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Off Pump Total Arterial Myocardial Revascularization (동맥 도관만을 이용하여 체외심폐순환 없이 시행한 관상동맥우회술)

  • Youn Young Nam;Lee Kyo Joon;Lee Gy Jong;Joo Hyun Chul;Lim Sang Hyun;Kim Seung Ho;Kwak Young Lan;Yoo Kyung Jong
    • Journal of Chest Surgery
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    • v.38 no.5 s.250
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    • pp.349-356
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    • 2005
  • Background: Arterial conduits using in coronary artery bypass grafting (CABG) have been known a great long term patency rates, and improved short and long term clinical outcomes. It has been reported that Off pump CABG has better clinical results than CABG using cardiopulmonary bypass. To evaluate the advantage of arterial conduits over venous conduits and to avoid the adverse effects of cardiopulmonary bypass, we performed total arterial Off pump CABG. Material and Method: From January 2001 to October 2004, Off pump CABG using only arterial conduits was performed on 325 patients with a mean age of $59.3\pm11.9$ years ($36\~83$). Mean ejection fraction was $55.4\pm14.0\%\;(15\~86).$ Angiography showed left main disease or triple-vessel disease in $81.9\%$ of the patients. Indications of using arterial conduits was stenosis $\ge50\%$ of left anterior descending artery, stenosis $\ge80\%$ of branches of left circumflex artery, and stenosis $\ge90\%$ of right coronary artery and its branches. Multi-slice computed tomography was performed on 194 patients to evaluate the short term patency rates. Result: A total of 928 distal anastomoses were performed and the average anastomoses per a patient were $2.86\pm0.78$. There was 1 operative mortality. Postoperative complications were mediastinitis in 6 patients ($1.8\%$), renal failure in 4 patients ($1.2\%$), perioperative myocardial infarction in 3 patients ($0.9\%$), reoperation for bleeding in 3 patients ($0.9\%$). There was no postoperative stroke. Patency rate of arterial conduits was $99.3\%$ (581/585). There were 4 stenoses or competitive flows in 2 radial arteries and 2 right internal mammary arteries. Conclusion: Total arterial Off pump CABG appears to be safe, showing a low surgical mortality and morbidity and excellent short term patency rates of arterial conduits.

Clinical Results and Optimal Timing of OPCAB in Patients with Acute Myocardial Infarction (급성 심근경색증 환자에서 시행한 OPCAB의 수술시기와 검색의 정도에 따른 임상성적)

  • Youn Young-Nam;Yang Hong-Suk;Shim Yeon-Hee;Yoo Kyung-Jong
    • Journal of Chest Surgery
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    • v.39 no.7 s.264
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    • pp.534-543
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    • 2006
  • Background: There are a lot of debates regarding the optimal timing of operation of acute myocardial infarction (AMI). Off pump coronary artery bypass grafting (OPCAB) has benefits by avoiding the adverse effects of the cardio-pulmonary bypass, but its efficacy in AMI has not been confirmed yet. The purpose of this study is to evaluate retrospectively early and mid-term results of OPCAB in patients with AMI according to transmurality and timing of operation. Material and Method: Data were collected in 126 AMI patients who underwent OPCAB between January 2002 and July 2005, Mean age of patients were 61.2 years. Male was 92 (73.0%) and female was 34 (27.2%). 106 patients (85.7%) had 3 vessel coronary artery disease or left main disease. Urgent or emergent operations were performed in 25 patients (19.8%). 72 patients (57.1%) had non-transmural myocardial infarction (group 1) and 52 patients (42.9%) had transmural myocardial infarction (group 2). The incidence of cardiogenic shock and insertion of intra-aortic balloon pump (IABP) was higher in group 2. The time between occurrence of AMI and operation was divided in 4 subgroups (<1 day, $1{\sim}3\;days,\;4{\sim}7\;days$, >8 days). OPCAB was performed a mean of $5.3{\pm}7.1$ days after AMI in total, which was $4.2{\pm}5.9$ days in group 1, and $6,6{\pm}8.3$ days in group 2. Result: Mean distal an-astomoses were 3.21 and postoperative IABP was inserted in 3 patients. There was 1 perioperative death in group 1 due to low cardiac output syndrome, but no perioperative new MI occurred in this study. There was no difference in postoperative major complication between two groups and according to the timing of operation. Mean follow-up time was 21.3 months ($4{\sim}42$ months). The 42 months actuarial survival rate was $94.9{\pm}2.4%$, which was $91.4{\pm}4.7%$ in group 1 and $98.0{\pm}2.0%$ in group 2 (p=0.26). The 42 months freedom rate from cardiac death was $97.6{\pm}1.4%$ which was $97.0{\pm}2.0%$ in group 1 and $98.0{\pm}2.0%$ in group 2 (p=0.74). The 42 months freedom rate from cardiac event was $95.4{\pm}2.0%$ which was $94.8{\pm}2.9%$ in group 1 and $95.9{\pm}2.9%$ in group 2 (p=0.89). Conclusion: OPCAB in AMI not only reduces morbidity but also favors hospital outcomes irrespective of timing of operation. The transmurality of myocardial infarction did not affect the surgical and midterm outcomes of OPCAB. Therefore, there may be no need to delay the surgical off-pump revascularization of the patients with AMI if surgical revascularization is indicated.

