• 대한치과보철학회지
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• 제33권2호
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• pp.210-230
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• 1995

To compare the wear resistance of four kinds of commercial acrylic resin teeth [SR-Orthosit PosterioresR(Ivoclar Co., Liechtenstein), Endura PosteriorR(Shofu Inc. Japan), trubyte IPN teethR(Dentsply International Inc., York,), Trubyte BiotoneR(dentsply Inermational Inc. Brazil) by means of the toothbrush abrasion method, the artificial resin teeth were embedded in epoxy resin with the occlusal surfaces aligned in one plane for a total of 40 blocks. There after, each lock was mounted in the arm of the toothbrush abrasion machine(K 236, Japan). Wear measurements were made on the three preconditioned states. Those were as follows : no treatment specimens, thermocycled specimens, and thermocycled specimens which were immeresed applied load of 400g during the buring the brushing cycle. At the end of the 30,000-stroke cycle, each specimen was removed, and weighed. The microhardness of four kinds of commercial resin teeth were determined by means of microhardness tester. Microhardness tests were performed on te no treatment specimens, thermocycled specimens, and thermocycled specimens with immersion in the denture cleansing solution. Finally, the comparison of thermal properties were perfomed using differential scanning calorimeter(DSC-1500). The following results were obtained : 1. In the case of no treatment teeth, the wear amount of endura Posterior(EN) was the greatest among the others(p<0.01), and the wear amount of three kinds of artificial resin teeth was increased in the order of Trubyte IPN teeth(IN), Trubyte Biotone(BN), SR-Orthosit Posteriores(SN) but there was no statistic significance(p>0.01). 2. The wear amount of Trubyte IPN teeth(IT) and Trubyte Biotone(BT), was increased due to thermocycling effect, but that of Endura Posteriores(ET) was decreased conversely(p<0.01). 3. Except for the SR-Orthosit Posteriores(STC), the wear amount of three kinds of artificial resing teeth(that is, ETC, ITC, BTC) was increased due to denture cleansing solution$(Cledent^R)$, but there was no statistic significance(p>0.01). But the wear amount of the SR-Orthosit Posteriores(STC) was the greatest among the others(p<0.01). 4. The wear amount of toothbrush was the greatest in case of contact with occlusal surface of SROrthosit Posteriores resin teeth(p<0.01). 5. the microhardness values(KHN) of the SR-Orthosit Posteriores was the highest among the experimental artificial resin teeth(p<0.01). 6. There was no relationship between microhardness valuse(KHN) and wear amount of four kinds of experimental artificial resin teeth(p<0.01). 7. The differential canning calorimetric property of four kinds of artificial resin teeth did not show endothermal or exothermal peak in the range of $100^{\circ}C$

• 대한치과보철학회지
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• 제41권5호
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• pp.674-688
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• 2003

Statement of Problem : With increasing demand of the implant-supported prosthesis, it is advantageous to use the different platform width of the fixture according to bone quantity and quality of the patients. Purpose : The purpose of this study was to assess the loading distributing characteristics of two implant designs according to each platform width of fixture, under vertical and inclined loading using finite element analysis. Material and method : The two kinds of finite element models were designed according to each platform width of future (4.1mm restorative component x 11.5mm length, 5.0mm wide-diameter restorative component x 11.5mm length). The crown for mandibular first molar was made using UCLA abutment. Each three-dimensional finite element model was created with the physical properties of the implant and surrounding bone. This study simulated loads of 200N at the central fossa in a vertical direction, 200N at the outside point of the central fossa with resin filling into screw hole in a vertical direction and 200N at the buccal cusp in a 300 transverse direction individually Von Mises stresses were recorded and compared in the supporting bone, fixture, and abutment screw. Results : The stresses were concentrated mainly at the cortex in both vertical and oblique load ing but the stresses in the cancellous bone were low in both vertical and oblique loading. Bending moments resulting from non-axial loading of dental implants caused stress concentrations on cortical bone. The magnitude of the stress was greater with the oblique loading. Increasing the platform width of the implant fixture decreased the stress in the supporting bone, future and abutment screw. Increased the platform width of fixture decreased the stress in the crown and platform. Conclusion : Conclusively, this investigation provides evidence that the platform width of the implant fixture directly affects periimplant stress. By increasing the platform width of the implant fixture, it showed tendency to decreased the supporting bone, future and screw. But, further clinical studies are necessary to determine the ideal protocol for the successful placement of wide platform implants.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권6호
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• pp.497-503
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• 2004

