence of bioactive glass and natural coral particles. There were no significant differences of protein synthesis between all groups. The DNA synthesis in experimental groups were significantly lower than control groups at 1, 2 and 3 day (P<0.01) but became similar to control groups at 4 day. Between control groups, the DNA synthesis in bioactive glass 0.3mg/ml group was significantly higher than other groups(P (0.01). Cell proliferation in natural coral 1.0mg/ml and bioactive glass l.0mg/ml groups were significantly lower than control group at 3 day(P(0.05) and there were no differences at 5, 7, 9 day. There were more bone nodule formation in experimental groups than in control groups. In conclusion, these results indicated that bioactive glass and natural coral have some effects of a transient dedifferentiation on HPLF and regeneration of periodontal tissues, however any significant cytotoxic effect on HPLF by these two particles were not found.
Alkaline Phosphatase
;
Anthozoa*
;
Bicuspid
;
Cell Proliferation
;
Cells, Cultured
;
DNA
;
Glass*
;
Humans
;
Humidity
;
Incubators
;
Microscopy, Phase-Contrast
;
Periodontal Ligament*
;
Regeneration
;
Tooth
2.Clinical and microbiological investigation on the effect of doxycycline administration in the management of adult periodontitis.
Mok Hoon OH ; Chong Pyoung CHUNG ; Seong Heui SON ; Soo Boo HAN ; Sang Mook CHOI
Journal of the Korean Society for Microbiology 1992;27(5):457-470
No abstract available.
Adult*
;
Chronic Periodontitis*
;
Doxycycline*
;
Humans
3.The effects of low dose doxycycline regimen on gingival crevicular fluid enzyme actmty of diabetic patients with periodontitis and adult periodontitis patients.
Seong Nyum JEONG ; Soo Boo HAN
The Journal of the Korean Academy of Periodontology 1997;27(4):701-722
It was reported that low dose doxycycline(LDD) regimen could inhibit pathologically elevated collagenase activity in the gingival crevicular fluid of petients with adult periodontitis without producing typical antibiotic side effects. The purpose of this study was to evaluate the effects of LDD regimen(20mg) administered during non-surgical therapy on clinical index and gingival crevicular fluid enzyme activity in diabetics who are at high risk for periodontal disease. Fortynine subjects having at least two sites with probing pocket depths greater than 4mm were selected. In this double-blind, placebo-controlled study, the patients were administered 20 mg doxycycline capsule or placebo capsule b.i.d. for 2 weeks. Clinical parameters of dental plaque, gingival inflammation, probing pocket depth and probing attachment level were assessed at week 0, 2, 4, and 8. Gingival crevicular fluid samples were collected at the same time to evaluate the activities of collagenase and elastase. Clinical parameters and elastase activity were significantly reduced in all groups compared to the baseline value after treatment. Significantly greater reduction in pocket depth and gain in attachment level was shown in the LDD-administered group compared to placebo group in both adult periodontitis and diabetic patients. Total collagenase activity was also reduced significantly in all groups after treatment, but the greater reduction was seen in the LDD-administered diabetics group compared to relevant placebo group(at 4, 8week). Significantly greater reduction in active collagenase activity was also seen in the LDDadministered group compared to placebo group in diabetic patients(at 2, 4, 8week). These results indicated that use of low dose doxycycline could be aueseful adjunct to instrumentation therapy in the management of diabetic patient with periodontitis as well as adult periodontitis patient.
Adult*
;
Chronic Periodontitis*
;
Collagenases
;
Dental Plaque
;
Doxycycline*
;
Gingival Crevicular Fluid*
;
Humans
;
Inflammation
;
Pancreatic Elastase
;
Periodontal Diseases
;
Periodontitis*
;
Root Planing
4.Melanin Pigmentation In Gingiva.
The Journal of the Korean Academy of Periodontology 2003;33(2):271-276
Oral melanin pigmentation is common in some races and ethnic groups. The gingivae are the most frequently pigmented intra-oral tissues. Melanin pigmentation is the result of melanin granules, produced by melanoblasts intertwined between epithelial cells at the basal layer of the epithelium. We present one case of melanin pigmentation of the gingiva of 26-year old female. Melanin depigmentation method is applying a 90% phenol solution to deepithelize pigmented areas, gingivectomy, epithelial abrasion, bone denudation, and split thickess flap. We chose epithelial abrasion using round diamond bur. The patient satisfies the result and have almost no pain and discomfort. But repigmentation potential must be noticed to patient.
Adult
;
Continental Population Groups
;
Dental Instruments
;
Epithelial Cells
;
Epithelium
;
Ethnic Groups
;
Female
;
Gingiva*
;
Gingivectomy
;
Humans
;
Melanins*
;
Phenol
;
Pigmentation*
5.Perceived Stressors among Dental Students: a Scale Development.
