방사선학적 치근단병소의 크기와 특징에 대한 치근단낭종 및 육아종의 상관관계연구

최호식,이우철,손원준,금기연,배광식,백승호 大韓齒科保存學會 2010 Restorative Dentistry & Endodontics Vol.35 No.1

The purpose of this study was to find out the relationship of radiographic lesion size, gender, age of patients and radiographic character to the diagnosis of periapical cyst and granuloma. The data was collected from 187 periapical lesions of 167 patients who undergone apical surgery at Department of Conservative Dentistry, Seoul National University Dental Hospital from 2003 to 2005. The lesion were surgically removed and send for biopsy to the Oral Pathology Laboratory. From the initial radiograph, lesion size was calculated using PiViweSTAR (INFINITT, Korea) program. The obtained data were statistically evaluated using SPSS (p<0.05). The result were as followings: 1. From 187 biopsy samples, the incidence of periapical cyst was 28.34% and granuloma was 65.24%. 2. There was a significant correlation between periapical cyst and the size of radiographic lesion (p<0.01). 3. There were no significant correlations between age, gender, location of lesion and the final diagnosis (p>0.05). 4. There was a significant correlation between the non-demarcation of the lesion and the incidence of periapical granuloma (p<0.01). 본 연구는 2003년부터 2005년까지 서울대학교 치과병원 보존과에 내원한 환자 중 치근단수술을 시행한 환자 167명에서 생검을 위해 적출한 187개의 치근단병소를 대상으로 하였다. 수술 후 조직검사 결과 얻은 진단명과 환자의 진단기록에서 환자의 성별, 나이, 발병 부위, 방사선 사진 상의 특징 그리고 병소의 크기와의 상관관계를 조사하였다. 초진시 방사선 사진에서 치근단병소의 크기를 PiViewSTAR (INFINITT, Korea)를 이용하여 화소를 계산함으로써 면적을 구하였다. 이를 바탕으로 통계 분석프로그램 SPSS (version 12.0K, SPSS Inc., Chicago, IL, USA)를 이용해 방사선사진상 크기와 진단명과의 상관관계를 조사하였다. 나이와 진단명과의 상관관계는 일원배치 분산분석을 시행하고 성별, 부위, 방사선사진상의 특징과 진단명과의 상관관계는 교차분석을 통해 카이제곱검정으로 조사하여 다음과 같은 결론을 얻었다. 1. 187의 치근단병소 조직검사결과 치근단병소 중 치근단낭종의 비율은 28.34%, 육아종의 비율은 65.24%, 기타병소의 비율은 6.42%로 나타났다. 2. 방사선사진상 병소의 크기가 커질수록 치근단 낭종일 확률이 높았다(p<0.01). 3. 나이, 성별, 발병부위와 진단명사이에서 유의 한 상관관계가 없었다(p>0.05). 4. 병소의 경계가 명확하지 않은 것과 치근단육아종의 발생빈도는 통계적으로 유의한 상관관계를 보였다(p<0.01).

고속 ATM 네트워크를 위한 통신 프로토콜에 관한 연구

박기현,안기중,이상배,강문식 연세대학교 산업기술연구소 1992 논문집 Vol.24 No.1

In this paper, a new network protocol, AD²R(ATM Distributed queue Dual Ring), is proposed for high-speed communication. This protocol is a slotted using ATM scheme. With the mathematical analysis and computer simulation, it is shown that proposed protocol is appropriate for the high-speed communication. Also, it is verified that the AD²R network performance is enhanced by using the ring topology, the destination release and the distributed queue scheme.

알렉시딘과 차아염소산나트륨의 화학적 상호반응 후 mass spectrometry를 이용한 파라클로로아닐린의검출 분석

김현식,한승현,오소람,임상민,구유,금기연 大韓齒科保存學會 2010 Restorative Dentistry & Endodontics Vol.35 No.4

근관세척제인 NaOCl과 CHX를 병행 사용하는 경우 적갈색의 발암물질로 알려진 PCA가 생성된다. 본 연구의 목적은 CHX와 유사한 buigunide 계통의 소독제 인 ALX을 NaOCl 과 흔합 반응 시 PCA가 생성되 는지 여부를 mass spectrometry를 이용하여 평가하고자 하였다. 대조군으로는 4% NaOCl 용액과 2% CHX의 혼합용액, 0.5%PCA 용액, 및 1%ALX 용액을 사용하였고 실험군으로는 5가지 농도(1%, 0.5%, 0.25%, 0.125%, 0.0625%)의 ALX 용액과 4% NaOCl의 흔합용액을 질량분석기를 이용하여 mole-cular peak를 분석한 결과 ALX과 NaOCl의 혼합물에서는 PCA(m/w=128)로 보이는 128 피크가 관찰되지 않았다. 또한 용액의 색 변화에서도 ALX이 농도가 높을수록 열은 노랑색을 띄었으나 농도가 낮아질수록 흰색으로 관찰되었으며 어떠한 침전물의 형성도 보이지 않았다. Recent studies demonstrated that the combination of chlorhexidine (CHX) and sodium hypochlorite (NaOCl) resulted in the formation of a precipitate, para-chloroaniline (PCA). Alexdidine (ALX) is a kind of biguanides like CHX, and has stronger detoxification effect against the bacterial virulence factors such as lipoteichoic acid and lipopolysacchardide compared with CHX. The purpose of this study was to determine whether PCA was formed after chemical interaction between ALX and NaOCl using mass spectrometry. Mass spectrometry was performed for the mixture of five different concentrations of ALX (1, 0.5, 0.25, 0.125, 0.0625%) and 4% NaOCl. Results showed that the peak of PCA was not detected in mixed solu tions of ALX and NaOCl in mass spectrometry analysis. The color of mixed solution of ALX and NaOCl after chemical interaction was light yellow to white, but there wasn't any precipitate found.

