STATEMENT OF PROBLEM: Unreasonable distal cantilevered implant-supported prosthesis can mask functional problems of reconstruction temporarily, but it can cause serious strain and stress around its supported implant and surrounding alveolar bone. PURPOSE: The purpose of this study was to evaluate strain of implants supporting distal cantilevered fixed prosthesis with two different cantilevered length under distal cantilevered static load. MATERIAL AND METHODS: A partially edentulous mandibular test model was fabricated with auto-polymerizing resin (POLYUROCK; Metalor technologies, Stuttgart, Swiss) and artificial denture teeth (Endura; Shofu inc., Kyoto, Japan). Two implants-supported 5-unit screwretained cantilevered fixed prosthesis was made using standard methods with Type III gold alloy (Harmony C & B55; Ivoclar-vivadent, Liechtenstein, Germany) for superstructure and reinforced hard resin (Tescera; Ivoclar-vivadent, Liechtenstein, Germany) for occlusal material. Two strain gauges (KFG-1-120-C1-11L1M2R; KYOWA electronic instruments, Tokyo, Japan) were then attached to the mesial and the distal surface of each standard abutment with adhesive (M-bond 200; Tokuyama, Tokyo, Japan). Total four strain gauges were attached to test model and connected to dynamic signal conditioning strain amplifier (CTA1000; Curiotech inc., Paju, Korea). The stepped 20-100 N in 25 N increments, cantilevered static load 8mm apart (Group I) or 16mm apart (Group II), were applied using digital push-pull gauge (Push-Pull Scale & Digital Force Gauge, Axis inc., Seoul, Korea). Each step was performed ten times and every strain signal was monitored and recorded. RESULTS: In case of Group I, the strain values were surveyed by 80.7 ~ 353.8 micrometer/m in Ch1, 7.5 ~ 47.9 micrometer/m in Ch2, 45.7 ~ 278.6 micrometer/m in Ch3 and -212.2 ~ -718.7 micrometer/m in Ch4 depending on increasing cantilevered static load. On the other hand, the strain values of Group II were surveyed by 149.9 ~ 612.8 micrometer/m in Ch1, 26.0 ~ 168.5 micrometer/m in Ch2, 114.3 ~ 632.3 micrometer/m in Ch3, and -323.2 ~ -894.7 micrometer/m in Ch4. CONCLUSION: A comparative statistical analysis using paired sample t-test about Group I Vs Group II under distal cantilevered load shows that there are statistical significant differences for all 4 channels (P<0.05).
Adhesives ; Alloys ; Axis, Cervical Vertebra ; Dentures ; Hand ; Liechtenstein ; Masks ; Prostheses and Implants* ; Seoul ; Tooth

BACKGROUND: Post-transfusion hepatitis B remains a risk for recipients of HBsAg negative bloods in Korea. The usefulness of anti-HBc screening for blood donors to reduce the risk of HBV transmission was evaluated in this study using LG Anti-HBc and LG Anti-HBs ELISA (LG Chemicals, Seoul, Korea) and HBV nucleic acid amplification test. METHOD: Sera from 2,274 HBsAg-negative blood donors were tested of anti-HBc and anti-HBs by LG Anti-HBc and LG Anti-HBs ELISA, respectively. Using 260 samples from HBsAg-negative blood donors and 62 FANA-positive samples, reactivity to LG Anti-HBc ELISA were compared with COBAS CORE Anti-HBc EIA (Roche Diagnostics, Basel, Switzerland). The precision of LG Anti-HBc was also tested. The nucleic acid amplification of 97 primary pools prepared from 2,274 samples was carried out, and then HBV presence was confirmed in individual samples. RESULT: Of 2,274 HBsAg-negative blood donors, 531 (23.4%) were positive for anti-HBc and 32 (1.4%) were anti-HBc positive/ anti-HBs negative. The concordance rate of LG Anti-HBc ELISA and COBAS was 97.8% (315/322). The intra-run and inter-run coefficient of variation was 4.7-10.2% and 2.5-11.4%, respectively. Thirteen pools showed initial positive in HBV PCR, but seven pools (53.8%) were finally found to be false positive. Of six true positive pools, seven samples were confirmed to have HBV DNA. The HBV detection rate was 6.3% (2/32) among donors whose results were anti-HBc positive/ anti-HBs negative. CONCLUSION: Among screen-negative blood donors, 6.3% of donors whose seroreactivity was anti-HBc positive/ anti-HBs negative were positive for HBV by nucleic acid amplification test, while donors showing such seroreactivity were only 1.4%. It is suggested that an introduction of anti-HBc and anti-HBs testing in Korean Blood Donation program be efficient to attain safety from HBV transmission.
