치주 치료 후 치아 상실에 관한 연구

김형섭,석정진,김현철,이수정,최승환,Kim, Hyung-Seop,Seok, Jeong-Jin,Kim, Hyun-Chul,Lee, Su-Jeong,Choi, Seoung-Hwan 대한치주과학회 2003 Journal of Periodontal & Implant Science Vol.33 No.2

The main goal of periodontal treatment is the long-term maintenance of teeth. Periodic maintenance program is need to prevent periodontal disease and maintain healthy periodontium. Hirschfeld and Wasserman(1978) studied 600 treated periodontal patients. This study categorized periodontal patients using well-maintained, downhill, extreme downhill groups. The purpose of our study is to evaluate effect of periodontal treatment and analyse tooth loss after periodontal treatment using this classification. The study population of j9 patients had been treated and maintained for mean 5.8 years. All patients were on a periodic maintenance program at 2-, 3-, 4, or 6-month intends. The avenge age of the patients at the time of original therapy was 49.6 years. To analyse tooth loss, modified classification was used on the basis of response to therapy using by Hirschfeld and Wasserman in 1978. The results were as follows : 1. 59 treated patients were lost mean 1.42 teeth per patient for 5.8 years of maintenance period. 2. Maxillary first molars were most frequently lost but mandibular lateral incisors were lost no tooth during maintenance period. 3. Tooth mortality received surgical treatment had similar to received nonsurgical treatment. 4. Tooth loss was more frequent in maxillary teeth than mandibular teeth, and posterior teeth than anterior teeth, and more frequent tendency in male than female.

염화수은의 신장독성 지표 반응성 비교연구

김형섭 ( Hyung Sub Kim ),김용순 ( Yong Soon Kim ),임채형 ( Chae Hyung Lim ),곽승준 ( Seung Jun Kwack ),조영래 ( Young Rae Cho ),강미선 ( Mi Sun Kang ),오재호 ( Jae Ho Oh ),조완섭 ( Wan Seob Cho ),한범석 ( Bum Seok Han ),김승희 ( S 한국동물실험대체법학회 2007 동물실험대체법학회지 Vol.1 No.2

To compare the responsiveness of nephrotoxicity parameters, mercuric chloride(HgCl2) was administered intraperitoneally at the doses of 0.2, 0.6 and 1.0 mg / kg for different exposure periods(1, 3 and 7 days) using F344N rats. We compared several parameters resulted from animal study(body weight change, organ weight), clinical pathological(serum and urine chemistry), histopathological study and toxicogenomic study. Animal body weight significantly decreased and kidney weight(relative) increased in a dose-dependent manner. Serum chemistry analysis showed that BUN and creatinine were relatively one of nephrotoxicity biomarkers against HgCl2 and serum chemistry analysis was more sensitive than urine analysis. In the histopathological study, dose and time-dependency was clearly observed. Cellular swelling was observed in the low dose(0.2 mg / kg) group(1 day treatment) and focal inflammation including cellular swelling was observed in the high dose group. In the DNA microarray analysis, gene expression profiles were analysed in the 1-day and 3-days treatment group. Taken together, the responsiveness of individual parameter(body weight change, organ weight, clinical pathology, histopathology and DNA microarray) was different. This study suggests that these considerations should be involved in the analysis of toxicity study data as well as toxicogenomic study could provide a useful information to reduce the number of experimental animals used in the repeated toxicity study.

리어가이더 시작각 변화가 횡류홴 성능에 미치는 영향

김형섭(Hyung-Sub Kim),김동원(Dong-Won Kim),윤태석(Tae-Seok Yoon),박성관(Sung-Kwan Park),김윤제(Youn J. Kim) 대한기계학회 2004 대한기계학회 춘추학술대회 Vol.2004 No.4

A cross-flow fan relatively makes high dynamic pressure at low speed because a working fluid passes through an impeller blade twice and blades have a forward curved shape. Therefore, the performance of a cross-flow fan is influenced 25% by the impeller, 60% by the rearguider and the stabilizer, 15% by the heat exchanger. At the low flow rate, there exists a rapid pressure head reduction, a noise increase and an unsteady flow against a stabilizer and a rearguider. Moreover, it is difficult to analyze the reciprocal relations of the cross-flow fan because each parameter is independent. Numerical analyses are conducted with different starting angles of the rearguider. Two-dimensional, unsteady governing equations are solved, using FVM, PISO algorithm, sliding grid system and κ?ε standard turbulence model.

