1.Interfacial modulus mapping of layered dental ceramics using nanoindentation.
Antonios L THEOCHAROPOULOS ; Andrew J BUSHBY ; Ken MY P'NG ; Rory M WILSON ; K Elizabeth TANNER ; Michael J CATTELL
The Journal of Advanced Prosthodontics 2016;8(6):479-488
PURPOSE: The aim of this study was to test the modulus of elasticity (E) across the interfaces of yttria stabilized zirconia (YTZP) / veneer multilayers using nanoindentation. MATERIALS AND METHODS: YTZP core material (KaVo-Everest, Germany) specimens were either coated with a liner (IPS e.max ZirLiner, Ivoclar-Vivadent) (Type-1) or left as-sintered (Type-2) and subsequently veneered with a pressable glass-ceramic (IPS e.max ZirPress, Ivoclar-Vivadent). A 5 µm (nominal tip diameter) spherical indenter was used with a UMIS CSIRO 2000 (ASI, Canberra, Australia) nanoindenter system to test E across the exposed and polished interfaces of both specimen types. The multiple point load – partial unload method was used for E determination. All materials used were characterized using Scanning Electron Microscopy (SEM) and X – ray powder diffraction (XRD). E mappings of the areas tested were produced from the nanoindentation data. RESULTS: A significantly (P<.05) lower E value between Type-1 and Type-2 specimens at a distance of 40 µm in the veneer material was associated with the liner. XRD and SEM characterization of the zirconia sample showed a fine grained bulk tetragonal phase. IPS e-max ZirPress and IPS e-max ZirLiner materials were characterized as amorphous. CONCLUSION: The liner between the YTZP core and the heat pressed veneer may act as a weak link in this dental multilayer due to its significantly (P<.05) lower E. The present study has shown nanoindentation using spherical indentation and the multiple point load - partial unload method to be reliable predictors of E and useful evaluation tools for layered dental ceramic interfaces.
Ceramics*
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Elastic Modulus
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Hot Temperature
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Methods
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Microscopy, Electron, Scanning
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Powder Diffraction
2.Prevention of contrast-induced nephropathy by Cordyceps among patients undergoing percutaneous coronary procedures using intravenous contrast.
Marvyn Allen G. CHAN ; Kenneth Wilson O. LIM ; Elizabeth SALAZAR-MONTEMAYOR
Acta Medica Philippina 2018;52(1):4-16
OBJECTIVES: This study aimed to determine the efficacy and safety of Cordyceps in preventing occurrence of contrast-induced nephropathy (CIN) among patients undergoing CA / PCI using IV contrast compared to standard therapy.
METHODS: We searched Medline, Embase, Cochrane database, and Google Scholars for RCTs involving the use of Cordyceps in contrast-induced nephropathy. We used the search keywords "Cordyceps" and "contrast-induced nephropathy" with the Boolean operator "AND" and filtering search results to include only randomized controlled trials and clinical trials. Three trials were found which satisfied all the inclusion criteria and none of the exclusion criteria.
RESULTS: No patient developed clinical renal failure, adverse reactions, or side effects with the Cordyceps arm. CIN occurred in 26 out of 285 patients. The incidence of CIN was less in the Cordyceps group compared to the standard therapy group (p < 0.05, CI 0.20, 1.00).
CONCLUSION: Cordyceps shows a trend towards prevention of CIN and a decrease in biomarkers for acute kidney injury. More studies with larger populations need to be performed to further clarify its preventive effects.
Human ; Acute Kidney Injury ; Cordyceps ; Meta-analysis
3.Multicentre collaborative cohort study of the use of Kirschner wires for the management of supracondylar fractures in children.
Henry CLAIREAUX ; Richard GOODALL ; Joshua HILL ; Elizabeth WILSON ; Philippa COULL ; Sebastian GREEN ; James SCHUSTER-BRUCE ; Diana LIM ; Joanna MILES ; Payam TARASSOLI
Chinese Journal of Traumatology 2019;22(5):249-254
PURPOSE:
Supracondylar fractures of the humerus cause significant morbidity in children. Nerve damage and loss of fracture reduction are common recognised complications in patients with this injury. Uncertainty surrounds the optimal Kirschner wire configuration and diameter for closed reduction and pinning of these fractures. This study describes current practice and examined the association between wire configuration or diameter and outcomes (clinical and radiological) in the operative management of paediatric supracondylar fractures.
METHODS:
Children presenting with Gartland II or III supracondylar fractures at five hospitals in south-west England were eligible for inclusion. Collaborators scrutinised paper and electronic case notes. Outcome measures were maintenance of reduction and iatrogenic nerve injury.
RESULTS:
Altogether 209 patients were eligible for inclusion: 15.7% had a documented neurological deficit at presentation; 3.9% who were neurologically intact at presentation sustained a new deficit caused by treatment and 13.4% experienced a clinically significant loss of reduction following fixation. Maintenance of reduction was significantly better in patients treated specifically with crossed ×3 Kirschner wire configuration compared to all other configurations. The incidence of iatrogenic nerve injury was not significantly different between groups treated with different wire configurations.
CONCLUSION
We present a large multicentre cohort study showing that crossed ×3 Kirschner wires are associated with better maintenance of reduction than crossed ×2 or lateral entry wires. Greater numbers would be required to properly investigate nerve injury relating to operative management of supracondylar fractures. We found significant variations in practice and compliance with the British Orthopaedic Association Standard for Trauma (BOAST) 11 guidelines.