Blood Donors* ; DNA ; Enzyme-Linked Immunosorbent Assay* ; Hepatitis B ; Hepatitis B Surface Antigens ; Humans ; Korea ; Mass Screening* ; Nucleic Acid Amplification Techniques* ; Polymerase Chain Reaction ; Seoul ; Tissue Donors

PURPOSE: This study investigated the strain of implants using a chewing simulator with strain gauges in mandibular implant-supported fixed prostheses under various dynamic loads. MATERIALS AND METHODS: Three implant-supported 5-unit fixed prostheses were fabricated with three different occlusion types (Group I: Canine protected occlusion, Group II: Unilaterally balanced occlusion, Group III: Bilaterally balanced occlusion). Two strain gauges were attached to each implant abutment. The programmed dynamic loads (0 - 300 N) were applied using a chewing simulator (MTS 858 Mini Bionix II systems, MTS systems corp., Minn, USA) and the strains were monitored. The statistical analyses were performed using the paired t-test and the ANOVA. RESULTS: The mean strain values (MSV) for the working sides were 151.83 microepsilon, 176.23 microepsilon, and 131.07 microepsilon for Group I, Group II, and Group III, respectively. There was a significant difference between Group II and Group III (P < .05). Also, the MSV for non-working side were 58.29 microepsilon, 72.64 microepsilon, and 98.93 microepsilon for Group I, Group II, and Group III, respectively. One was significantly different from the others with a 95% confidence interval (P < .05). CONCLUSION: The MSV for the working side of Groups I and II were significantly different from that for the non-working side (Group I: t = 7.58, Group II: t = 6.25). The MSV for the working side of Group II showed significantly larger than that of Group III (P < .01). Lastly, the MSV for the non-working side of Group III showed significantly larger than those of Group I or Group II (P < .01).
Mastication ; Prostheses and Implants ; Sprains and Strains

OBJECTIVE: To evaluate the perinatal outcomes and maternal complications associated with triplet pregnancies. METHODS: Medical records of consecutive triplet pregnancies delivered in ( )( )Hospital from 1997 to 2005 were reviewed for maternal and neonatal outcomes. Pregnancies associated with lethal congenital anomalies or the case that being delivered before 20 weeks of gestation were excluded. Neonatal outcomes included respiratory distress syndrome, retinopathy of prematurity, necrotizing enterocolitis, intraventricular hemorrhage and low Apgar scores, congenital anomaly and so on. Maternal outcomes included preeclampsia, preterm delivery, anemia and blood transfusion and so on. RESULTS: The mean gestational age at delivery was 31.5+/-4.1 weeks, and the mean birth weight for triplets was 1,654.4+/-578.1 g. 31 of total 39 neonates (79.5%) were admitted to the neonatal intensive care unit, and 9 neonates (23.1%) received mechanical ventilator care as well. Neonatal death occurred in 6 of 39 neonates (15.4%). Congenital anomaly was seen in 3 of 39 neonates (7.7%). Hyperbilirubinemia developed in 16 of 39 neonates (44.4%). Respiratory distress syndrome developed in 3 of 39 neonates (7.7%). The most common maternal complication was preterm labor (76.9%), followed by anemia (46.1%), preterm premature rupture of membrane (30.8%) and blood transfusion (7.7%). Five patients (5/13, 38.5%) received tocolytic therapy. CONCLUSION: The main cause of neonatal death in triplet pregnancies is the respiratory distress syndrome in extreme preterm delivery. The most common neonatal morbidities are hyperbilirubinemia and apnea of prematurity. There is no difference in neonatal outcomes according to birth order. The most common maternal complications are preterm delivery and anemia. The adverse outcomes of triplet pregnancies are mainly due to preterm delivery.