연구논문 : 염화수은의 신장독성 지표 반응성 비교연구

김형섭 ( Hyung Sub Kim ),김용순 ( Yong Soon Kim ),임채형 ( Chae Hyung Lim ),곽승준 ( Seung Jun Kwack ),조영래 ( Young Rae Cho ),강미선 ( Mi Sun Kang ),오재호 ( Jae Ho Oh ),조완섭 ( Wan Seob Cho ),한범석 ( Bum Seok Han ),김승희 ( S 한국동물실험대체법학회 2007 동물실험대체법학회지 Vol.1 No.2

To compare the responsiveness of nephrotoxicity parameters, mercuric chloride(HgCl2) was administered intraperitoneally at the doses of 0.2, 0.6 and 1.0 mg / kg for different exposure periods(1, 3 and 7 days) using F344N rats. We compared several parameters resulted from animal study(body weight change, organ weight), clinical pathological(serum and urine chemistry), histopathological study and toxicogenomic study. Animal body weight significantly decreased and kidney weight(relative) increased in a dose-dependent manner. Serum chemistry analysis showed that BUN and creatinine were relatively one of nephrotoxicity biomarkers against HgCl2 and serum chemistry analysis was more sensitive than urine analysis. In the histopathological study, dose and time-dependency was clearly observed. Cellular swelling was observed in the low dose(0.2 mg / kg) group(1 day treatment) and focal inflammation including cellular swelling was observed in the high dose group. In the DNA microarray analysis, gene expression profiles were analysed in the 1-day and 3-days treatment group. Taken together, the responsiveness of individual parameter(body weight change, organ weight, clinical pathology, histopathology and DNA microarray) was different. This study suggests that these considerations should be involved in the analysis of toxicity study data as well as toxicogenomic study could provide a useful information to reduce the number of experimental animals used in the repeated toxicity study.

구강 점막에 발생한 유표피 낭종 2예

김형섭(Hyung Seob Kim),이준호(Jun Ho Lee),박찬흠(Chan Hum Park),홍석민(Seok Min Hong) 대한두경부종양학회 2008 대한두경부 종양학회지 Vol.24 No.1

Epidermoid cysts can be found anywhere in the body, particularly in areas where embryonic elements fuse together. Most cases have been reported in the ovaries, the testicles, as well as the hand and feet. Epidermoid cysts in mouth are uncommon and account for less than 0.01% of all oral cysts. The treatment of choice is complete surgical excision and prognosis is excellent. The purpose of this article is to describe two cases of an epidermoid cyst in the oral cavity mucosa and a review of the literature.

연어 회귀 하천인 양양 남대천에서 수질과 섬유소 분해율의 계절적 분석

김규중,김형섭,박광하,안태석 ( Kyu Joong Kim,Hyung Seop Kim,Kwang Ha Park,Tae Seok Ahn ) 한국하천호수학회 1996 생태와 환경 Vol.29 No.1

The analyses of physicochemical factors and the distribution of microbial populations were measured at seven sites from May, 1994 to April, 1995 in Yangyang Namdaecheon river, Kwangwon-do. Abrupt increases of nitrogen and phosphate salt values were showed from area below the Yangyang old bridge, Ohsackcheon and Namdaecheon, parallel with the increase of cellulose degradation rate. The cellulose degradation rate was highly correlated with the degree of temperature, the concentration of NO_3-N, the population of fecal coliform bacteria and heterotrophic bacteria. The attached bacteria on cellulose film at Ohsackcheon were succeeded from high density of rod form to low density of filamentous form.

Nd:YAG 레이저 조사시 치근면에 미치는 효과에 관한 주사전자현미경적 연구

이수정,김수아,서석란,김형섭,Lee, Su-Jeong,Kim, Soo-Ah,Seo, Seok-Ran,Kim, Hyung-Seop 대한치주과학회 1997 Journal of Periodontal & Implant Science Vol.27 No.3

The purpose of this study was to evaluate the in vitro effects of Nd:YAG laser irradiation on removal of a root surface smear layer after root planing in comparison with Tetracycline HCl. The 60 extracted human teeth due to severe periodontal disease were vigorously scaled and root planed with Gracey curet. Thirty specimen($5{\times}5{\times}2mm$) were obtained from root planed surface of 30 human teeth and assigned randomly to one of three groups : root planed group(5 specimen), Tetracycline HCI group(5 specimen, burnished for 5 minutes), and Nd:YAG laser group(25 specimen, German Dental Laser, Fotona Twinlight). Nd:YAG laser group was divided into 4 subgroups according to power of 1W, 1.5W, 2W, 3W at frequency to 10Hz. The specimen were then fixed, and examed by Scanning electron microscopic study. 30 of 60 human teeth used to measurement of the intrapulpal temperature rise during laser irradiation. Laser-irradiated surface exhibited various surface texture from relative flat surface to irregular surface with patent dentinal tubules of various shape and size. In some area, the root surface alteration which are carbonization, pit and crater formation and melting and resolidification were observed. The number of exposed dentinal tubules per unit($100_{\mu}m^2$) on tetracycline HCI group was more than that in the laser group below 1.5W of power(150mJ/pulse) and was significantly less than that in laser group above 2W of power(200mJ/pulse)(P<0.OOl). As power increased the intrapulpal temperature rise also increased. The result suggested that the parameter which effectively remove root surface smear layer than tetracycline HCI may cause thermal damage to pulp and root surface alteration result from laser exposure would indicate need for additional instrumentation. Thus, Nd:YAG laser irradiation in these parameter may not be appropriate for clinical use as adjunct to conventional periodontal therapy.

