1.The effet of cooling rate on the residual stresses in the veneer ceramics of zirconia-ceramic restorations: a literature review.
The Journal of Korean Academy of Prosthodontics 2014;52(2):136-142
Nowadays, dental zirconia is widely used as a framework material for a fixed dental prosthesis as well as a single restoration. However, clinical studies have reported high incidence of veneer chipping of zirconia-ceramic restorations compared to that of metal-ceramics. Several factors were raised as the possible causes of veneer ceramic chipping, however, it is still in debate. Recently, residual stresses in the veneer ceramics after cooling process gathers attention as one possible cause of chipping and many studies reported that the rate of cooling significantly influenced the types and the amount of residual stress. The purpose of current review was to briefly describe the effect of cooling rate on the residual stress in zirconia-ceramics. It was also described that the different behavior of residual stress between zirconia-ceramics and metal-ceramics following different cooling rate.
Ceramics*
;
Dental Prosthesis
;
Incidence
2.Histologic change of the posterior attachment in anterior disc displacement of the temporomandibular joint - a new model of internal derangement in rabbits.
Tae Woo KIM ; Jea Seung KO ; Young Il CHANG
Korean Journal of Orthodontics 1993;23(4):503-527
This paper describes a new method to create an animal model for TMJ internal derangement in the New Zealand white rabbits and the light and electron microscopical changes of posterior attachment of them. Twenty six rabbits(2.5-3.0kg), four normal and twenty two experimental, were used. The right disc of experimental animal was displaced anteriorly without sectioning the posterior attachment and tied to the zygomatic arch with nylon not to be reduced to the original position. The left TMJ was sham-operated to be compared with its right experimental one. Normal animals were sacrificed one day and eight weeks after experiment. Experimental animals were sacrificed one day, ten days, three weeks, five weeks and eight weeks after surgery respectively. They were fixed intravenously with 2% glutaldehyde under general anesthesia and the samples of them were processed for light and electron microscopic examination. The purpose of this experiment is to make a suitable animal model of disc displacement without reduction for studying and understanding the cellular and morphologic events in posterior attachment of TMJ including early changes which were difficult to be observed in human TMJs. The results of this investigation suggest the following conclusions: 1. Authors induced anterior disc displacement surgically in rabbits with new method to examine histologic changes of posterior attachment. Tissue reactions of this model seem to be similar to those observed in human disc displacement. We think this animal model for anterior disc displacement may be used to explore and evaluate objectively the effects of many treatment modalities in disc displacements. 2. The animal disease model showed inflammation at early stage(one and ten days). At this stage there were mild-to-severe mononuclear inflammatory cell infiltration, numerous newly formed vessels, vessel dilatation and engormement and many fibroblasts. 3. At middle stage(three weeks), fibrosis occurred, where fibroblasts decreased in number, but their cytoplasm was profuse indicating high activity. Collagen fibers increased in number and the tissue looked more dense. 4. At late stage(five weeks and eight weeks) showed degenerative changes including perforation of posterior attachment, disintegration of collagen fiber bundles, degeneration of fibroblasts, metastatic ossification, and dystrophic calcification.
Anesthesia, General
;
Animals
;
Collagen
;
Cytoplasm
;
Dilatation
;
Disease Models, Animal
;
Fibroblasts
;
Fibrosis
;
Humans
;
Inflammation
;
Models, Animal
;
Nylons
;
Rabbits*
;
Temporomandibular Joint*
;
Zygoma
3.Local Pelvic Recurrence after Curative Resection of the Rectal Cancer: Classification and Prognosis.
Jea Kun PARK ; Nam Kyu KIM ; Seung Hyuk BAIK ; Kang Young LEE ; Seung Kook SOHN ; Chang Hwan CHO
Journal of the Korean Society of Coloproctology 2005;21(2):82-88
PURPOSE: The management of local recurrence after curative surgery of the rectal cancer remains difficult clinical problems to surgeons. This study was performed to analyze the outcomes of patients with local pelvic recurrence according to its recurrence type. METHODS: A total 109 patients with local recurrence were evaluated. Among the 109 patients 62 were local recurrence alone and 47 were both local and systemic recurrence. The recurrence type was classified as Central, Anterior, Posterior, Lateral and Perineal recurrence according to the relation of the tumor location and either intra pelvic organ and/or fixed pelvic structure. RESULTS: Only 26 (23.9%) of the 109 patients had curative resection and the remaining 83 (76.1%) patients had palliative exploration or nonsurgical procedure. The resectability according to the recurrence type showed that the Central and Anterior type was higher than other type of recurrences (P=0.001). When the primary operation was Abdominoperineal Resection (APR) the resectability was poorer than Low Anterior Resection (LAR) (P=0.0001). When comparing the patients with local recurrence alone, the 5 year survival rate was significantly higher patients treated by curative resection than palliative or non-resection group (P=0.002). Mean follow up period was 44.2+/-30.0 months and mean recurrence time between primary operation and recurrence was 26.0+/-22.7 months. CONCLUSIONS: Resection for central type of the recurrent is potentially curative, however treatment failure was common when the recurrence invaded fixed pelvic structure. Our data suggest that local pelvic recurrence should be treated with radical resection as can as possible.