Anemia ; Apnea ; Birth Order ; Birth Weight ; Blood Transfusion ; Enterocolitis, Necrotizing ; Female ; Gestational Age ; Hemorrhage ; Humans ; Hyperbilirubinemia ; Infant, Newborn ; Intensive Care, Neonatal ; Medical Records ; Membranes ; Obstetric Labor, Premature ; Pre-Eclampsia ; Pregnancy ; Pregnancy, Triplet* ; Retinopathy of Prematurity ; Rupture ; Tocolysis ; Triplets* ; Ventilators, Mechanical

OBJECTIVE: To evaluate the perinatal outcomes and maternal complications associated with triplet pregnancies. METHODS: Medical records of consecutive triplet pregnancies delivered in ( )( )Hospital from 1997 to 2005 were reviewed for maternal and neonatal outcomes. Pregnancies associated with lethal congenital anomalies or the case that being delivered before 20 weeks of gestation were excluded. Neonatal outcomes included respiratory distress syndrome, retinopathy of prematurity, necrotizing enterocolitis, intraventricular hemorrhage and low Apgar scores, congenital anomaly and so on. Maternal outcomes included preeclampsia, preterm delivery, anemia and blood transfusion and so on. RESULTS: The mean gestational age at delivery was 31.5+/-4.1 weeks, and the mean birth weight for triplets was 1,654.4+/-578.1 g. 31 of total 39 neonates (79.5%) were admitted to the neonatal intensive care unit, and 9 neonates (23.1%) received mechanical ventilator care as well. Neonatal death occurred in 6 of 39 neonates (15.4%). Congenital anomaly was seen in 3 of 39 neonates (7.7%). Hyperbilirubinemia developed in 16 of 39 neonates (44.4%). Respiratory distress syndrome developed in 3 of 39 neonates (7.7%). The most common maternal complication was preterm labor (76.9%), followed by anemia (46.1%), preterm premature rupture of membrane (30.8%) and blood transfusion (7.7%). Five patients (5/13, 38.5%) received tocolytic therapy. CONCLUSION: The main cause of neonatal death in triplet pregnancies is the respiratory distress syndrome in extreme preterm delivery. The most common neonatal morbidities are hyperbilirubinemia and apnea of prematurity. There is no difference in neonatal outcomes according to birth order. The most common maternal complications are preterm delivery and anemia. The adverse outcomes of triplet pregnancies are mainly due to preterm delivery.
Anemia ; Apnea ; Birth Order ; Birth Weight ; Blood Transfusion ; Enterocolitis, Necrotizing ; Female ; Gestational Age ; Hemorrhage ; Humans ; Hyperbilirubinemia ; Infant, Newborn ; Intensive Care, Neonatal ; Medical Records ; Membranes ; Obstetric Labor, Premature ; Pre-Eclampsia ; Pregnancy ; Pregnancy, Triplet* ; Retinopathy of Prematurity ; Rupture ; Tocolysis ; Triplets* ; Ventilators, Mechanical

OBJECTIVE: Because women with Eisenmenger syndrome are counseled strongly not to conceive, pregnancy cases with Eisenmenger syndrome are rare in clinical situation. We performed this study to analyze pregnancies at second and third trimester complicated by Eisenmenger syndrome and to evaluate changes during pregnancy and their outcomes. METHODS: Medical records were reviewed retrospectively for Eisenmenger syndrome patients who delivered at second and third trimester at Seoul National University Hospital from January 1989 to October 2005. RESULTS: Among the total of 6 pregnant women, 4 women delivered after 34 weeks and 2 women had therapeutic termination during second trimester. All 4 women who delivered after 34 weeks were categorized as class III by New York Heart Association classification. Maternal mortality rate was 33% (2 of 6 cases). All mortality cases were patients who delivered after 34 weeks. All neonates were small for gestational age with no neonatal death. There was no neonatal morbidity except one case of congenital atrial septal defect. CONCLUSION: Maternal mortality occurred in half of the women who continued their pregnancy beyond second trimester. We think that pregnancy should be still discouraged in patients with Eisenmenger syndrome and that therapeutic abortion should be offered in early pregnancy period.