One of the most difficult problems to damage in dentistry is an odontogenic infection. These infections may range from low-grade, well-localized infections that require only minimal treatment to a severe, life-threatenig fascial space infection. Although the overwhelming majority of odontogenic infections are easily managed by minor surgical procedures and supportive medical therapy that includes antibiotic administration, the practitioner must constantly bear in mind that these infections may become severe in a very short time. We made an investigation was targeting on 78 male and 47 female patients (125 patients in total) who had been hospitalized because of the fascial space abscess on the oral and maxillofacial area and gained a complete recovery in Daegu Catholic University Hospital, Oral & Maxillofacial Surgery from January 1999 to December 2003. By tracing their charts, we could grasp the characteristics such as age, gender, the time of breakout and specific areas of the attacks, making a conclusive study of the statistical analysis and finally, we could reach conclusions. Now, we report the conclusion from the investigation with the literature. The proportion of males and females was approximately 3 to 2, and in age group, patients under 10 years old marked the highest, 22.4%. The patients between the age of 10 and 40 were only 14.4%, yet those who were between 40 and 80 marked 53.6% in contrast. In the monthly distribution, the order was Dec.(13.6%)-Sep.(12%)-Jan.(10.4%) and in seasonal distribution, it was winter(30.4%)-fall(28%)- summer(24.4%)- spring(19.2%). Considering the medical history, D.M. was the highest which was 30.3%, hypertension marked 24.4%, and the patients with both D.M. and hypertension were 9.0%. The major cause of infection of oral and maxillofacial areas was odontogenic infection, which marked about 96%, and especially the cases related to dental caries occurred most frequently, which was 51.2%. In the number of relaxed fascial space, single fascial space was 81.6%, and in the degree of relaxation of fascial space, the buccal space abscess marked 40.8%, following submandibular space abscess, which was 30.4%.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제34권5호
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• pp.525-531
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• 2008

CDH-13(T-cadherin), which is one of a kind among the 20 cadherins, can be found mainly in wall of aorta, neuron, spleen, blood vessel etc. It is also called H-cadherin. This structural difference can explain that CDH-13 is thought to play a key role in maintaining mutual relation between extra and intra-cellular environment rather than in cell adhesion. The main function of CDH-13 is to participate in blood vessel function. Additionally, it is known to regulate cell growth and cell contact inhibition. When cells are proliferating, cell surface perceives other cells so that substance such as CDH-13 can inhibit their growth or proliferation resulting in homeostasis without endless proliferation or invasion of connective tissue boundaries. However, tumor cell itself appears to be different from normal cells' growth, invasion or transmission. Therefore, it can be diagnosed that these characteristics are closely related to expression of CDH-13 in tumor cells. This study is to investigate expression of CDH-13 in SCC and its correlation with promoter methylation. 20 of tissue species for the study are excised and gathered from 20 patients who are diagnosed as SCC in department of OMS, dental hospital, dankook university. To find development of CDH-13 in each tissue samples, immunohistochemical staining, RT-PCR gene analysis and methylation specific PCR are processed. The results are as follows. 1.Immunohistochemical staining: In normal oral squamous epithelial tissue, strong expression of CDH-13 was found in cell plasma membrane of basal cell layer. On the other hand, in case of low-differentiated oral SCC, development of CDH-13 was hardly seen. 2.The development of CDH-13 gene: In 9 of samples, expression of CDH-13 gene could be seen and 2 of them showed low expression compared to the others. And rest of the 11 samples showed no expression of CDH-13 gene. 3.Methylation of CDH-13 gene: Among 9 samples which expressed CDH-13 gene, 7 of them showed unmethylation. In addition, among 11 samples without CDH-13 gene expression, 10 showed methylation. According to the results stated above, promoter methylation were found in 13 samples(65%) among 20 of oral SCC samples. In low-differentiated SCC, suppression of gene expression could be seen accompanying promoter methylation. These phenomenon of gene expression was proved by immunohistochemical investigation. Finally, for development of oral SCC, conclusions can be made that suppression of CDH-13 played a main role and suppression of gene expression was originated from promoter methylation. Considering this, it is expected that suppression of CDH-13 from promoter methylation to be utilized as a good diagnostic marker of oral SCC.

• Restorative Dentistry and Endodontics
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• 제35권1호
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• pp.24-29
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• 2010

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 $PiViewSTAR^{(R)}$ (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).

