1.Accuracy of different electronic torque drivers: A comparative evaluation
Byeong Dae KO ; KeunBaDa SON ; Seok Hyon KANG ; Kyu Bok LEE
The Journal of Advanced Prosthodontics 2019;11(6):350-357
PURPOSE: This study aims to evaluate the loosening torque on the implant fixture, and to assess the accuracy of difference electronic torque drivers.MATERIALS AND METHODS: Three electronic torque drivers were used to measure the loosening torque on the implant system (AnyOne; MegaGen). The implant fixtures were divided among the 3 electronic torque driver types (W&H, SAESHIN, and NSK group) and 9 for each group. The screws were fastened at the implant fixture by three electronic torque drivers using the tightening torques recommended by the manufacturers of the drivers. After 10 minutes, the screws were again fastened at the implant fixture with equal torque. Then, the loosening torques were measured with an MGT12 torque gauge (MARK-10, Inc.). This measurement procedure was repeated 10 times under loosening torques of 15 Ncm, 25 Ncm, and 35 Ncm. In the statistical analysis, all values of loosening torque were analyzed with the one-way ANOVA and Kruskal-Wallis test (α=.05) for comparative evaluation.RESULTS: There were significant inter-group differences at loosening torques of 15 Ncm and 25 Ncm (P<.05). The accuracy of the NSK driver was the highest, followed by SAESHIN and W&H. There was no significant difference between NSK and W&H at 35 Ncm (P>.05). The SAESHIN driver showed the closest loosening torque at 35 Ncm.CONCLUSION: The most accurate loosening torques were SAESHIN at 35 Ncm, and NSK at 15 Ncm and 25 Ncm. Since the loosening torque may vary depending on the tightening torques and electronic torque drivers, periodic calibration of the electronic torque driver is recommended.
Calibration
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Torque
2.Minimum Specimen Volume Analysis of ABO/RhD Typing and Unexpected Antibody Screening Using an Automated Immunohematology System DAYmate S.
Tae Yeul KIM ; Dong Woo SHIN ; Byeong Hui SON ; Ji Sang KANG ; Yousun CHUNG ; Dae Hyun KO ; Yun Ji HONG ; Hyungsuk KIM ; Kyoung Un PARK ; Kyou Sup HAN
Korean Journal of Blood Transfusion 2018;29(2):159-170
BACKGROUND: Phlebotomy performed for laboratory testing has the potential to cause anemia in newborns and infants. This study investigated the minimum specimen volume required for an automated immunohematology analyzer DAYmate S. METHODS: Three combinations of tubes were evaluated: I. 6 mL EDTA tube, II. 0.5 mL microtainer (on top of 3 mL EDTA tube), and III. 1 mL sample cup (on top of 6 mL EDTA tube). ABO/RhD cell typing was done using centrifuged red cells; unexpected antibody screening was carried out using plasma, and Type & Screening was conducted using whole blood samples. The lowest specimen volume capable of performing 10 repetitive tests without errors was investigated. RESULTS: ABO/RhD cell typing could be performed from I. 30 μL, II. 25 μL, and III. 25 μL. Unexpected antibody screening could be performed from I. 170 μL, II. 150 μL, and III. 140 μL. According to the hematocrit levels, Type & Screening could be performed from 30%, I&III 650 μL, II. 800 μL; 40%, I&III 650 μL, II. 900 μL; and 50%, I&III 1,000 μL, II. Testing using specimen volumes below 1,000 μL was difficult. CONCLUSION: By separating red cells and plasma, pre-transfusion testing of ABO/RhD cell typing and unexpected antibody screening could be conducted with very small specimen volumes using DAYmate S compared to Type & Screening using whole blood. The application of small-sized sample tubes was more competitive and this is expected to be very useful for preventing iatrogenic anemia in neonates and infants less than 4 months old.
