PURPOSE: Manufacturing with AM (Additive manufacturing) technique has many advantages; but, due to insufficient study in the area, it is not being widely used in the general clinic. In this study, differences of flexural strength among various materials of 3 unit fixed dental prosthesis were analyzed. MATERIALS AND METHODS: A metal jig for specimens that had a 3-unit-fixed dental prosthesis figure were fabricated. The jigs were made appropriately to the specifications of the specimens. Three different kinds of materials of specimens which were NC (mathacrylic esther based), DP-1 (Bisphenol A epoxy acrylate type oligomer based), and DT-1 (urethane acrylate based) were printed with DLP machine. Five specimens for each kind of material were printed with an angle of 30° from the horizontal surface. The specimens were placed on the jig and the flexural strength was measured and recorded using Universal testing machine. The recorded data was analyzed in SPSS using One-way ANOVA and Tukey HSD to determine the significance of the differences of flexural strength among the groups. RESULTS: The flexural strengths of each group were the followings: NC, 1119 ± 305 N; DP-1, 619 ± 150 N; DT-1, 413 ± 65 N. Using One-way ANOVA and Tukey Honestly Significant Difference test, significant difference was found between NC and the other groups (P < 0.05), but there was no significant difference between DP-1 and DT-1 (P > 0.05). CONCLUSION: Higher flexural strength was shown in 3-unit-fixed dental prosthesis that were 3D printed using a DLP machine with NC material.
Dental Prosthesis ; Printing, Three-Dimensional

OBJECTIVE: This study aimed to (1) evaluate the effects of maxillary second and third molar eruption status on the distalization of first molars with a modified palatal anchorage plate (MPAP), and (2) compare the results to the outcomes of the use of a pendulum and that of a headgear using three-dimensional finite element analysis. METHODS: Three eruption stages were established: an erupting second molar at the cervical one-third of the first molar root (Stage 1), a fully erupted second molar (Stage 2), and an erupting third molar at the cervical one-third of the second molar root (Stage 3). Retraction forces were applied via three anchorage appliance models: an MPAP with bracket and archwire, a bone-anchored pendulum appliance, and cervical-pull headgear. RESULTS: An MPAP showed greater root movement of the first molar than crown movement, and this was more noticeable in Stages 2 and 3. With the other devices, the first molar showed distal tipping. Transversely, the first molar had mesial-out rotation with headgear and mesial-in rotation with the other devices. Vertically, the first molar was intruded with an MPAP, and extruded with the other appliances. CONCLUSIONS: The second molar eruption stage had an effect on molar distalization, but the third molar follicle had no effect. The application of an MPAP may be an effective treatment option for maxillary molar distalization.
Crowns ; Finite Element Analysis* ; Molar* ; Molar, Third

BACKGROUND/AIMS: Several recent studies have reported that the early use of infliximab (IFX) improves the prognosis of Crohn's disease (CD). However, no data are available from Asian populations, as the forementioned studies have all been conducted in Western countries. The aim of the current study was to evaluate the impact of early use of IFX on the prognosis of Korean patients with CD. METHODS: Patients with a diagnosis of CD established between July 1987 and January 2012 were investigated in 12 university hospitals in Korea. Because insurance coverage for IFX treatment began in August 2005, patients were assigned to either of 2 groups based on diagnosis date. The first group included patients diagnosed from July 1987 to December 2005, and the second from January 2006 to January 2012. We compared the cumulative probabilities of operation and reoperation between the two groups using the Kaplan-Meier method and a log-rank test. RESULTS: Of the 721 patients investigated, 443 (61.4%) comprized the second group. Although the cumulative probabilities of immunosuppressant (P<0.001) and IFX use (P<0.001) after diagnosis were significantly higher in the second group, there were no significant differences in cumulative probabilities of operation (P=0.905) or reoperation (P=0.418) between two groups. CONCLUSIONS: The early use of IFX did not reduce CD-related surgery requirements in Korean patients with CD. These study results suggest that the early use of IFX may have little impact on the clinical outcome of CD in Korean patients in the setting of a conventional step-up algorithm.
Asian Continental Ancestry Group ; Crohn Disease* ; Diagnosis ; Hospitals, University ; Humans ; Infliximab ; Insurance Coverage ; Korea ; Prognosis ; Reoperation