Classification*
;
Follow-Up Studies
;
Humans
;
Prognosis*
;
Rectal Neoplasms*
;
Recurrence*
;
Survival Rate
;
Treatment Failure
4.Incidence and Risk Factors of Rehospitalization with Respiratory Syncytial Virus Infection in Premature Infants.
Eun Ah LEE ; Jea Heon JEONG ; Seung Taek YU ; Chang Woo LEE ; Hyang Suk YOON ; Do Sim PARK ; Yeon Kyun OH
Korean Journal of Pediatrics 2004;47(5):510-514
PURPOSE: We performed this study to evaluate the risk of rehospitalization for respiratory syncytial virus(RSV) infection among premature infants discharged from a neonatal intensive care unit(NICU). METHODS: We performed a retrospective study for rehospitalization for RSV infection and risk factors among premature infants who were admitted to NICU and discharged between May 2001 and April 2003 in Wonkwang University Hospital. RSV detection was utilized by direct fluorescent antibody tests in nasopharyngeal aspirates. We also reviewed various risk factors including gestational age, birth weight, sex, ventilatory care, surfactant administration, chronic lung disease(CLD), siblings in school or kindergarten age, and month of discharge. RESULTS: The rehospitalization rate for RSV infection was 6.6%(26/381) in premature infants and 22.2%(4/18) in premature infants with CLD. The most common season of rehospitalization for RSV infection was between November to January, this was 69.2%(18/26) in premature infants, the same as children: 61.2%(93/152). The risk factors for RSV rehospitalization among premature infants were CLD, siblings in school or kindergarten age and discharge between October to December from NICU. CONCLUSION: The risk for RSV rehospitalization among premature infants from NICU was low. Preterm infants subject to risk factors of CLD, siblings in school or kindergarten age, and discharge between October to December from NICU, were most likely to require hospitalization for RSV disease. In CONCLUSION: Prophylaxis for RSV infection should be considered one month before discharge from NICU in the RSV season between October and December.
Birth Weight
;
Child
;
Gestational Age
;
Hospitalization
;
Humans
;
Incidence*
;
Infant, Newborn
;
Infant, Premature*
;
Intensive Care, Neonatal
;
Lung
;
Respiratory Syncytial Viruses*
;
Retrospective Studies
;
Risk Factors*
;
Seasons
;
Siblings
5.The Origin of Proinflammatory Cytokines in Patients with Idiopathic Dilated Cardiomyopathy.
Hyuk Jae CHANG ; Jaehoon CHUNG ; Byoung Joo CHOI ; Tae Young CHOI ; So Yeon CHOI ; Myeong Ho YOON ; Gyo Seung HWANG ; Joon Han SHIN ; Seung Jea TAHK ; Byung Il William CHOI
Journal of Korean Medical Science 2003;18(6):791-796
Proinflammatory cytokines and their receptors are increased in the peripheral blood of patients with heart failure. We measured cytokines and their receptors in systemic artery (SA), coronary sinus (CS) and infra-renal inferior vena cava (IVC), in order to investigate their origin and influential factors. Thirty patients with idiopathic dilated cardiomyopathy were performed echocardiography at admission, and right heart catheterization after stabilization. Blood was drawn from 3 sites for measurement of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and soluble tumor necrosis factor- receptor (sTNFR) I, II. TNF-alpha at CS (3.25+/-0.34 pg/mL) was higher than those of SA (1.81+/-0.39 pg/mL) and IVC (1.88+/-0.38 pg/mL, p<0.05). IL-6 at CS (18.3+/-3.8 pg/mL) was higher than that of SA (5.8+/-1.2 pg/mL, p<0.01). The levels of sTNFR I, II showed increasing tendency in sequence of SA, IVC and CS. TNF-alpha and sTNFR I, II from all sites were proportional to worsening of functional classes at admission (p<0.05). E/Ea by Doppler study at admission, which reflects left ventricular end-diastolic pressure (LVEDP) was positively correlated with TNF-alpha from SA (R=0.71, p<0.01), CS (R=0.52, p<0.05) and IVC (R=0.46, p<0.05). Thus, elevated LVEDP during decompensation might cause cytokine release from myocardium in patients with idiopathic dilated cardiomyopathy.