제거된 ePTFE 막의 주사전자현미경적 소견과 치주임상상태의 비교연구

박정민,최병선,이석초,김형섭,Park, Jeong-Min,Choi, Byung-Son,Lee, Seok-Cho,Kim, Hyung-Seop 대한치주과학회 1996 Journal of Periodontal & Implant Science Vol.26 No.1

Ten intrabony defects in 10 patients were treated by flap surgery including root surface debridement and placement of an expanded polytetrafluoroethylene(ePTFE) membrane. The membranes were removed after 4-6 weeks. This study was performed to examine the retrived ePTFE membrane by scanning electron microscopy(SEM) for bacterial contamination and adherent connective tissue elements, and to compare it with clinical conditions. The cervical portion of the membrane, which in most cases had become partially exposed to the oral cavity, had a bacterial deposit. Small bacterial colonies and a scatter of single cells in some instances extended into the apical portion of the membrane. Fibroblast-like cells, erythrocytes and fibrous structures were seen in the apical portion of the membrane. Outer surface of membrane tends to more bacterial contamination than inner surface(p<0.01), and upper portions more than lower portions(P<0.01). Comparison of ultrastructural findings and clinical conditions revealed that extent of bacterial contamination of the membrane correlated with gingival inflammation and extent of membrane exposure, but it was not significant statistically. The results suggested that gingival inflammation and membrane exposure affect periodontal regeneration by the use of ePTFE membrane.

Substance P가 T 임파구의 세포증식과 IL-2 생산에 미치는 영향

문진균,최병선,이석초,김형섭,Moon, Jin-Kyun,Choi, Byung-Son,Lee, Seok-Cho,Kim, Hyung-Seop 대한치주과학회 1997 Journal of Periodontal & Implant Science Vol.27 No.4

Immune responses of periodontal tissue may be regulated by products of sensory afferent nerve endings such as neuropeptides. Substance P(SP), a tachykinin neuropeptide, has been previously reported to stimulate the activities of T lymphocyte. Therefore, I examined the role of SP in IL-2 production and cell proliferation by using a homogeneous line of T lymphocytes(Jurkat and HuT78). Cell proliferation rate was determined by [$^3H$]-thymidine incorporation test, and IL-2 was quantitated by the growth rate of CD4+ IL-2-dependent T lymphocyte line CTLL-2. SP stimulated cell proliferation of T lymphocytes at the concentration of $10^{-12}$ and $10^{-8}$M in a biphasic bell-shape dose-dependent manner. However, SP alone did not induce IL-2 release at the concentration range of $10^{-6}$ to $10^{-14}$M. The upregulation of IL-2 release was observed when $10^{-12}$M SP was applied together with mitogens such as Con A or PHA+PMA on T cell lines, especially on Jurkat. Con A or PHA+PMA demonstrated to increase the rate of cell proliferation of Jurkat, which had shown to produce much amount of IL-2 indicating that mitogen-induced cell proliferation might be partially influenced by released IL-2. It was concluded that regulatory effects of SP on the immune/inflammatory response could be mediated through the costimulatory upregulation of IL-2 production and increase of cell proliferation of T lymphocyte.

치주염증시 ${\gamma}-Glutamyl$ transpeptidase의 연구

이석초,임종득,유광렬,오귀옥,김형섭,Lee, Seok-Cho,Lim, Jong-Deuk,Yoo, Kang-Rgeol,Oh, Kwi-Ok,Kim, Hyung-Seop 대한치주과학회 1993 Journal of Periodontal & Implant Science Vol.23 No.3

Glutathione(GSH),a tripeptide thiol, found in virtually all cells, functions in metabolism tranasport and cellular protection. It protects cells against the destructive effects of reactive oxygen intermediates and free radicals. Also ${\gamma}-Glutamyl$ transpeptidase(${\gamma}-GTT$), an enzyme of major importance in GSH metabolism, initiates GSH degradation. In order to explore the $GSH-{\gamma}-GTT$ system as periodontal disease activity indicator, we observed the ${\gamma}-GTT$ and arachidonic acid metabolits according to clinical groups(Control, Adult periodontitis, Rapidly progressive Periodontitis). From the experiments, the following results were obtained. 1. When compared with normal, ${\gamma}-GTT$ of A. P. and R. P. P. were increased, and only the change of ${\gamma}-GTT$ of R. P. P. was statistically significant(P<0. 05). 2. The amounts of arachidonic acid metabolites were not different with statistical significance among the clinical groups. 3. ${\gamma}-GTT$ may by useful adjuncts as new cytoprotective indicator and periodontal disease activity indicator in accordance with positive corelation pocket depth, attachment level and ${\gamma}-GTT$.