Abortion, Therapeutic ; Classification ; Eisenmenger Complex* ; Female ; Gestational Age ; Heart ; Heart Septal Defects, Atrial ; Humans ; Infant, Newborn ; Maternal Mortality ; Medical Records ; Mortality ; Pregnancy Outcome ; Pregnancy Trimester, Second ; Pregnancy Trimester, Third* ; Pregnancy* ; Pregnant Women ; Retrospective Studies ; Seoul

BACKGROUND: The aim of this study was to investigate the prevalence, clinical and laboratory findings of hereditary hemolytic anemia (HHA) in Korea from 1997 to 2006 and to develop the appropriate diagnostic approach for HHA. METHODS: By the use of questionnaires, information on the clinical and laboratory findings ofHHA diagnosed from 1997 to 2006 in Korea was collected and analyzed retrospectively. A total of 431 cases were enrolled in this study from 46 departments of 35 hospitals. RESULTS: The overall frequency of HHA did not change through the 10-year period for pediatrics but did show an increasing tendency for internal medicine. The overall male to female sex ratio did not show sex predominance (1.17:1), but a significant male predominance with a ratio of 1.49:1 was seen for pediatrics while a significant female predominance with a ratio of 1:1.97 was seen forinternal medicine. Of the total cases, 74.2% (282/431) were diagnosed before the age of 15 years. The etiologies of HHA were classified as red cell membrane defects, hemoglobinopathies, red cell enzyme deficiencies and unknown causes. There were 382 cases (88.6%) of red cell membrane defects with 376 cases (87.2%) of hereditary spherocytosis and 6 cases (1.4%) of hereditary elliptocytosis, 20 cases (4.6%) of hemoglobinopathies with 18 cases (4.2%) of beta-thalassemia, a case (0.2%) of alpha-thalassemia and a case (0.2%) of Hemoglobin Madrid, 7 cases (1.6%) of red cell enzyme deficiencies with 5 cases (1.2%) of glucose-6- phosphate dehydrogenase (G-6-PD) deficiency, a case (0.2%) of pyruvate kinase (PK) deficiency and a case (0.2%) of enolase deficiency, and 22 cases (5.1%) of unknown causes. The most common chief complaint in pediatric patients was pallor and that in adult patients was jaundice. In the red cell membrane defect group of patients, the level of hemoglobin was significantly higher than in adult patients. The mean corpuscular volume, mean corpuscular hemoglobin, corrected reticulocyte count, total and indirect bilirubin level and lactate dehydrogenase levels in the hemoglobinopathy group of patients were significantly lower than the values in the red cell membrane defect group of patients. The mean concentration of G-6-PD was 0.8+/-0.7U/1012RBC in the G-6-PD deficient patients, PK was 1.7U/1010 RBC in the PK deficient patient, and the level of enolase was 0.04U/g of Hb in the enolase deficient patient. CONCLUSION: The most prevalent cause of HHA in Korea during 1997 to 2006 was hereditary spherocytosis, but HHA by other causes such as hemoglobinopathy and red cell enzyme deficiency gradually increased with the development of molecular diagnostic methods and increasing general interest. However, the etiologies of HHA need to be pursued further in 5.1% of the patients. An systematic standard diagnostic approach is needed in a nationwide prospective study for correct diagnoses and appropriate management of HHA.
Adult ; alpha-Thalassemia ; Anemia, Hemolytic, Congenital* ; beta-Thalassemia ; Bilirubin ; Cell Membrane ; Diagnosis ; Elliptocytosis, Hereditary ; Erythrocyte Indices ; Female ; Hemoglobinopathies ; Humans ; Internal Medicine ; Jaundice ; Korea* ; L-Lactate Dehydrogenase ; Male ; Oxidoreductases ; Pallor ; Pathology, Molecular ; Pediatrics ; Phosphopyruvate Hydratase ; Prevalence ; Pyruvate Kinase ; Reticulocyte Count ; Retrospective Studies* ; Sex Ratio ; Surveys and Questionnaires