• Journal of Oral Medicine and Pain
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• 제37권1호
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• pp.19-25
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• 2012

2010년부터 2011년까지 양산부산대학교 치과병원 구강내과에 초진 내원한 외래환자 중 재발성 아프타성 구내궤양(RAU)으로 임상 진단된 환자 20명과 구강편평태선으로 임상진단 된 환자 33명, 부산대학교 치의학전문대학원생 59명을 대조군으로 정하고 간이정신진단검사를 시행하여 다음과 같은 결론을 얻었다. 1. RAU 환자군과 편평태선 환자군, 대조군은 9개 증상차원 기본척도의 T 점수 평균값은 모두 65 이하로 정상범위 내에 있었다. 2. RAU 환자군은 정상 대조군에 비하여 SOM 지수가 유의하게 높았으며 (P<0.05), DEP 지수에서 높은 경향을 보였다. 3. RAU의 여성 환자군은 여성 대조군에 비하여 SOM, DEP, HOS 지수가 유의하게 높았고 (P<0.05), ANX 지수에서 높은 경향을 보였다. 4. RAU 환자군은 편평태선 환자군에 비하여 HOS 지수가 유의하게 높았으며 (P<0.05), O-C, I-S, DEP 지수에서 높은 경향을 보였다.

• 지역사회간호학회지
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• 제1권1호
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• pp.582-594
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• 1989

The purpose of this study is to analyze the factors affecting the school health teachers' self-confidence. This study was conducted with 87 school health teachers working in Jeonbuk province, from September to December, 1986, The results are follows; 1. Demographic characteristics of school health teachers 1) Age mean ; 34, range; 23-54 2) School Nursing experience mean; 11 years, range; 0-24 3) Clinical experience mean; 1.5 years, range: 0-13 2. Status of school health resources & nursing activities 1) Personnel resource school health teacher: pupils : 1 : 1,436 'classes=1:31 'general teacher=1:39 2) Budget Total school operating budget: School health budget : 100 : 4.2 (52.2 thousand Won) Half of the school health budget expend on medicine. 3) Clinic 80% of all schools have health clinic seperately. 71.32 of all schools have less than $35m^2$, 23.9%, $36-66m^2$. 4) Only 20% of all schools have organization for health 5) Average of clinic visitor for 1 year; 2,084 Major problem is on digestive system. And other problem: respiratory, skin, musculo - skeletal system, dental problem, etc... 6) Literal message for 1 year; 12 times. For health education (4), vaccination (3), examination of parasites (2), etc... 3. The degrees of the school health teachers' self-confidence 1) Program planning & evaluation; 2.9. 2) Clinic management; 2.8 3) Health education; 2.8 4) Management of school environment; 2.7 5) Health care services; 2.5. 6) Operating of school health organization; 2.3 4. Significances to self-confidence on school health nursing activities 1) Program planning & evaluation: home message (r=.228, p<.05) No. of clinic visitor (r=.220, p<.05) expending time for clinic management (r=.229, p<.05) religion (t: 2.5, p<.05) level of school (F=6.3, p<.005) 2) Clinic management: age of school health teacher (r=-.202, p<.05) school health experience (r=-.211, p<.05) salary step (r=.187, p<.05) expending time for clinic management (r=.315, p<0.1) marital status (t=3.97, p<.005) level of school (F=3,139, p<0.5) 3) Management of school environment: level of school (F=3.899, p<.05) expending time for clinic management (r=-,216, p<0.5) 4) Health care service: age of school health teacher (r=-.186, p<.05) marital status (t= 3.67, pH.005) 5) Health education: expending times for clinic management (r=-.252, p<05) level of school (F=5.343, p<.01) 6) Operating of health organization; age of school health teacher (r=-.258, p<.01)salary step (r=.188, p<.05) Based on the above results, the suggestions are as follows; 1. Need to raise ,appointment rate school health teacher. 2. Need to raise self-confidence on school health nursing activities through the inservice education or re-inforcement. 3. Need to secure adequate budget for school health. 4. Participation of school health teacher and support of school master for school health services are required. 5. Need for use the health clinic seperately, adequate facilities and free utilization by visitors.

• Journal of Oral Medicine and Pain
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• 제38권3호
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• pp.235-246
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• 2013

