피스톤 온도저감 방안과 그 효과에 관한 연구

민병순(Byung Soon Min),김중수(Joong Soo Kim),최재권(jae Kwon Choi) 한국자동차공학회 1999 한국 자동차공학회논문집 Vol.7 No.3

齒根切除術 및 齒根切斷術의 症例報告

閔丙淳(Byung Soon Min) 대한치과의사협회 1984 대한치과의사협회지 Vol.22 No.3

韓國人의 小臼齒 硬組織 微小硬度에 關한 硏究

閔丙淳(Byung Soon Min) 대한치과의사협회 1977 대한치과의사협회지 Vol.15 No.1

카본 디포짓 형성에 대한 가솔린 엔진 오일의 열화와 온도의 영향

민병순(Byung-Soon Min),김중수(Joong-Soo Kim),이두순(Doo-Soon Lee),오대윤(Dae-Yoon Oh),최재권(Jae-Kwon Choi) 한국자동차공학회 1997 한국자동차공학회 춘 추계 학술대회 논문집 Vol.1997 No.6_1

In order to establish a new temperature criterion to prevent the pistons from ring sticking due to deposit formation, bench test and engine test were performed. Bench test results show that oil oxidation is more effective to the deposit formation than oil nitration. The temperature increase accelerates deposit formation and deposit formation increase rapidly above 260℃. Especially, in case of degraded oil, the deposit formation increases so rapidly that ring sticking can occur. The effect of piston temperature on the deposit formation was confirmed by engine test.<br/>

불화물(弗化物)의 상아질도포효과(象牙質塗布效果)에 관(關)한 실험적(實驗的) 연구(硏究)

전동문,민병순,최호영,박상진,Chun, Dong-Moon,Min, Byung-Soon,Choi, Ho-Young,Park, Sang-Jin 대한치과보존학회 1988 Restorative Dentistry & Endodontics Vol.13 No.1

In order to investigate the material formed by application of fluoride on human dentin, exposed dentin of tooth cervix and sound dentin powder was treated by several fluoride solutions. The former was observed by scanning electron microscope and the latter was analysed by x-ray diffractometer and infrared spectrophotometer. The results obtained were as follows: 1. Application with NaF, $SnF_2$ and $Na_2PO_3F$ on exposed dentin of tooth cervix formed mineralized materials covered. 2. The amount of mineralized materials increased with time intervals of applying the fluorides. 3. The density of mineralized materials was highest in $Na_2PO_3F$ treatment group, and NaF treatment group was higher than $SnF_2$ treatment group. 4. $SnF_2$ remained in covering of mineralized materials. 5. Application with NaF and $Na_2PO_3F$ formed mineralized materials characterized apatitic crystals. 6. The crystallinity of mineralized materials was higher prominently in $Na_2PO_3F$ treatment group.

수종(數種) 근관충진재(根管充眞材)의 근관폐쇄성(根管閉?性)에 관(關)한 실험적(實驗的) 연구(硏究)

박선희,민병순,최호영,박상진,Park, Sun-Hee,Min, Byung-Soon,Choi, Ho-Young,Park, Sang-Jin 대한치과보존학회 1988 Restorative Dentistry & Endodontics Vol.13 No.1

The purpose of this study was to evaluate and compare the sealing ability of ZOE, FR and AH-26. Seventy two upper and lower anterior and premolor teeth were randomly selected and instrumented in a conventional method with K-file. After instrumentation and dry the canal, the teeth were divided into 3 groups and twenty four teeth in each group were filled with ZOE, FR, and AH-26 respectively. All the specimens were immersed into Indian Ink and decalcified in nitric acid and cleared in methyl salicylate. The apical leakage was evaluated by measuring the degree of ink penetration with caliper at the intervals of 1 day, 7 days and 14 days. The results were as follows; 1. In AH-26 and FR groups, there was increase in penetration related to increased time of immersion in the ink. 2. FR group showed the least penetration in 3 groups. 3. Statistics showed that there was no significant difference among the each sealer groups.

