24 research outputs found

    Role of coefficient of thermal expansion on bond strength of ceramic veneered yttrium-stabilized zirconia

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    Incompatible coefficient of thermal expansion (CTE) is supposed to be a reason for chipping of ceramic veneered zirconia. This study evaluates the effect of veneering ceramic at varied CTE on bond strength to zirconia. Zirconia disks (Z, Ø 10 mm, 1.0 mm thickness) were prepared from Y-TZP (Cercon®) and sintered at 1350°C for 6 hours. All zirconia disks were veneered with ceramics ((Ø 7.0 mm, 1.5 mm thickness) with varied CTE including VITADur® alpha (VD?), VITAVM®7 (VM7), VITAVM®9 (VM9), Cercon® ceramkiss (CCK), IPSe.max® ceram (IeC), and IPS dSIGN® (IdS) (n=15). The specimens were thermo-cycled (5-55 °C, 500 cycles) prior to determine the shear bond strength on a universal testing machine. The veneering ceramic and zirconia rods (Ø 4 mm, 30 mm length) were prepared for CTE evaluation. ANOVA and Tukey?s multiple comparisons were used to determine the statistically significant difference (?=0.05). Weibull analysis was applied for survival probability, Weibull modulus (m), and characteristics strength (?o) of the shear bond. The interfaces were microscopically examined. The phase transformation of zirconia was determined using X ray diffraction. The mean±sd (MPa), m, and ?o of bond strength were 20.45±2.32, 9.25, and 21.53 for Z-VD?, 19.47±4.53, 4.66, and 20.31 for Z-VM7, 21.05±3.96, 5.61, and 21.88 for Z-IeC, 25.85±2.74, 9.93, and 27.15 for Z-VM9, 25.82±4.39, 6.27, and 27.06 for Z-CCK, and 2.96±0.73, 4.11, and 3.28 for Z-IdS. The CTE (×10-6/°C) were 10.80, 7.83, 7.87, 9.86, 9.93, 10.03, and 12.95 for Z, VD?, VM7, IeC, VM9, CCK, and IdS. The bond strength was significantly affected by the CTE difference (p<0.05). The t?m phase transformation related with the CTE difference. The CTE?s differences induced stress that affected the bond strength. CTE?s compatibility of veneering ceramic to zirconia is crucial for enhancing the bond strength. The CTE difference approximately 0.77-0.87×10-6/°C was recommended

    A European patient record study on diagnosis and treatment of chemotherapy-induced anaemia

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    Purpose – Patients with cancer frequently experience chemotherapy‐induced anaemia (CIA) and iron deficiency (ID). Erythropoiesis‐stimulating agents (ESA), iron supplementation and blood transfusions are available therapies. This study evaluated routine practice in CIA management. Methods – Medical oncologists and/or haematologists from nine European countries (n=375) were surveyed on their last five cancer patients treated for CIA (n=1730). Information was collected on tests performed at diagnosis of anaemia, levels of haemoglobin (Hb), serum ferritin and transferrin saturation (TSAT), and applied anaemia therapies. Results – Diagnostic tests and therapies for CIA varied across Europe. Anaemia and iron status were mainly assessed by Hb (94%) and ferritin (48%) measurements. TSAT was only tested in 14%. At anaemia diagnosis, 74% of patients had Hb ≤10g/dL, including 15% with severe (Hb <8g/dL) anaemia. Low iron levels (ferritin ≤100ng/mL) were detected in 42% of evaluated patients. ESA was the most commonly used treatment (63%) and 30% of ESA‐treated patients also received iron supplementation. Most iron‐treated patients (74%) received an oral iron; intravenous iron was administered to 26%. 52% of patients received transfusions and in 76% of these, transfusions formed part of a regular anaemia treatment regimen. Management practices were similar in 2009 and 2011. Conclusion – Management of anaemia and iron status in patients treated for CIA varies substantially across Europe. Iron status is only assessed in half of the patients. In contrast to clinical evidence, iron treatment is underutilised and mainly based on oral iron supplementation. Implementation of guidelines needs to be increased, particularly the minimisation of blood transfusions

    Potential health economic impact of intravenous iron supplementation to erythropoiesis-stimulating agent treatment in patients with cancer- or chemotherapy-induced anemia

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    Background: Intravenous (i.v.) iron supplementation significantly improves the response to erythropoiesis-stimulating agent (ESA)-based therapies in patients with cancer- or chemotherapy-induced anemia. The economic implications of adding i.v. iron to ESA treatment are less well investigated. Published randomized controlled trials do not provide sufficient data for a comprehensive cost-effectiveness analysis. Methods: Preliminary cost calculations from the Swiss health care system perspective based on a meta-analysis and published results of eight randomized controlled trials without correction for decreased ESA need provide a conservative cost-effectiveness estimate. Results: The additional total cost of i.v. iron supplementation ranged from EUR 417 to EUR 901 per patient depending on the evaluated iron-carbohydrate complex. Considering a 24% absolute increase in the proportion of ESA responders, the incremental cost-effectiveness ratios per additional responder are EUR 1,704-3,686. In routine practice, better values may be achieved due to ESA dose savings. Conclusion: Supplementation of ESAs with i.v. iron appears to be an economically viable treatment option in anemic cancer patients. Additional research on ESA dose savings and cost-effectiveness is required
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