Comparison of Blood and Urine Renal Indices Between Hypercalciuric and Non-hypercalciuric Hematuria Patients (혈뇨 환아에서 고칼슘뇨군과 비고칼슘뇨군의 혈액 및 소변화학검사와 신기능 지표들의 비교)

  • Lee, Jin-Hee;Lee, Hyun-Seung;Lee, Keun-Young;Jang, Pil-Sang;Lee, Kyung-Yil;Kim, Dong-Un
    • Childhood Kidney Diseases
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    • v.11 no.2
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    • pp.168-177
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    • 2007
  • Purpose : The purpose of this study was to investigate whether hypercalciuria patients with hematuria show different renal indices compared to non-hypercalciuria patients with hematuria. Methods : We retrospectively reviewed the medical records of patients with gross or microscopic hematuria whose blood chemistry and 24 hour urine chemistry were examined. After excluding the patients with more than $4 mg/m^2/day$ proteinuria or the patients with urinary calcium excretion between 3 and 4 mg/kg/day, we divided the patients into two groups: a hypercalciuria group whose calcium excretion was more than 4 mg/kg/day(n=30) and a non hypercalciuria group whose calcium excretion was less than 3 mg/kg/day(n=41). The urinary excretion, clearance, and fractional excretion(FE) of Na, K, Cl, Ca, P, urea, and creatinine were calculated and compared between the two groups. Results : The hypercalciuria group had more calcium excretion($6.1{\pm}2.9$ vs $1.5{\pm}0.9 mg/kg/day$), more urea excretion($341{\pm}102$ vs $233{\pm}123 mg/kg/day$), greater glomerular filtration rate(GFR) ($93.7{\pm}31.1$ vs $79.5{\pm}32.0 mL/min$) but lower FENa($1.0{\pm}0.4%$ vs $1.3{\pm}0.6%$) than the nonhyper-calciuria group, although the urinary sodium excretion was similar between the two groups. Conclusion : The greater urea excretion and GFR in hypercalciuric patients suggest that they might be on a higher protein diet than the non-hypercalciuria group. The increased glomerular filtration of sodium and calcium induced by the higher GFR in hypercalciuria would have increased their delivery to the distal tubule, where sodium is effectively reabsorbed but calcium is not, which is suggested by the lower FENa but higher FECa in hyercalciuria. It is recommended that the diet of hematuria patients be reviewed in detail at initial presentation and during treatment.

