2,948 research outputs found
Immediate implant-retained prosthetic obturation after maxillectomy based on zygomatic implant placement by 3D-guided surgery:a cadaver study
Abstract Background The aim of this study was to introduce a complete 3D workflow for immediate implant retained prosthetic rehabilitation following maxillectomy in cancer surgery. The workflow consists of a 3D virtual surgical planning for tumor resection, zygomatic implant placement, and for an implant-retained prosthetic-obturator to fit the planned outcome situation for immediate loading. Materials and methods In this study, 3D virtual surgical planning and resection of the maxilla, followed by guided placement of 10 zygomatic implants, using custom cutting and drill/placement-guides, was performed on 5 fresh frozen human cadavers. A preoperatively digitally designed and printed obturator prosthesis was placed and connected to the zygomatic implants. The accuracy of the implant positioning was obtained using 3D deviation analysis by merging the pre- and post-operative CT scan datasets. Results The preoperatively designed and manufactured obturator prostheses matched accurately the per-operative implant positions. All five obturators could be placed and fixated for immediate loading. The mean prosthetic point deviation on the cadavers was 1.03 ± 0.85 mm; the mean entry point deviation was 1.20 ± 0.62 mm; and the 3D angle deviation was 2.97 ± 1.44°. Conclusions It is possible to 3D plan and accurately execute the ablative surgery, placement of zygomatic implants, and immediate placement of an implant-retained obturator prosthesis with 3D virtual surgical planning.The next step is to apply the workflow in the operating room in patients planned for maxillectomy
Guided placement of zygomatic implants in head and neck cancer patients:implant survival and patient outcomes at 1-3 years of follow-up
Zygomatic implants (ZI) are a valuable option for supporting an obturator prosthesis after maxillary resection. This study was performed to assess the clinical outcomes of a digitally validated guided technique for ZI placement, followed by immediate prosthetic obturation. The primary objective was to evaluate implant survival, while the secondary objective was to assess patient-reported quality of life post-rehabilitation. Twelve patients treated for head and neck cancer received a total of 36 ZI after ablative surgery. The mean duration of ZI follow-up was 30.1 months. The survival rate of ZI placed in non-irradiated patients was 100%, while it was 85% in irradiated patients. Patient-reported outcomes were evaluated using the Liverpool Oral Rehabilitation Questionnaire (LORQv3) and the University of Washington Quality of Life Questionnaire (UW-QOL v4). Most patients reported satisfactory outcomes in the oral function domain of the LORQv3 (mean score 17.7 ± 4.5; possible range 12-48, with lower scores indicating better outcomes). Regarding the UW-QOL v4, the swallowing and chewing domains had the highest scores (mean 97.5 ± 8.7 and 95.8 ± 14.4, respectively; maximum possible score of 100). In conclusion, this treatment approach improves function and quality of life after maxillary ablative surgery. However, irradiated patients showed a noticeable trend of higher implant failure, and this was influenced by tumour position and size impacting the radiation dose to the zygomatic bone.</p
Local host response following an intramammary challenge with Staphylococcus fleurettii and different strains of Staphylococcus chromogenes in dairy heifers
Coagulase-negative staphylococci (CNS) are a common cause of subclinical mastitis in dairy cattle. The CNS inhabit various ecological habitats, ranging between the environment and the host. In order to obtain a better insight into the host response, an experimental infection was carried out in eight healthy heifers in mid-lactation with three different CNS strains: a Staphylococcus fleurettii strain originating from sawdust bedding, an intramammary Staphylococcus chromogenes strain originating from a persistent intramammary infection (S. chromogenes IM) and a S. chromogenes strain isolated from a heifer's teat apex (S. chromogenes TA). Each heifer was inoculated in the mammary gland with 1.0 x 10(6) colony forming units of each bacterial strain (one strain per udder quarter), whereas the remaining quarter was infused with phosphate-buffered saline. Overall, the CNS evoked a mild local host response. The somatic cell count increased in all S. fleurettii-inoculated quarters, although the strain was eliminated within 12 h. The two S. chromogenes strains were shed in larger numbers for a longer period. Bacterial and somatic cell counts, as well as neutrophil responses, were higher after inoculation with S. chromogenes IM than with S. chromogenes TA. In conclusion, these results suggest that S. chromogenes might be better adapted to the mammary gland than S. fleurettii. Furthermore, not all S. chromogenes strains induce the same local host response