복합레진 인레이 수복시 와동형태에 따른 치아파절에 관한 유한요소법적 연구

김철순,민병순,Kim, Chull-Soon,Min, Byung-Soon 대한치과보존학회 1994 Restorative Dentistry & Endodontics Vol.19 No.1

Fracture of cusp, on posterior teeth, especially those carious or restored, is major cause of tooth loss. Inappropriate treatments, such as unnecessarily wide cavity preparations, increase the potential of further trauma and possible fracture of the remaining tooth structures. Fracture potential may be directly related to the stresses exerted upon the tooth during masticatory function. The purpose of this study is to evaluate the fracture resistance of tooth, restored with composite resin inlay. In this study, MOD inlay cavity prepared on maxillary first premolar and restored with composite resin inlay. Three dimensional finite element models with eight nodes isoparametric solid element, developed by serial grinding-photographing technique. These models have various occlusal isthmus and depth of cavity, 1/2, 1/3 and 1/4 of isthmus width and 0.7, 0.85 and 1.0 of depth of cavity. The magnitude of load was 474 N and 172 N as presented to maximal biting force and normal chewing force. These loads applied onto ridges of buccal and lingual cusp. These models analyzed with three dimensional finite element method. The results of this study were as follows : 1. There is no difference of displacement between width of occlusal isthmus and depth of cavity. 2. The stress concentrated at bucco-mesial comer, bucco-disal comer, pulpal line angle and the interface area between internal slopes of cusp and resin inlay. 3. The vector of stress direct to buccal and lingual side from center of cavity, to tooth surface going on to enamel. The magnitude of vector increase from occlusal surface to cervix. 4. The crack of tooth start interface area, between internal slop of buccal cusp and resin inlay. It progresses through buccopulpal line angle to cervix at buccomesial and buccodistal comer. 5. The influence with depth of cavity to fracture of tooth was more than width of isthmus. 6. It would be favorable to make the isthmus width narrower than a third of the intercuspal distance and depth of cavity is below 1 : 0.7.

근관세척제(根管洗滌劑) 및 근관충전방법(根管充塡方法)에 의(依)한 근관폐쇄효과(根管閉鎖效果)에 관(關)한 실험적(實驗的) 연구(硏究)

오병원,민병순,최호영,박상진,Oh, Boeng-Won,Min, Byung-Soon,Choi, Ho-Young,Park, Sang-Jin 대한치과보존학회 1983 Restorative Dentistry & Endodontics Vol.9 No.1

The purpose of this study was to examine the influence of canal irrigants and the method of canal filling on the quality of canal obturation. Sixty extracted human teeth with single root were selected and divided into three different groups; In group I (control); 5 cc normal saline irrigated after each instrumentation In group II; 2.5 cc-3% NaOCl in combination with 2.5 cc-3% $H_2O_2$ In group III; RC-Prep in combination with 5 cc-3% NaOCl All specimens were cleaned, shaped(#50 file size), irrigated and obturated by lateral condensation and automated thermatic condensation filling method of gutta-percha and AH-26. After all the specimens were immersed in 2% methylene blue dye solution in $37^{\circ}C$ for 7 days and the degree of dye penetration into the canals observed by magnifying glass(${\times}$20) and reflected light microscope The results were as follows: 1. All the the teeth showed some degree of the dye penetration. 2. There were no significant difference among three groups in the degree of the dye penetration in each canal filling method. 3. There were no significant difference of the dye penetration between each canal filling method in group I. 4. There were no statistically significant difference of the dye penetration between each canal filling method in group II and group III, but lateral condensation group was showed slightly more than automated thermatic condensation group.

구치부용 복합 레진 가열시 물리적 성질의 변화에 관한 실험적 연구

박연홍,민병순,최호영,박상진,Park, Yeon-Hong,Min, Byung-Soon,Choi, Ho-Young,Park, Sung-Jin 대한치과보존학회 1989 Restorative Dentistry & Endodontics Vol.14 No.1