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Long-term Survival Analysis of Bronchioloalveolar Cell Carcinoma (기관세지폐포암의 장기결과분석)

  • Lee Seung Hyun;Kim Yong Hee;Moon Hye Won;Kim Dong Kwan;Kim Jong Wook;Park Seung Il
    • Journal of Chest Surgery
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    • v.39 no.2 s.259
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    • pp.106-110
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    • 2006
  • Background: Bronchioloalveolar carcinoma (BAC) is an uncommon primary malignancy of the lung, and it accounts for $2{\~}14\%$ of all pulmonary malignancies. According to World Health Organization (WHO) categorisation, BAC is a subtype of adenocarcinoma. The current definition of BAC includes the following: malignant neoplasms of the lung that have no evidence of extrathoracic primary adenocarcinoma, an absence of a central bronchogenic source, a peripheral parenchymal location, and neoplastic cells growing along the alveolar septa. Previous reports had demonstrated a better prognosis following surgery for patients affected by BAC than those affected by other type of non-small cell lung cancer (NSCLC). We aim to analyse Asan Medical Center experiences of BAC. Material and Method: Between 1990 and 2002, 31 patients were received operations for BAC. We analyse retrosepectively sex, age, disease location, preoperative clinical stage, postoperative pathologic stage & complications, survival according to medical record. Result: There were 12 men and 19 women, the average age was 61.09$\pm$10.63 ($31{\~}79$) years. Tumor locations were 7 in RUL, 1 in RML, 4 in RLL, 8 in LUL, 11 in LLL. Operations were 28 lobectomies, 2 pneumonectomies. Postoperative pathologic stage were 12 T1N0M0, 15 T2N0M0, 1 T1N1M0, 1 T1N2M0, 1 T2N2M0, 1 T1N0M1. Mortality were 4 cases ($12.9\%$) and there were no early mortality. Cancer free death was 1 cases, other 3 were cancer related deaths. All of them were affected by distal metastasis and received chemotherapy and each metastatic locations were right rib, brain, and both lung field. The average follow up periods were 50.87$\pm$24.77 months. The overall 3, 5-year survival rate among all patients was $97.1\%,\;83.7\%$, stage I patients overall 2, 5year survival rate was $96.3\%$. The overall disease free 1, 2, 5-year survival rate among all patients was $100\%,\;90\%,\;76\%$ and 2, 5-year survival rate in cases of stage I was $96.4\%,\;90.6\%$. 7 cases ($22.58\%$) were chemotherapies, 1 case ($3.22\%$) was radiation therapy, and 2 cases ($6.45\%$) were chemoradiation therapies. Metastatic locations were 3 cases in lung, 1 case in bone, 1 cases in brain. Conclusion: BAC has a favourable survival and low recurrence rate compare with reported other NSCLC after operative resections.

Midterm Patency after Off-Pump Coronary Artery Bypass Grafting (심폐바이패스없이 심박동상태에서 시행한 관상동맥우회술후 중기 개통율)

  • Lee, Cheul;Chang, Woo-Ik;Lim, Cheong;Kim, Ki-Bong;Chae, In-Ho;Oh, Byung-Hee;Lee, Myoung-Mook;Park, Young-Bae
    • Journal of Chest Surgery
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    • v.34 no.8
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    • pp.583-590
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    • 2001
  • The aim of this study was to compare one-year graft patency after coronary artery bypass grafting without cardiopulmonary bypass(OPCAB) with that of conventional CABG and that of on-pump beating CABG, and to demonstrate any differences in patency of various conduits among the three groups. Material and Method: We analyzed the results of OPCAB cases(group I; n=122) compared with those of conventional CABG cases(group II; n=65) and those of on-pump beating CABG cases(group III; n=19). In group I, coronary angiography(CAG) was performed immediately postoperatively and 1 year after surgery. In group II and III, CAG was performed 1 year after surgery. Graft patency was graded as grade A(excellent), grade B(fair), or grade O(occluded). Result: The average number of distal anastomoses in groups I, II, and II were 3.1$\pm$1.1, 3.7$\pm$0.9, and 3.6$\pm$0.9, respectively. In group I, postoperative CAG was performed in 92%(112/122) of patients before discharge. The patency rate(grade A+B) was 96.4$(162/168) for arterial grafts, and 85.6%(160/187) for saphenous vein grafts(SVG). One-year follow-up CAG was performed in 74%(90/122) of patients. The patency rate was 97.8%(132/135) for arterial grafts, and 67.9%(106/156) for SVG. In group II, one-year follow-up CAG was performed in 65%(42/65) of patients. The patency rate(grade A+B) was 93.5%(43/46) for arterial grafts, and 86.8%(33/38) for SVG. Conclusion: Our results demonstrated that the patency rate of SVG after OPCAB was significantly lower than that of arterial grafts in the early postoperative CAG(p<0.001), and was also significantly lower than those of SVG of group II(p<0.001) and group III(p<0.01) in the postoperative one-year CAG, although there was no significant difference is one-year patency of arterial grafts among the three groups. Our data suggest that a specific perioperative anticoagulant therapy may be advisable in patients undergoing OPCAB with SVG.