PURPOSE: An insufficient functioning nephron mass might fail to meet the metabolic demands of the recipient and lead to hyperfiltration. This hyperfiltration damage also increase allograft failure rates. During the preoperative evaluation of a potential kidney donor, it is important to estimate the renal function of donated kidney compared with the metabolic needs of the recipient. METHODS: The functional ratio of each kidney was measured using technetium-99m diethylenetriaminepentaacetic acid. The serum creatinine (Scr, mg/dL) and estimated creatinine clearance (Ccr, mL/min/1.73m2) using the Cockcroft-Gault formula were measured and calculated in 82 donors. We excluded recipients who had an episode of rejection, and followed all recipients for more than 12 months posttransplantation. RESULTS: The average functional proportion of the donated kidney was 50.5%+/-4.7% of the total Ccr 83.4+/-18.3 of donors. The Scr of recipients at 1,3,6 and 9months posttransplantation were significantly (P<.05) correlated with the fractional Ccr of thedonated kidney; however Scr at 1 year was not correlated (P=.307). Furth-ermore the Ccr of the recipient at 1, 3, and 6months post transplantation were significantly (P<.05) correlated with fractional Ccr ofthe donated kidney; however the Ccr at 9months and 1 year were not correlated (P=.094 and.141, respectively). CONCLUSION: The Scr and Ccr of recipients within 6 months after transplantation may depend on the functional mass of the donated kidney, which should be estimated prior to kidney donation and compared with the metabolic demands of the potential recipient.
Allografts ; Creatinine* ; Humans ; Kidney Transplantation ; Kidney* ; Living Donors* ; Nephrons ; Tissue Donors ; Transplants*

OBJECTIVE: The purpose of our study was to describe acute necrotizing encephalopathy in Korean infants and children, and we sought to evaluate the prognostic factors. MATERIALS AND METHODS: Acute necrotizing encephalopathy was diagnosed in 14 Korean infants and children. We retrospectively analyzed the neuroimaging findings including the follow-up changes. The clinical course of the disease was graded, and we evaluated prognostic factors including age, serum level of the aminotransferase, hemorrhage, and localized atrophy of the brain. RESULTS: This encephalopathy predominantly affected the bilateral thalami (n=14), pons (n=12), and midbrain (n=10) in a symmetrical pattern. Hemorrhage was observed in eight patients (57%). On the follow-up images (n=12), the brain lesions were reduced in extent for all patients, and generalized atrophy was seen in six patients. Localized tissue loss was observed in five patients and a complete resolution occurred for one patient. All the patients survived and two recovered completely; mild (n=6) to severe (n=6) neurological deficits persisted in the remaining 12 patients. The significant prognostic factors identified in this study were the presence of hemorrhage (p = 0.009) and localized atrophy (p = 0.015). CONCLUSION: Acute necrotizing encephalopathy in Korean patients showed the characteristic patterns of the post-infectious encephalopathy as described in the literature. The high survival rate and the relatively favorable clinical course observed for the present study suggest a more diverse spectrum of disease severity than was previously described. The presence of hemorrhage and localized tissue loss on MR images may suggest a poor prognosis.
Brain/pathology ; Child ; Child, Preschool ; Female ; Humans ; Infant ; Korea ; Leukoencephalitis, Acute Hemorrhagic/complications/*pathology ; *Magnetic Resonance Imaging ; Male ; Prognosis ; Retrospective Studies