Adult
;
Aged
;
Cardiomyopathy, Congestive/*blood/*immunology
;
Female
;
Heart/anatomy & histology
;
Hemodynamic Processes
;
Human
;
Interleukin-6/*blood
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Male
;
Middle Aged
;
Receptors, Tumor Necrosis Factor/*blood
;
Statistics
;
Tumor Necrosis Factor/*metabolism
6.The Angiographic Evaluation of Patency after Coronary Artery Bypass Graft.
Myeong Ki HONG ; Won Heum SHIM ; Yang Soo JANG ; Seung Jea TAHK ; Seung Yun CHO ; Sung Soon KIM ; Woong Ku LEE ; Byung Chul CHANG ; Meyun Shick KANG ; Bum Koo CHO ; Sung Nok HONG ; Pill Whoon HONG
Korean Circulation Journal 1990;20(1):29-36
The patency of graft vessels and their effects on the native coronary circulation were studied by evaluation of 78 graft sites in 35 patients who underwent selective bypass graft angiography among 152 CABG cases at a mean follow-up 12.6 month. The result were as follows ; 1) The overall graft patency rate was 70.5% : 73.8% for left anterior descending artery, 68.4% for left circumflex arterty, 64.7% for right coronary artery. 2) The patency rate of internal mammary artery was 77.8%. 3) In twenty eight patients who underwent native coronary angiography, twelve pateints showed progression of coronary artery disease in grafted vessel and two patients showed progression of coronary artery disease in non-grafted vessel. 4) The treadmill test was performed before and after coronary artery bypass graft in thirteen patients. Among 13 patients, nine patinets showed improved exercise tolerance. 5) The percutaneous transluminal coronary angioplasty were successfully performed for dilating three cases of stenotic vein graft and two cases of left main lesions after CABG and one case of stenotic left internal mammary artery graft.
Angiography
;
Angioplasty, Balloon, Coronary
;
Arteries
;
Coronary Angiography
;
Coronary Artery Bypass*
;
Coronary Artery Disease
;
Coronary Circulation
;
Coronary Vessels*
;
Exercise Test
;
Exercise Tolerance
;
Follow-Up Studies
;
Humans
;
Mammary Arteries
;
Transplants
;
Veins
7.Utilization Trend of Partial Nephrectomy for the Treatment of Renal Cell Carcinoma in Korea: An Multicenter study using URO-PDS.
Seung Jea SHIN ; Hyung Joon KIM ; Kwang Jin KO ; Hyun Hwan SUNG ; Hwang Gyun JEON ; Byong Chang JEONG ; Seong Il SEO ; Hyun Moo LEE ; Han Yong CHOI ; Seong Soo JEON
Korean Journal of Urological Oncology 2015;13(3):128-133
PURPOSE: Partial nephrectomy has a similar oncologic outcome to radical nephrectomy while reducing cardiac and metabolic morbidity. However, previous studies reported that partial nephrectomy had been underutilized. The purpose of this study is to analyze trends in the use of partial nephrectomy in Korea and evaluate which individual factors and hospital factor influenced the operative approach. MATERIALS AND METHODS: Using URO-PDS database, 11560 patients underwent nephrectomy for renal cell carcinoma between 2006 and 2010 were identified. International Classification of Disease (ICD-9) diagnosis codes were applied to target subject of interest. Logistic regression was applied to identify determinants of partial nephrectomy. RESULTS: Over the study period, the proportion of partial nephrectomies has steadily increased from 9.4% in 2006 to 30.4% in 2010 (p<0.001). Deviation of utilization in partial nephrectomy has been observed based on the area (p<0.001) and type of surgery (p<0.001). Individual of younger age, as well as male, were more likely to be treated with partial nephrectomy (p<0.001 for each). Furthermore, Patient treated at hospitals with higher nephrectomy volume were more prone to be treated with partial nephrectomy (p<0.001 for each). CONCLUSIONS: Partial nephrectomies have been increasingly performed over the study period but are still underutilized.
Carcinoma, Renal Cell*
;
Classification
;
Diagnosis
;
Humans
;
Korea*
;
Logistic Models
;
Male
;
Nephrectomy*
8.Predictive factors of prolonged warm ischemic time (> or =30 minutes) during partial nephrectomy under pneumoperitoneum.