Korean Journal of Medical Education 2005;17(3):285-296
PURPOSE: The purpose of this study was to investigate the perceived sources of stress among dental students. The relationships of these stresses to the year of study and gender were also examined. METHODS: The responses from the first to fourth year dental students to 30 items adapted from Dental Environment Stress (DES) questionnaire were subjected to confirmatory factor analysis. The Likert scale, ranging from 0 (not applicable) to 4 (very stressful), was applied to these items. A total of 341 students (male=196, female=145) participated, their average age being 24.7. Multivariate analysis of variance (MANOVA) was conducted to analyze the effects of the year of study and gender on stressors. RESULTS: Confirmatory factor analysis established a five-factor model including 1) clinical practice, 2) academic load and pressure, 3) personal problems, 4) low self-esteem, and 5) school administration or climate. Subscales for each factor show good internal consistency with Cronbach's alpha ranging from .71 to .88. Mean score for factor II (academic load and pressure) was the highest among all factors for all of 4 years, which meant that primary stressors were amount of classwork, shortage of time, and competition among classmates regardless of the year of study. MANOVA result showed that the amount of stress from clinical practice and school climate generally increased through the years (p < .01), and that female students were more stressed than male students (p < .01). CONCLUSION: Students' stress is related to the features of the curricula and the learning environment. In reducing this stress, it would be helpful to modify the curriculum as well as to introduce mentor or counselor programs.
Climate
;
Counseling
;
Curriculum
;
Education, Dental
;
Female
;
Humans
;
Learning
;
Male
;
Mentors
;
Multivariate Analysis
;
Prothrombin
;
Students, Dental*
;
Surveys and Questionnaires
6.The influence of Advanced Adult Periodontitis on the pulp.
kang Woon LEE ; Chul Woo LEE ; Soo Boo HAN
The Journal of the Korean Academy of Periodontology 1999;29(1):95-102
The purpose of this study was to observe histopathologically the influence of advanced periodontitis on pulp tissue, and to conclude the correlation between the results with clinical madifestations. The samples were teeth with over 7mm pocket depth and over 50% radiographic bone loss. These were diagnosed to have very poor prognosis and thus planned to be extracted. Those with any of following conditions were excluded from the samples, loss of vitality, periapical pathology, restoration or prosthesis, dental caries, and attrition or abrasion. It was because these conditions could affect pulp without any correlation with periodontal disease. For the experiment, 17 teeth from 11 patients were selected. Average age of patient was 47. Each tooth was examined for following categoris; pocket depth, gingival recession, electric pulp test, mobility, percussion test, sensitivity test. The extracted teeth were fixed buffered neutral formalin solution. It was decalcified using 4% nitric acid. Sliced histological samples observed using light microscope, for pulp status, and severeity of inflammation. 4 samples were excluded due to histologic sample discrepency. Thus 13 samples were subject to observation. 4 showed normal conditions. Focal reversable pulpitis was shown in 5 samples. Chronic pulpitis was observed 1 samples. Pulpal abscess observed in 3 samples.
Abscess
;
Adult*
;
Chronic Periodontitis*
;
Dental Prosthesis
;
Formaldehyde
;
Gingival Recession
;
Humans
;
Inflammation
;
Nitric Acid
;
Pathology
;
Percussion
;
Periodontal Diseases
;
Periodontitis
;
Prognosis
;
Pulpitis
;
Tooth
7.Scaling and Root Planing with Concomitant Subgingival Curettage.
Seok Ho JI ; Soo Boo HAN ; Chul Woo LEE
The Journal of the Korean Academy of Periodontology 1999;29(1):81-93
Non-surgical therapy is still an important technique in periodontal treatment. In this study, scaling and root planing(SRP) with or without concomitant subgingival curettage were compared clinically and microbiologically. 14 moderate adult periodontitis patients were included in this study. After 2 weeks from screening visit, with split mouth design, one quadrant was treated by SRP, and the opposite side was treated by SRP with subgingival curettage. Clinical measurement and microbiological analysis was taken at baseline, 1 month, 3 month post-treatment. Clinical parameters used in this study was probing depth, gingival recession, gingival index, bleeding on probing, plaque index, tooth mobility(Periotest Value). Microbiological analysis consisted of determination of the percentages of 4 bacterial groups according to morphologic type with phase-contrast microscope and measuring Black-pigmented Bacteroides after anaerobic culture. 1, There were significant changes in probing depth and gingival recession at 1 month(P>0.05), and these changes remained through 3 month. However, no significant differences were observed between two groups(P>0.05). 2. There were also significant reductions in gingival index and bleeding on probing at 1 month(P<0.05), and these reduced levels were maintained through 3 month with no significant differences between two groups(P>0.05). 3. In both groups, motile bacteria decreased significantly at 1 months(P<0.09), but increased nearly to baseline level at 3 month. 4. The percentages of Black-pigmented Bacteroides, in both groups, decreased significantly at 1 month(P<0.05), and in the subgingival curettage group, significant more reductions were observed than in the root planing group(P<0.05). At 3 month, significant reduction was found in subgingival curettage group only(P<0.09). According to these results, we surmised that concomitant subgingival curettage and root planing give some advantageous effect on bacterial recolonization.