Branch retinal vein occlusion(BRVO) is the most frequent entity of retinal vascular abnormality following diabetic retinopathy; a review of diagnosis for all our new outpatients verifies this, Sudden loss of visual acuity occur in the vast majority of BRVO patients. Other complications are macular edema, capillary nonperfusion, neovascularization, vitreous hemorrhage and so on. We did a clinical analysis of 71 patients with BRVO(71 eyes), who were considered to be treated with laser photocoagulation to prevent vitreous hemorrhage. We confirmed the fact that laser photocoagulation could prevent vitreous hemorrhage to a significant degree, but we were unable to demonstrate any statistical correlation between the occurrence of vitreous hemorrhage and the time of laser photocoagulation.
Argon* ; Capillaries ; Diabetic Retinopathy ; Diagnosis ; Humans ; Light Coagulation* ; Macular Edema ; Outpatients ; Retinal Vein ; Retinaldehyde ; Visual Acuity ; Vitreous Hemorrhage*

PURPOSE:To investigate the changes of abnormal signal intensity of liver infarction in scheduled intervals after ligation of portal vein in rabbit livers with histopathologic correlation. MATERIALS AND METHODS:Liver infarction were induced by selective ligation of the posterior branch of right portal vein in 12 rabbits. T1- and T2-weighted MRI at 2.0T with spin-echo techniques as well as contrastenhanced Tl-weighted MRI with Gd-DTPA(0.1 mmol/kg) were performed 3 hours, 6 hours, 1 day, 3 days, 1 week, and 2 weeks after ligation using two rabbits at each interval. Histopathologic specimens were prepared from six removed livers for comparing the MR findings with the histopathologic findings. The other six rabbits were sectioned transversely in frozen state for comparing MR findings with the macroscopic findings of pathologic areas of the liver. RESULTS: The signal intensity of pathologic hepatic segment showed more hyperintense signal than that of normal segments of the liver on TI-, proton density-, and T2-weighted MR images at every interval after ligation, except both T2WI of 3 hours interval and one T1WI of 2 weeks interval. Main histopathologic findings 3 hours, 6 hours, 1 day, 3 days, and 1 week after ligation were congestion, hemorrhage with necrosis, coagulation necrosis, complete necrosis, and necrosis with scar tissues, respectively. Microscopic specimens with Prussian blue stain 6 hours, and 1 week after ligation showed bluish hue indicating the existence of methemoglobin, and blue particles in giant cells and monocytes indicating engulfing hemosiderin, respectively. CONCLUSION: Changes of the signal intensities on sequential MR images of acutely induced hemorrhagic liver infarction might be due to the rapid oxidative denaturation of hemoglobin in hemorrhages and high signal intensity on Tl-weighted images from the hyperacute stage of a hemorrhagic liver infarction could be due to methemoglobin. Therefore, acutely induced hemorrhagic liver infarction should be included in the differential diagnoses of the hyperintense liver lesions on Tl-weighted images.
Cicatrix ; Diagnosis, Differential ; Estrogens, Conjugated (USP) ; Giant Cells ; Hemorrhage ; Hemosiderin ; Infarction ; Ligation* ; Liver* ; Magnetic Resonance Imaging* ; Methemoglobin ; Monocytes ; Necrosis ; Portal Vein* ; Protons ; Rabbits*

PURPOSE: To describe the radiological differences between tuberculous(TBB) and non-tuberculous bronchiectasis(NTBB). MATERIALS AND METHODS: Chest radiographs(n=62), bronchograms(n=18), and CT scans(n=52) of 37 patients with TBB and 25 patients with NTBB were reviewed retrospectively. Diagnostic basis for TBB were positive sputum AFB with or without history of anti-tuberculous chemotherapy(n=35), and radiological findings of pulmonary tuberculosis (n=2). Four of NTBB had a history of severe respiratory tract infection in childhood. RESULTS: Air-fluid levels on chest radiographs were seen in 2% of TBB, and 20% of NTBB. On bronchograms, all patients with TBB had combined focal bronchostenosis, whereas patients with NTBB had tubular(50%), cystic(17%), or mixed(33%) pattern of dilatation without stenosis. On CT scans, focal emphysema was seen in 86% of the patients with TBB, and 38% of the patients with NTBB. Peribronchiolar infiltration were seen in 78% and 44% of patients with TBB and NTBB, retrospectively. CONCLUSION: Basic radiological difference between TBB and NTBB was that the former had coexistent sten.
Bronchiectasis* ; Constriction, Pathologic ; Dilatation ; Humans ; Pulmonary Emphysema ; Radiography, Thoracic ; Respiratory Tract Infections ; Retrospective Studies ; Sputum ; Thorax ; Tomography, X-Ray Computed ; Tuberculosis, Pulmonary