Kwang Jin KO ; Don Kyoung CHOI ; Seung Jea SHIN ; Hyun Soo RYOO ; Tae Sun KIM ; Wan SONG ; Hwang Gyun JEON ; Byong Chang JEONG ; Seong Il SEO
Korean Journal of Urology 2015;56(11):742-748
PURPOSE: Current clinical data support a safe warm ischemia time (WIT) limit of 30 minutes during laparoscopic partial nephrectomy (LPN) or robot-assisted partial nephrectomy (RPN). We evaluated independent factors predicting prolonged WIT (more than 30 minutes) after LPN or RPN. MATERIALS AND METHODS: A retrospective data review was performed for 317 consecutive patients who underwent LPN or RPN performed by the same surgeon from October 2007 to May 2013. Patients were divided into two groups: group A was defined as prolonged WIT (> or =30 minutes) and group B as short WIT (<30 minutes). We compared clinical factors between the two groups to evaluate predictors of prolonged WIT. RESULTS: Among 317 consecutive patients, 80 were in the prolonged WIT group. Baseline characteristics were not significantly different between the groups. In the univariable analysis, PADUA (preoperative aspects and dimensions used for an anatomical) score (p=0.001), approach method (transperitoneal or retroperitoneal approach; p<0.001), and surgeon experience (p<0.001) were significantly associated with prolonged WIT. In the multivariable analysis, PADUA score (p=0.032), tumor size (> or =25 mm; odds ratio, 2.98; 95% confidence interval, 1.48-5.96; p=0.002), and surgeon experience (p<0.001) were independent predictors of prolonged WIT. CONCLUSIONS: Surgeon experience, tumor size, and PADUA score predicted prolonged WIT after RPN or LPN. Among these factors, increasing surgical experience with LPN or RPN is the most important factor for preventing prolonged WIT.
Adult
;
Aged
;
Carcinoma, Renal Cell/pathology/*surgery
;
Clinical Competence
;
Female
;
Humans
;
Intraoperative Period
;
Kidney Neoplasms/pathology/*surgery
;
Laparoscopy/methods
;
Male
;
Middle Aged
;
Nephrectomy/*methods
;
Pneumoperitoneum, Artificial/*methods
;
Retrospective Studies
;
Risk Factors
;
Robotic Surgical Procedures/methods
;
Warm Ischemia/*methods
9.Long Spontaneous Remission in Neuromyelitis Optica.
Hyun Gu KANG ; Soo Sung KIM ; Julie JEONG ; Jae Hoon JO ; Myoung Jea YI ; Hak Seung LEE ; Hyun Young PARK ; Hyuk CHANG ; Yo Sik KIM ; Kwang Ho CHO
Journal of the Korean Neurological Association 2011;29(1):52-54
Neuromyelitis optica (NMO) is an inflammatory demyelinating disease of the central nervous system characterized by optic neuritis and longitudinal extensive transverse myelitis. The clinical course can be either polyphasic (relapsing-remitting) or monophasic. The relapsing-remitting course is observed in more than 80% of NMO cases, and relapse generally occurs within 1 year in 60% of patients, and within 3 years in 90%. We report a rare case of long spontaneous remission in untreated NMO.
Central Nervous System
;
Demyelinating Diseases
;
Humans
;
Myelitis, Transverse
;
Neuromyelitis Optica
;
Optic Neuritis
;
Recurrence
;
Remission, Spontaneous
10.Cardiac tamponade complicated by chronic recurrent pancreatitis.
Jea Seung LEE ; You Sun KIM ; Won Cheol CHANG ; Jung Whan LEE ; Jeong Seop MOON ; Ho Kee YUM ; Suk Koo CHOI
Korean Journal of Medicine 2003;65(Suppl 3):S693-S697
Chronic pancreatitis causes a variety of complications such as glucose intolerance, pancreatic pseudocyst and duodenal obstruction. However pericardial effusion is very rarely complicated with chronic pancreatitis and life-threatening. The hypothesis of the development of pleuropericardial effusion in chronic pancreatitis has been variously proposed; fistula formation through esophageal or aortic hiatus, local transfer of pancreatic enzyme. Recently, we experienced a case of pleuropericardial effusion complicated by chronic recurrent pancreatitis causing cardiac tamponade. There was a contrast leakage appearing from the pancreatic duct to the mediastinum in endoscopic retrograde pancreaticography. The transpapillary pancreatic stent insertion led to the disappearance of pleuropericardial effusion on the radiography. We report this unusual manifestation of chronic recurrent pancreatitis with the review of literature.
Cardiac Tamponade*
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Duodenal Obstruction
;
Fistula
;
Glucose Intolerance
;
Mediastinum
;
Pancreatic Ducts
;
Pancreatic Pseudocyst
;
Pancreatitis*
;
Pancreatitis, Chronic
;
Pericardial Effusion
;
Radiography
;
Stents