Bacteria
;
Bacteroides
;
Chronic Periodontitis
;
Gingival Recession
;
Hemorrhage
;
Humans
;
Mass Screening
;
Mouth
;
Periodontal Index
;
Root Planing*
;
Subgingival Curettage*
;
Tooth
8.Microbial Contaminations of Ultrasonic Scalers, High-Speed Handpieces and Water Syringe Lines.
Beom Seok CHANG ; Jung Yun LEE ; Soo Boo HAN
The Journal of the Korean Academy of Periodontology 1997;27(4):941-947
The purpose of this study was to evaluate various methods of decontamination of ultrasonic scalers, high-speed handpieces and air-water syringes in dental equipments. Eimination of possible sources of microbial infection in dental operatories should be of primary importance. Microbial contamination levels of high speed handpieces, air-water syringes and ultrasonic scalers of 11 dental units in Seoul National University Hospital were evaluated after flushing the lines, alcohol sponge rubbing, or soaking in 0.1% chlorhexidine for 1,3 and 5 minutes. The result suggests that flushing the lines or soaking the tips in 0.1% chlorhexidine before use of the water systems may reduce the microbial levels. Soaking in 0.1% chlorhexidine for 5 minutes was most effective in reducing bacterial contamination.
Chlorhexidine
;
Decontamination
;
Dental Equipment
;
Flushing
;
Porifera
;
Seoul
;
Syringes*
;
Ultrasonics*
9.EFFECTS OF CIGARETTE SMOKING ON PERIODONTAL STATUS.
The Journal of the Korean Academy of Periodontology 2001;31(4):803-810
The purposes of this study were to investigate the relationship between cigarette smoking levels and periodontal status. 199 subjects, consisting of male 127 and female 72, classified by smoking levels and duration were selected: Patients who had smoked for more than 20 cigarettes/day were considered heavy smokers, 10 to 19, moderate smokers ; 1- 9, light smokers; 0, non-smoker. And smokers were divided into ones who had smoked for more than 20 years, 10-19 years, less than 10 years and non-smokers. Heavy smokers and moderate smokers showed significantly greater pocket depths, less clinical attachment levels, more molar furcation involvements, greater alveolar bone loss and higher scores of plaque index than light smokers and non-smokers, (p < 0.05). When the duration of smoking was considered as a factor, scores of clinical parameters were worse and alveolar bone loss were significantly greater in long-term smokers, who had smoked for more than 20 years. In conclusion, cigarette smoking is associated with periodontal status.
Alveolar Bone Loss
;
Female
;
Humans
;
Male
;
Molar
;
Smoke
;
Smoking*
;
Tobacco Products*
10.In Vitro Effects of Female Sex Hormones on Collagenase Activity of Gingival Fibroblast and Periodontal Ligament Fibroblast.
Ji Yearn SHIN ; Chul Woo LEE ; Soo Boo HAN
The Journal of the Korean Academy of Periodontology 1999;29(1):31-40
Many factors may affect periodontal changes during the physiologic conditions of woman(e.g. puberty, menstrual cycle, pregnancy, menopause). Recently many research has focused on the immunological changes of host, but the exact mechanism is not clear. Collagen is a major constituent of periodontium, and collagenase specifically digests the collagen and plays a role in destruction of periodontal tissue. So, I suppose that it participates with the cytokines in the inflammation of gingiva and vascular response during the changes of female sex hormones. Because there are some evidences of the existence of the receptors of estrogen and progesterone in the gingiva, it may be a target tissue of female sex hormones. In this experiment, gingival fibroblast and periodontal ligament cell were cultured in the presence of various concentrations of estrogen or progesterone corresponding to the menstrual cycle and pregnancy. Collagenase activity of the supernatant of culture media was determined by Spectrophotometric collagenase assay. The enzyme activity was calculated by the % decrease of the coated collagen. 1. The estrogen at both concentrations had no effect on the activity of collagenase of the gingival fibroblast. 2. The progesterone had some effect on the collagenase activity of the gingival fibroblast at low and high concentration of menstrual cycle, and elevated the enzyme activity at all range of pregnancy concentrations. 3. In periodontal ligament cells, estrogen elevated the enzyme activity at the early pregnancy concentration and progesterone elevated at the concentration just before menstruation. In this experiment, progesterone elevated the collagenase activity of gingival fibroblast and periodontal ligament cells. But the mechanism of the up-regulation of the enzyme activity was not confirmed. The more experiments of direct effect of progesterone on gingival at the molecular level(e.g. northern blot analysis) can reveal the exact mechanism.
Adolescent
;
Blotting, Northern
;
Collagen
;
Collagenases*
;
Culture Media
;
Cytokines
;
Estrogens
;
Female*
;
Fibroblasts*
;
Gingiva
;
Gonadal Steroid Hormones*
;
Humans
;
Inflammation
;
Menstrual Cycle
;
Menstruation
;
Periodontal Ligament*
;
Periodontium
;
Pregnancy
;
Progesterone
;
Puberty
;
Up-Regulation