Search for supersymmetry in pp collisions at 7 TeV in events with jets and missing transverse energy
A search for supersymmetry with R-parity conservation in proton-proton collisions at a centre-of-mass energy of 7 TeV is presented. The data correspond to an integrated luminosity of 35 inverse picobarns collected by the CMS experiment at the LHC. The search is performed in events with jets and significant missing transverse energy, characteristic of the decays of heavy, pair-produced squarks and gluinos. The primary background, from standard model multijet production, is reduced by several orders of magnitude to a negligible level by the application of a set of robust kinematic requirements. With this selection, the data are consistent with the standard model backgrounds, namely t t-bar, W + jet and Z + jet production, which are estimated from data control samples. Limits are set on the parameters of the constrained minimal supersymmetric extension of the standard model. These limits extend those set previously by experiments at the Tevatron and LEP colliders
Use of dementia care mapping in the care for older people with intellectual disabilities: A mixedâmethod study
Background The ageing of people with intellectual disabilities, with associated morbidity like dementia, calls for new types of care. Personâcentred methods may support care staff in providing this, an example being Dementia Care Mapping (DCM). DCM has been shown to be feasible in IDâcare. We examined the experiences of IDâprofessionals in using DCM. Methods We performed a mixedâmethods study, using quantitative data from care staff (N = 136) and qualitative data (focusâgroups, individual interviews) from care staff, group home managers and DCMâinâintellectual disabilities mappers (N = 53). Results DCM provided new insights into the behaviours of clients, enabled professional reflection and gave new knowledge and skills regarding dementia and personâcentred care. Appreciation of DCM further increased after the second cycle of application. Conclusion DCM is perceived as valuable in IDâcare. Further assessment is needed of its effectiveness in IDâcare with respect to quality of care, staffâclient interactions and job performance
Proximity effect, quasiparticle transport, and local magnetic moment in ferromagnet-d-wave superconductor junctions
The proximity effect, quasiparticle transport, and local magnetic moment in
ferromagnet--d-wave superconductor junctions with {110}-oriented interface are
studied by solving self-consistently the Bogoliubov-de Gennes equations within
an extended Hubbard model. It is found that the proximity induced order
parameter oscillates in the ferromagnetic region. The modulation period is
shortened with the increased exchange field while the oscillation amplitude is
depressed by the interfacial scattering. With the determined superconducting
energy gap, a transfer matrix method is proposed to compute the subgap
conductance within a scattering approach. Many novel features including the
zero-bias conductance dip and splitting are exhibited with appropriate values
of the exchange field and interfacial scattering strength. The conductance
spectrum can be influenced seriously by the spin-flip interfacial scattering.
In addition, a sizable local magnetic moment near the {110}-oriented surface of
the d-wave superconductor is discussed.Comment: 10 pages, 16 ps-figures, to appear in Phys. Rev.
Phase separation and enhanced charge-spin coupling near magnetic transitions
The generic changes of the electronic compressibility in systems which show
magnetic instabilities is studied. It is shown that, when going into the
ordered phase, the compressibility is reduced by an amount comparable to the
its original value, making charge instabilities also possible. We discuss,
within this framework, the tendency towards phase separation of the double
exchange systems, the pyrochlores, and other magnetic materials
Measurement of the tÂŻt production cross section in pp collisions at âs = 7 TeV using the kinematic properties of events with leptons and jets
A measurement of the tt production cross section in proton-proton collisions at a centre-of-mass energy of 7 TeV has been performed at the LHC with the CMS detector. The analysis uses a data sample corresponding to an integrated luminosity of 36 pbâ1 and is based on the reconstruction of the final state with one isolated, high transverse-momentum electron or muon and three or more hadronic jets. The kinematic properties of the events are used to separate the tt signal from W+jets and QCD multijet background events. The measured cross section is 173+39â32 (stat+syst) pb, consistent with standard model expectations
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