The purpose of this study was to examine the effect of temperature dependence of the behavior on the physical properties of posterior composite resins. Three light cure posterior composite resins (Heliomolar, Litefil-P, and P-50) and one chemical cure posterior composite resin (Bisfil-II) were used as experimental materials. Composite resin was placed in a cylindrical brass mold (2.5 mm high and 6.5 mm inside diameter) that was rested on a glass plate. Another flat glass was placed on top of the mold, and the plate was tightly clamped together. After the mold had been filled with the light cure composite material, the top surface was cured for 30 seconds with a light source. Chemical cure resin specimens were made in the same manner as above. Three hundreds and twenty composite resin specimens were constructed from the four composite materials. One hundred and sixty specimens of them were placed in a heater at $50^{\circ}C$, $75^{\circ}C$, $100^{\circ}C$, $125^{\circ}C$, $150^{\circ}C$, $175^{\circ}C$ and $200^{\circ}C$ for 5 minutes or 10 minutes respectively before compressive strengths were measured. Another one hundred and sixty specimens were tested for the diametral tensile strengths in the same way as above. They were randomly divided into eight groups according to the mode of heating methods as follows and stored in distilled water at $37^{\circ}C$ for 24 hours. Group $37^{\circ}C$ - specimens were stored at $37^{\circ}C$ in distilled water for 24 hours. Group $50^{\circ}C$ - specimens were heated at $50^{\circ}C$ after curing. Group $75^{\circ}C$ - specimens were heated at $75^{\circ}C$ after curing. Group $100^{\circ}C$ - specimens were heated at $100^{\circ}C$ after curing. Group $125^{\circ}C$ - specimens were heated at $125^{\circ}C$ after curing. Group $150^{\circ}C$ - specimens were heated at $150^{\circ}C$ after curing. Group $175^{\circ}C$ - specimens were heated at $175^{\circ}C$ after curing. Group $200^{\circ}C$ - specimens were heated at $200^{\circ}C$ after curing. Twenty specimens of each of four composite resins were respectively made by insertion of materials into same mold for examining the dimensional changes between before and after heating. The final eighty specimens were stored in distilled water at $37^{\circ}C$ for 24 hours before testing the dimensional changes. Compressive and diametral tensile strengths were measured crosshead speed 1mm/minute and 500Kg in full scale with a mechanical testing machine (DLC 500 Type, Shimadzu Co., Japan). Dimensional changes were determined by measuring the diametral changes of eighty specimens with micrometer (Mitutoyo Co., Japan). Results were as follows: 1. Diametral tensile strengths of specimens in all groups were increased with time heated compared with control group except for that in group $50^{\circ}C$ and the maximum diametral tensile strength was appeared in the specimen of Litefil-P heated for 10 minutes at $100^{\circ}C$. In heliomolar and P-50, it could be seen in the specimen heated for 10 minutes at $150^{\circ}C$, but in Bisfil-II, it could be found in the specimen heated for 5 minutes at $150^{\circ}C$. 2. Compressive strengths of specimens in all groups was tended to be also increased with time heated but that in group $50^{\circ}C$ and the maximum compressive strengths were showed in the same specimens conditioned as the diametral tensile strengths of four composite materials tested. 3. In Heliomolar, Litefil-P, and Bisfil-II, it was decreased in diameters of resin specimens between before heating and increased in diameters of resin specimens after storing in distilled water, but it was not in P-50. 4. There is little

감염근관내(感染根管內) 수종균(數種菌)에 대(對)한 항생제(抗生劑)의 감수성검사(感受性檢査)에 관(關)한 실험적(實驗的) 연구(硏究)

정영표,민병순,최호영,박상진,Chung, Young-Pyo,Min, Byung-Soon,Choi, Ho-Young,Park, Sang-Jin 대한치과보존학회 1983 Restorative Dentistry & Endodontics Vol.9 No.1

The rational approach to antimicrobial therapy of infected root canals is based on accurate identification of the infecting organism and on the organism's susceptibility to antimicrobial agents as measured by standardized techniques. In establishing criteria for the selection of antibiotics, a susceptibility test should be performed. The purpose of this study was to investigate the susceptibility of 224 aerobic and anaerobic microbial strains isolated from infected root canals to various antibiotics. This was performed by using 7 antibiotic sensi-disc: Penicillin (10 units), Ampicillin (10 mcg), Tetracycline (30 mcg), Streptomycin (10 mcg), Kanamycin (30 mcg), Lincomycin (2 mcg), and Clindamycin (2 mcg). The results were as follows; 1. Strains isolated from infected root canals was shown to be most susceptible to Clindamycin, while Streptomycin exhibited least antibacterial properties. 2. Anaerobes were found to be susceptible to Penicillin, Ampicillin, and Clindamycin. 3. Streptomycin and Kanamycin were shown to be effective against Staphylococcus aureus and Staphylococcus epidermis, however, unidentified G(+) cocci organisms were found to be resistant to these agents. 4. Bifidobacterium sp. was susceptible to Lincomycin while G(+) rods were resistant to it. 5. Staphylococcus aureus, Micrococcus sp., and anaerobes were highly susceptible to Clindamycin. 6. All of the antibiotics tested were shown to be very effective against Eubacterium sp.