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THE EFFECT OF IRRADIATION MODES ON POLYMERIZATION AND MICROLEAKAGE OF COMPOSITE RESIN (광조사 방식이 복합레진의 중합과 누출에 미치는 영향)

  • Park, Jong-Jin;Park, Jeong-Won;Park, Sung-Ho;Park, Ju-Myong;Kwon, Tae-Kyung;Kim, Sung-Kyo
    • Restorative Dentistry and Endodontics
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    • v.27 no.2
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    • pp.158-174
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    • 2002
  • The aim of this study was to investigate the effect of light irradiation modes on polymerization shrinkage, degree of cure and microleakage of a composite resin. VIP$^{TM}$ (Bisco Dental Products, Schaumburg, IL, USA) and Optilux 501$^{TM}$ (Demetron/Kerr, Danbury, CT, USA) were used for curing Filtek$^{TM}$ Z-250 (3M Dental Products, St. Paul., MN, USA) composite resin using following irradiation modes: VIP$^{TM}$ (Bisco) 200mW/$\textrm{cm}^2$ (V2), 400mW/$\textrm{cm}^2$ (V4), 600mW/$\textrm{cm}^2$ (V6), Pulse-delay (200 mW/$\textrm{cm}^2$ 3 seconds, 5 minutes wait, 600mW/$\textrm{cm}^2$ 30seconds, VPD) and Optilux 501$^{TM}$ (Demetron/Kerr) C-mode (OC), R-mode (OR). Linear polymerization shrinkage of the composite specimens were measured using Linometer (R&B, Daejeon, Korea) for 90 seconds for V2, V4, V6, OC, OR groups and for up to 363 seconds for VPD group (n=10, each). Degree of conversion was measured using FTIR spectrometer (IFS 120 HR, Bruker Karlsruhe, Germany) at the bottom surface of 2 mm thick composite specimens V2, Y4, V6, OC groups were measured separately at five irradiation times (5, 10, 20, 40, 60 seconds) and OR, VPD groups were measured in the above mentioned irradiation modes (n=5 each). Microhardness was measured using Digital microhardness tester (FM7, Future-Tech Co., Tokyo, Japan) at the top and bottom surfaces of 2mm thick composite specimens after exposure to the same irradiation modes as the test of degree of conversion(n=3, each). For the microleakage test, class V cavities were prepared on the distal surface of the ninety extracted human third molars. The cavities were restored with one of the following irradiation modes : V2/60 seconds, V4/40 seconds, V6/30 seconds, VPD , OC and OR. Microleakage was assessed by dye penetration along enamel and dentin margins of cavities. Mean polymerization shrinkage, mean degree of conversion and mean microhardness values for all groups at each time were analyzed using one-way ANOVA and Duncan's multiple range test, and using chi-square test far microleakage values. The results were as follows : . Polymerization shrinkage was increased with higher light intensity in groups using VIP$^{TM}$ (Bisco) : the highest with 600mW/$\textrm{cm}^2$, followed by Pulse-delay, 400mW/$\textrm{cm}^2$ and 200mW/$\textrm{cm}^2$ groups, The degree of polymerization shrinkage was higher with Continuous mode than with Ramp mode in groups using Optilux 501$^{TM}$ (Demetron/Kerr). . Degree of conversion and microhardness values were higher with higher light intensity. The final degree of conversion was in the range of 44.7 to 54.98% and the final microhardness value in the range of 34.10 to 56.30. . Microleakage was greater in dentin margin than in enamel margin. Higher light intensity showed more microleakage in dentin margin in groups using VIP$^{TM}$ (Bisco). The microleakage was the lowest with Continuous mode in enamel margin and with Ramp mode in dentin margin when Optilux 501$^{TM}$ (Demetron/Kerr) was used.