PURPOSE: To elucidate high-resolution CT(HRCT) findings and their pathologic basis in pulmonary oil embolism induced by LipiodoI-Adriamycin emulsion. MATERIALS AND METHODS: Pulmonary oil embolism was induced by infusing LipiodoI-Adriamycin emulsion through a peripheral vein in twelve Yorkshire pigs. Serial HRCT scans were performed on 2rid, 4th, 7th, 14th, and 28th day after the procedure. The pigs were sacrificed immediately after HRCT and histologic specimens were prepared in the same plane and level with HRCT. RESULTS: The basic pathology was reversible hemorrhagic edema of the lung. On HRCT, intraalveolar hemorrhage and edema in the acute stage manifested as ground-glass opacity or air-space consolidation of the whole secondary Iobule. The lesions were predominantly distributed over the dependent posterior lung fields because the specific gravity of Lipiodol is 1.28. Interlobular septal thickening due to edematous fluid collection was also associated. With the elapse of time, the extent and severity of the acute lesions resolved and, sometimes, changed into small nodular opacities. Pulmonary opacity was most severe on the post-embolization 2nd day and completely resolved within 2 weeks. CONCLUSION: Pulmonary embolization of LipiodoI-Adriamycin emulsion causes reversible hemorrhagic edema of the lung and Lipiodol toxicity seems to play a major role. HRCT findings of pulmonary oil embolism are quite different from those of pneumonia and pulmonary metastasis, which suggests the possibility of clincal application.
Edema ; Embolism* ; Ethiodized Oil ; Hemorrhage ; Lung ; Neoplasm Metastasis ; Pathology ; Pneumonia ; Specific Gravity ; Swine ; Veins

Balloon pulnounary valvuloplasty is an established method in the treatment of congenital valvular pulmonary stenosis. Balloon valvuloplasty was performed by using one or two balloons in a total of 19 mongrel dogs. Cross sectional area ratio ranging 145-406% was used to compare the relative sizes of the pulmonary annulus the balloon Hemodynamic changes and cardiac damages in single and double balloon groups were analyzed. Survival time of double balloon group was longer than that of single balloon group(P<0.05). Increment of the right ven?dular systolic pressure in single balloon group (mean 38 mmHg) was greater than that in double balloon group (mean 18 mmHg) (p<0.05). Decrement of the femoral arterial pressure in single balloon group (mean 87 mmHg) was greater than in double balloon group (mean 41 mmHg) (p<0.05). The locations of trauma were mainly the right ventricular free wall, the main pulmonary artery, the anterior leaflet of the pulmonary valve and in a less degree, anterior wall of the right atrium, the right ventricular outflow tract and the left pulmonary artery in the order of frequency. There were no significant differences in cardiac damages between single and double balloon groups (P>0.05). Major microscopic findings were sloughing of the endotheliu, fibrin deposition, hemorrhage, localized myocardial infarction and so on. In conclusion, double balloon pulmonary valvuloplasty is superior to single balloon technique in survival time and hemodynamics. Therefore, double, balloon technique is recommended for the pulmonary valvuloplasty.
Animals ; Arterial Pressure ; Balloon Valvuloplasty ; Blood Pressure ; Catheters* ; Dogs ; Fibrin ; Heart Atria ; Hemodynamics ; Hemorrhage ; Methods ; Myocardial Infarction ; Pulmonary Artery ; Pulmonary Valve ; Pulmonary Valve Stenosis