법치의학적 연령 감정은 개인 식별에 있어 중요한 역할을 한다. 본 연구는 한국 연령 감정 대상자들의 사회적 특성을 분석하는 것을 목적으로 한다. 2012년 3월부터 2013년 3월까지 경북대학교 치과병원 구강내과에 연령 감정을 의뢰한 대상자들에게 설문조사를 실시하였다.결과는 다음과 같다: 1. 성별 분포에서, 남성(42.86%)보다 여성(57.14%)이 더 많았다. 50대와 60대 이상의 고령자가 대다수였으며(89.28%), 40대 아래로는 한 명의 의뢰인도 없었다. 의뢰인들의 대부분이 초등학교 졸업 이하의 학력을 가지고 있었다(69.64%). 2. 호적 상 연령과 의뢰인이 주장하는 연령 간의 차이가 나게 된 가장 큰 이유로는 가족 및 친척의 실수로 인한 것이 가장 많았다(80.36%). 연령 감정을 통해 얻고자 하는 목적은 사회 복지 혜택(62.50%), 사회적 인관 관계 문제(12.50%), 단지 바른 나이를 찾기 위해서(10.71%), 직업과 관련한 문제(8.93%) 순이었다. 3. 연령 감정을 하기 위해 치과(구강내과)를 찾게 된 경로로는 관공서의 비중이 높았으며(48.21%), 친구나 지인(21.43%), 대중매체(14.29%), 병의원(10.71%) 등을 통한 경로가 뒤를 이었다. 법치의학적 연령 감정에 대한 의뢰인들의 이해도는 10점 만점에 7.03점으로 높은 수준이었다. 절반 이상의 의뢰인들에게서 현재의 연령 감정 비용에 대해 만족하는 것으로 나타났다. 4. 법치의학적 연령 감정을 통해 감정된 연령과 의뢰인들이 주장하는 연령 간에는 57.14%의 근접도를 보였다. 1년 간 조사한 연령 감정 대상자들의 23.53%가 법적으로 연령 정정을 하게 되었다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제33권4호
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• pp.367-374
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• 2007

Purpose: The diagnostic relevancies and characteristics and of clinical methods in the diagnosis of internal derangement(ID) were tested by comparing the results of them with those of magnetic resonance imaging(MRI). Methods: 75 patients(150 temporomandibular joints; TMJs), who were suspected to have ID by clinical diagnoses, were included. Clinical diagnoses including mouth opening pathway and TMJ sound were conducted and MRI takings were done. Accuracies, sensitivities, specificities, positive predictive values, and negative predictive values of clinical diagnosis, mouth opening pathway, and TMJ sound were calculated by comparing with diagnoses with MRIs. Results: Accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of clinical diagnosis were 59.3%, 83%, 49%, 81%, and 51%. They were 59%, 82%, 25%, 73%, and 35% for mouth opening pathways. Although deviation was somewhat accurate for representing disc displacement with reduction(ADDWR), other discrepancies on opening pathways were not clinically relevant. Accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of clicking sounds were 85%, 49%, 78%, 85%, and 37%. TMJs with crepitus were only three. But all TMJs with crepitus were diagnosed to have disc displacement without reduction(ADDWOR). Conclusion: When compared with diagnoses with MRIs, clinical diagnoses for ID were not so accurate. But they were suitable for screening tests for ID. Opening pathways and TMJ sounds were not so relevant in the diagnoses of IDs and so it was concluded that considerations for other factors must be included in the diagnoses of IDs.

• 대한치과보철학회지
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• 제44권5호
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• pp.594-605
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• 2006

Statement of problem: Modification of titanium implant surface has potential to ensure clinically favorable performance that several surface modification technologies have been introduced. Among the methods. anodizing method and sol-gel hydroxyapatite coating method have gained much interest due to its roughness and chemical composition of the coating layer, but more of its biocompatibility result is required. Purpose : The purpose of this study was to compare bone-implant interface shear strength of four different surface treated implants as time elapsed. Resonance frequency analysis(RFA) and removal torque measurement methods were employed to measure implant stability at one week and six week after implantation. Material and method: A total of 80 screw-shaped implant [20 machined, 20 resorbable media blasted(RBM), 20 anodized, and 20 anodized+hydroxyapatite sol-gel coated] were prepared, and one of each group was implanted in the tibia of a New Zealand white rabbit that total 20 of them were used. In order to test the implant stability and implant-tissue interface contact changing in the bone bed, each 10 rabbit were sacrificed 1 week and 6 week later while resonance frequency and removal torque were measured. One-way analysis of variance and the Tukey test were used for statistical analysis. Results : The results were as follows. 1. There was no statistically significant difference of implant stability quotients(ISQ) value in RFA between individual groups after 1 week of implantation and 6 weeks(p>0.05). But, there was statistically significant increase of ISQ value in 6 weeks group compared to 1 week group(p<0.05). 2. There was no statistically significant difference in removal torque analysis between individual groups after 1 week of implantation and 6 weeks(p>0.05). but there was statistically significant increase in all 4 groups after 6 weeks compared to 1 week later(p<0.05). 3. There was no statistically significant difference in removal torque analysis between anodized group and HA coating after anodic oxidation 6 weeks later(p>0.05), but significant difference was appeared in both groups compared to RBM group and smooth-machined group(p<0.05). Conclusions : It can be suggested that changes in surface characteristics affect bone reactions. Anodized and anodized+hydroxyapatite sol-gel coating showed significantly improved bone tissue response to implants, but further study on the effect of hydroxyapatite dissolution is needed.