Postoperative Radiotherapy in the Rectal Cancers Patterns of Care Study for the Years of $1998\~1999$ (직장암의 방사선치료에 대한 Patterns of Care Study: $1998{\sim}1999$년도 수술 후 방사선치료 환자들의 특성 및 치료내용에 대한 분석결과)

  • Kim, Jong-Hoon;Oh, Do-Hoon;Kang, Ki-Moon;Kim, Woo-Cheol;Kim, Won-Dong;Kim, Jung, Soo;Kim, June-Sang;Kim, Jin-Hee;Kil, Hak-Jae;Suh, Chang-Ok;Sohn, Seung-Chang;Ahn, Yong-Chan;Yang, Dae-Sik
    • Radiation Oncology Journal
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    • v.23 no.1
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    • pp.22-31
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    • 2005
  • Purpose : To conduct a nationwide survey on the principals in radiotherapy for rectal cancer, and produce a database of Korean Patterns of Care Study. Materials and Methods : We developed web-based Patterns of Care Study system and a national survey was conducted using random sampling based on power allocation methods. Eligible patients were who had postoperative radiotherapy for rectal cancer without gross residual tumor after surgical resection and without previous history of other cancer and radiotherapy to pelvis. Data of patients were Inputted to the web based PCS system by each investigators in 19 institutions. Results : Informations on 309 patients with rectal cancer who received radiotherapy between 1998 and 1999 were collected. Male to female ratio was 59 : 41, and the most common location of tumor was lower rectum ($46\%$). Preoperative CEA was checked in $79\%$ of cases and its value was higher than 6 ng/ml in $32\%$. Pathologic stage were I in $1.5\%$, II in $32\%$, III in $53\%$, and IV in $1.6\%$. Low anterior resection was the most common type of surgery and complete resection was peformed in $95\%$ of cases. Distal resection margin was less than 2 cm in $30\%$, and number of lymph node dissected was less than 12 in $31\%$. Chemotherapy was peformed in $91\%$ and most common regimen was 5-FU and leucovorine ($59\%$). The most common type of field arrangement used for the initial pelvic field was the four field box (Posterior-Right-Left) technique ($65.0\%$), and there was no AP-PA parallel opposing field used. Patient position was prone in $81.2\%$, and the boost field was used in $61.8\%$. To displace bowel outward, pressure modulating devices or bladder filling was used in $40.1\%$. Radiation dose was prescribed to isocenter in $45.3\%$ and to isodose line in 123 cases ($39.8\%$). Percent delivered dose over $90\%$ was achieved in $92.9\%$. Conclusion : We could find the Patterns of Care for the radiotherapy in Korean rectal cancer patients was similar to that of US national survey. The type of surgery and the regimen of chemotherapy were variable according to institutions and the variations of radiation dose and field arrangement were within acceptable range.

The Effects of Preoperative Radiation Therapy in Resectable Rectal Cancer - in view of pathologic aspects - (절제 가능한 직장암에서 수술전 방사선 치료의 효과 -병리 조직학적인 연구를 중심으로-)