산업평균 재무비율이 개별기업의 재무비율결정에 미치는 영향

석기준,황윤식 東亞大學校 1995 東亞論叢 Vol.32 No.-

The traditional literature of financial statement analysis often emphasizes the desirsbility of adjusting the firm's finacial ratios to prdetermined targets which are usually based on industry-wide averages. This study considers the question of whether there is empirical evidence to suggest that firms do adjust their financial ratios to such targets. The results of the test, using the partial adjustment model, indicate that financial ratios are periodically adjusted to their industry means. The speed of adjustment to the target is indicated by the size of the βcoefficient : the closer βis to 1, the faster the periodic adjustment. The extent of partial adjustment is rationalized by economists in terms of two conflictin types of costs : (a) the cost of adjustment and (b) the cost of being out of equilibrium. According to the stability of the target argument, we would expect small adjustment coefficients for industries experiencing fast technological changes.

재정지원사업에 관한 실증적 연구

석기준,황윤식 東亞大學校 經營問題硏究所 2003 經營論叢 Vol.24 No.-

Drosophila busckii의 韓國集團에서 있어서 同位酵素 多形現象

成耆昌,尙椿植,金彧,金大鎰 성균관대학교 기초과학연구소 1985 論文集 Vol.36 No.1

Genetic structure and variability were investigated in four Korean populations of Drosophila busckii. Eight allozyme loci were analysed by means of starch gel electrophoresis. The proportions of polymorphic loci and loci heterozygous per individual were estimated to be 0.25 and 0.051, respectively. The average genetic similarity between four populations was found to be S―=0.977. This value is similar to the other Drosophila populations reported. However, the gene variation of D. busckii in this study appeared to be the least variable among 28 Drosophila species reported. It is suggested that the low gene variation in D. busckii might be due to adaptation of this species to a narrow niche, but the possibility of occurrence of the random drift cannot be excluded.

事象硏究 設計上의 諸問題

石琪濬,黃允植 東亞大學校 大學院 1992 大學院論文集 Vol.17 No.-

전치부 반대교합을 동반한 환자에서의 수직고경 회복

계기성,최우식,이선아 조선대학교 구강생물학연구소 2002 Oral Biology Research (Oral Biol Res) Vol.26 No.2

In cases of anterior crossbite patients, there are many problems. They are dissatisfied with facial appearance and in difficulties for speaking, and sometimes are related to reduced vertical dimension. Vertical dimension is defined distances between two points which one is on maxilla and the other is on mandible. Loss of vertical dimension may causes temporomandibular disorder, loss of masticatory function, and collapse of occlusion. This is a clinical study of 50 years old male with reduced vertical dimension and anterior-crossbite. We treated patient with fixed bridge and conventional removable partial denture, and then the activity of masseter and temporalis muscle were recorded and analyzed by means of Biopak?? system(Bioresearch Inc., Millwakee Wisconsin). The result was satisfactory functionally and esthetically.

감염성심내막염에서 심초음파도의 역할

김기식 대한순환기학회 1998 Korean Circulation Journal Vol.28 No.9

치과용 고농도Pd계 금-은-팔라듐합금의 시효경화특성

이기대,이화식 대구보건대학 2001 대구보건대학 論文集 Vol.21 No.-

An Ag-Pd-Cu alloys containing a small amount of Au is commonly used for dental purposes, because this alloy is cheaper than Au-base alloys for clinical use. However, the most important characteristic of this alloy is age-hardenability, which is not exhibited by other Ag-base dental alloys. Dental Ag-Pd-Cu alloys exhibit the characteristics of age-hardenability. Palladium represses the sulphurization of silver, and the age-hardenability is caused by the addition of copper. In order to improve the corrosion resistance, a small amount of gold is added to the commercial alloys. The specimens used were Ag-Pd-Cu ternary alloy and Ag-Pd-Cu-Au alloy. These alloys were melted and casted by induction electric furnace and centrifugal casting machine in Ar atmosphere. They were rolled and drawn into plate and wire shape. These specimens were solution treated for 2hr at 800℃ and were then quenched into iced water, and aged at 350~550℃ Principal results are as follows : Hardening occured in two stages, stage Ⅰ in low temperature and stage Ⅱ in high temperature regions, during continuous aging. From the electron microscope study, it was concluded that the cause of age-hardening in this alloy is the precipitation of the PdCu ordered phase. It was very effective that addition of small amount of Au increased hardenability in Ag base dental alloy and increasing the Pd content of Ag base alloys also increased base dental alloy and increasing the Pd content of Ag base alloys also increased hardenability. The formation of the lamellar structure develpoed from grain boundaries by discontinuous precipitation. Ag-Pd-Cu alloy is more effective dental alloy as ageing treatment and is suitable to isothermal ageing at 450℃.