Anemia
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Edetic Acid
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Hematocrit
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Humans
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Infant
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Infant, Newborn
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Mass Screening*
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Phlebotomy
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Plasma
3.In vitro wear behavior between enamel cusp and three aesthetic restorative materials: Zirconia, porcelain, and composite resin
Yong Seok JANG ; Thuy Duong Thi NGUYEN ; Young Han KO ; Dae Woo LEE ; Byeong Ju BAIK ; Min Ho LEE ; Tae Sung BAE
The Journal of Advanced Prosthodontics 2019;11(1):7-15
PURPOSE: The aim of this study was to identify the effects of three aesthetic restorative materials on the wear between tooth and restoration by a pin-on-disk manner. MATERIALS AND METHODS: Six aesthetic restorative materials were used to prepare disk specimens for wear test, which were Lava Zirconia as zirconia group, Vintage MP and Cerabien ZR as veneering porcelain group, Gradia Direct microhybrid composite containing prepolymerized fillers, Filtek Z250 microhybrid composite containing zirconia glass and colloidal silica particles, and Filtek Z350 nanocomposite as composite resin group. Vertical loss of the worn cusp, change of the surface roughness of the restoration materials, and the surface topography were investigated after wear test under 9.8-N contact load. RESULTS: The porcelain groups (Vintage MP and Cerabien ZR) caused the largest vertical loss of teeth when compared with those of the composite resin and zirconia groups, and Filtek Z250 microhybrid composite results in the second-largest vertical loss of teeth. The surface of Filtek Z350 nanocomposite was deeply worn out, but visible wear on the surface of the zirconia and Gradia Direct microhybrid composite was not observed. When the zirconia surface was roughened by sand-blasting, vertical loss of teeth considerably increased when compared with that in the case of fine polished zirconia. CONCLUSION: It was identified that microhybrid composite resin containing a prepolymerized filler and zirconia with reduced surface roughness by polishing were the most desirable restorative materials among the tested materials to prevent the two-body wear between aesthetic restorative material and tooth.
Colloids
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Dental Enamel
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Dental Porcelain
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Glass
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In Vitro Techniques
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Nanocomposites
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Silicon Dioxide
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Tooth
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Tooth Abrasion
4.A Phase 3 Randomized Clinical Trial to Compare Efficacy and Safety between Combination Therapy and Monotherapy in Elderly Patients with Advanced Gastric Cancer (KCSG ST13-10)
Keun-Wook LEE ; Dae Young ZANG ; Min-Hee RYU ; Hye Sook HAN ; Ki Hyang KIM ; Mi-Jung KIM ; Sung Ae KOH ; Sung Sook LEE ; Dong-Hoe KOO ; Yoon Ho KO ; Byeong Seok SOHN ; Jin Won KIM ; Jin Hyun PARK ; Byung-Ho NAM ; In Sil CHOI
Cancer Research and Treatment 2023;55(4):1250-1260
Purpose:
This study evaluated whether combination therapy is more effective than monotherapy in elderly patients with metastatic or recurrent gastric cancer (MRGC) as first-line chemotherapy.
Materials and Methods:
Elderly (≥ 70 years) chemo-naïve patients with MRGC were allocated to receive either combination therapy (group A: 5-fluorouracil [5-FU]/oxaliplatin, capecitabine/oxaliplatin, capecitabine/cisplatin, or S-1/cisplatin) or monotherapy (group B: 5-FU, capecitabine, or S-1). In group A, starting doses were 80% of standard doses, and they could be escalated to 100% at the discretion of the investigator. Primary endpoint was to confirm superior overall survival (OS) of combination therapy vs. monotherapy.
Results:
After 111 of the planned 238 patients were randomized, enrollment was terminated due to poor accrual. In the full-analysis population (group A [n=53] and group B [n=51]), median OS of combination therapy vs. monotherapy was 11.5 vs. 7.5 months (hazard ratio [HR], 0.86; 95% confidence interval [CI], 0.56 to 1.30; p=0.231). Median progression-free survival (PFS) was 5.6 vs. 3.7 months (HR, 0.53; 95% CI, 0.34 to 0.83; p=0.005). In subgroup analyses, patients aged 70-74 years tended to have superior OS with combination therapy (15.9 vs. 7.2 months, p=0.056). Treatment-related adverse events (TRAEs) occurred more frequently in group A vs. group B. However, among severe TRAEs (≥ grade 3), there were no TRAEs with a frequency difference of > 5%.
Conclusion
Combination therapy was associated with numerically improved OS, although statistically insignificant, and a significant PFS benefit compared with monotherapy. Although combination therapy showed more frequent TRAEs, there was no difference in the frequency of severe TRAEs.