  • Choi, Ihl-Bong;Jang-Ji-Young;Kim, In-Ah;Shinn-Kyung-Sub;Lee, Jong-Suh;Chang-Suk-Kyun;Choi, Kyu-Young;Kim, Young-Ha;Kim, Jun-Gi;Chun-Chung-Soo;Kay-Chul-Seung
    • Radiation Oncology Journal
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    • v.15 no.1
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    • pp.49-56
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    • 1997
  • Purpose : To evaluate the pathologic effects of preoperative radiotherapy o the resectable distal rectal cancer, we analyzed the results of postoperative pathologic findings for the patients with preoperative radiotherapy ant surgery Materials and Methods: From July 1995 to April 1996, we treated sixteen patients of resectable rectal cancer with preoperative radiation therapy and curative surgery At diagnosis, Thomas Jefferson (TJ) system was used for the clinical stage of the Patients. We treated the patients with conventional radiation therapy of 4500~5000cGy before surgery. The surgery was carried out 4 weeks after completion of radiation therapy. Modified Astler Coller (MAC) system was used for the postoperative pathologic stage. We analyzed the pathologic stages and findings according to preoperative clinical stage and compared with those of the control group in similar clinical stages. Result : All patients were treated with sphincter preservation surgery after Preoperative radiation therapy. Pathoiogic complete response (CR) was shown in 1 case $(6.3\%)$. We compared the results between preoperative radiation therapy group (Preop.RT group) and surgery only group (control group). In TJ stage II, among nine patients of Preop.RT group, 8 patients $(88.9\%)$ were in MAC stage 8 except 1 CR patient, but among 17 patients of control group. 11 patients$(64.7\%)$ were in MAC stage B and 6 Patients $(35.3\%)$ in MAC stage C. In TJ stage III, among 7 patients of Preop.RT group, 4 patients $(57.1\%)$ were in MAC stage B and 3 patients$(42.9\%)$ in MAC stage C. Among 14 Patients of control group, 4 patients $(28.6\%)$ were in MAC stage B and 10 Patients $(71.4\%)$ in MAC stage C. Above results showed that postoperative Pathologic stage was decreased in Preop.RT group with statistical significance (P=0.049). The postoperative Pathologic findings (blood vessel invasion. Iymphatic vessel invasion, perineural invasion) were decreased in the Preop.RT group compared with those of control group. But statistical significance was found only in Iymphatic vessel invasion (p=0.019). Conclusion : The Postoperative pathologic stages and adverse Prognostic pathologic findings were decreased in preoperative radiation therapy group. The Iymphatic vessel invasion and MAC stage C findings were abruptly decreased in Preoperative radiation therapy group. The preoperative radiation therapy was found to be effective in resectable rectal cancer. The patients group in our study was very small and long term follow up was not done. Therefore, further study about this issues is needed.

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Fracture load and marginal fitness of zirconia ceramic coping by design and coloration (유색 및 백색 지르코니아 세라믹 코핑의 코핑 디자인에 따른 파절 하중과 변연 적합성)

  • Shin, Mee-Ran;Kim, Min-Jeong;Oh, Sang-Chun
    • The Journal of Korean Academy of Prosthodontics
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    • v.47 no.4
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    • pp.406-415
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    • 2009
  • Purpose: The purpose of this study was to compare the marginal fitness and fracture load of the zirconia copings according to the design with different thickness and coloration. Material and methods: The evaluation was based on 80 zirconia copings. Zirconia copings were fabricated in design with different thicknesses using CAD/CAM system (Everset, KAVO dental GmbH, Biberach, Germany). The designs of copings were divided into four groups. The first group consisted of copings with uniform thickness of 0.3 mm. The thickness in the second group was 0.3 mm on the buccal surface and 0.6 mm on the lingual surface. The third group consisted of coping with uniform thickness of 0.6 mm. The thickness in the fourth group was 0.6 mm on the buccal surface and 1mm on the lingual surface. Each group consisted of 10 colored and 10 uncolored copings. Half of the copings (40) processed with a milling system according to the specific design were sent to be given a color (A3) through saturation in special dye by a manufacturing company. Just after sintering, the marginal discrepancies of copings were measured on the buccal, lingual, mesial and distal surfaces of metal die, under a Video Microscope System (sv-35, Sometech, Seoul, Korea) at a magnification of $\times$ 100. It was remeasured after the adjusting of the inner surface. Next, all copings were luted to the metal dies using reinforced cement {GC FujiCEM (GC Corp. Tokyo, Japan)} and mounted on the testing jig in a Universal Testing Machine (Instron 4467, Norwood, MA, USA). The results were analyzed statistically using the one-way ANOVA test. Results: The obtained results were as follow: 1. The measured value of marginal discrepancy right after sintering was the greatest in the contraction of the buccal area in all groups, except for group I2. 2. There was no significant difference of marginal fitness among the groups in the colored zirconia group (P<.05). 3. When the marginal fitness among the groups in the uncolored zirconia group was considered, group II2 had the smallest marginal discrepancy. 4. When the colored and uncolored groups with the same design were compared, there was a significant difference between I1 and II1 groups. In group 2, 3, and 4, the uncolored zirconia had the greatest marginal fitness (P<.05). 5. After adjustment of inner surface, there was no significant difference in the marginal fitness in all groups when color and design of the zirconia coping were compared. 6. The fracture load of CAD/CAM zirconia copings showed significant difference in group 1, 2, 3, and 4. I4 and II4 had the strongest fracture load. 7. When groups with different color and same design were compared, all colored groups showed greater fracture load (P>.05), with no significance. Conclusion: There was difference in the marginal fitness according to the design and coloration of zirconia copings right after sintering, but it was decided that the copings may well be used clinically if the inner surface are adjusted. The copings should be thick enough for the reinforcement of fracture strength. But considering the esthetics of the visible surfaces (labial and buccal surface), the thickness of copings may be a little thin, without giving any significant effect on the fracture strength. This type of design may be considered when giving priority to preservation of tooth or esthetics.

A Study on Corrosion according to Distance between Amalgam and Dissimilar Metals (아말감과 이종(異種)금속의 거리에 따른 부식에 대한 고찰)

  • Kim, Ju-won;Jeong, Eun-gyeong
    • Journal of dental hygiene science
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    • v.4 no.3
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    • pp.103-109
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    • 2004
  • The present study prepared 72 test samples - 24 made of amalgam alloy, 24 of Verabond (Ni-Cr alloy) for crown and 24 of Talladium $^{TM}alloy$ for denture - according to the manufacturers' manuals and general method in consideration of the width of the mesial-distal dental crown of the lower $1^{st}$ molar and MOD cavity in clinics, put them in a 200 ml beaker containing 80 ml of artificial saliva, and measured their galvanic corrosion at distances of 0 mm, 7 mm and 40 mm after 7 days. Isolated metals in the electrolyte such as Cu, Ag, Ni, Cr, Sn, Zn and Hg were quantitatively analyzed with Inductively Coupled Plasma - Atomic Emission Spectrometer (ICP-AES, JY-50P, VG Elemental Co. France), and from the results were drawn conclusions as follows. First, Cu, Sn, Ag, Hg and Zn were highly advantageous when amalgam contacted gold alloy compared to Ni-Cr alloy for crown and Talladium alloy for denture. In addition, although gold alloy was finest in terms of oral tissue and biocompatibility, it was most disadvantageous when it was with amalgam. Second, when amalgam contacted gold alloy, heavy metals such as Ni and Cr were not isolated at all because gold alloy did not contain such elements but Sn was isolated as much as $227.1{\pm}18.0035{\mu}g/cm^2$ although it was not included in the composition either. Hg was also isolated. These elements are assumed to have been isolated from amalgam itself. Third, when amalgam alloy was apart from gold alloy 0 mm, 7 mm and 40 mm, Cu and Ag showed significance but Hg did not. This suggests that gold alloy must not be used together with amalgam, and must not be used between dissimilar prostheses regardless of distance. Fourth, when amalgam alloy contacted Ni-Cr alloy for crown, Ag was not isolated from the amalgam, but Zn, Ni, Sn, Hg and Cu were isolated in order of quantity. Significance was observed according to distance - 0 mm, 7 mm and 40 mm. Hg was not isolated but heavy metals Ni and Cr were isolated. If amalgam alloy was in the opposite arch or it was apart from Ni-Cr alloy for crown, the isolation Hg was less than that when amalgam alloy contacted Ni-Cr alloy for crown. Fifth, when amalgam alloy contacted Talladium alloy for denture, significance was observed at distances of 0mm, 7 mm and 40 mm. Hg was not isolated but heavy metals Ni and Cr were isolated. If amalgam alloy was in the opposite arch or it was apart from Talladium alloy for denture, the isolation Hg was less than that when amalgam alloy contacted Talladium alloy for denture. Sixth, according to the result of ICPES test on Cu, Sn, Ag, Hg, Zn, Ni and Cr of amalgam alloy, gold ally, Verabond and Talladium alloy when these alloys contacted artificial saliva, significance was observed in Cu and Hg. Seventh, when amalgam alloy contracted two non-precious metals Ni-Cr alloy for crown and Talladium alloy for denture in artificial saliva, significance was observed in the isolated by-products of Hg, Ni and Cr according to distance.

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