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[PMID]:29424495
[Au] Autor:Bekmuhambetov EZ; Mamyrbaev AA; Dzharkenov TA
[Ti] Título:[Hygienic assessment of working conditions in the production of ferro-alloys].
[So] Source:Gig Sanit;95(6):545-8, 2016.
[Is] ISSN:0016-9900
[Cp] País de publicação:Russia (Federation)
[La] Idioma:rus
[Ab] Resumo:This work is devoted to the study of conditions of the work of employees of the modern ferro-alloy production, which was performed in the framework of the evaluation of working places at the Open Joint-Stock Company «Ferrokhrom¼, which is part of Joint-Stock Transnational Company "Kazchrom". The studies were performed with account of the full range of the list of working places, both in the main and auxiliary shops. The work activity of the workers from leading professional groups was established to be conjugate of the impact of the complex of unfavorable factors of occupational environment and labor process. There are given comprehensive measures to improve working conditions and health maintenance in workers from leading professional groups.
[Mh] Termos MeSH primário: Ligas de Cromo
Compostos Ferrosos
Metalurgia
Doenças Profissionais
Saúde Pública/métodos
Local de Trabalho
[Mh] Termos MeSH secundário: Indicadores Básicos de Saúde
Seres Humanos
Cazaquistão/epidemiologia
Metalurgia/métodos
Metalurgia/organização & administração
Metalurgia/normas
Doenças Profissionais/epidemiologia
Doenças Profissionais/etiologia
Doenças Profissionais/prevenção & controle
Exposição Ocupacional/efeitos adversos
Exposição Ocupacional/prevenção & controle
Exposição Ocupacional/estatística & dados numéricos
Saúde da População/estatística & dados numéricos
Medição de Risco
Local de Trabalho/normas
Local de Trabalho/estatística & dados numéricos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chromium Alloys); 0 (Ferrous Compounds)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180301
[Lr] Data última revisão:
180301
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180210
[St] Status:MEDLINE


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[PMID]:29212681
[Au] Autor:Atrey A; Ward SE; Khoshbin A; Hussain N; Bogoch E; Schemitsch EH; Waddell JP
[Ad] Endereço:University of Toronto and St Michael's Hospital, 55 Queen Street E, Level 8, Toronto, Ontario M5C 1R6, Canada.
[Ti] Título:Ten-year follow-up study of three alternative bearing surfaces used in total hip arthroplasty in young patients: a prospective randomised controlled trial.
[So] Source:Bone Joint J;99-B(12):1590-1595, 2017 Dec.
[Is] ISSN:2049-4408
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:AIMS: We present the ten-year data of a cohort of patients, aged between 18 and 65 years (mean age 52.7 years; 19 to 64), who underwent total hip arthroplasty. Patients were randomised to be treated with a cobalt-chrome (CoCr) femoral head with an ultra-high molecular weight polyethylene (UHMWPE), highly cross-linked polyethylene (XLPE) or ceramic-on-ceramic (CoC) bearing surface. PATIENTS AND METHODS: A total of 102 hips (91 patients) were randomised into the three groups. At ten years, 97 hips were available for radiological and functional follow-up. Two hips (two patients) had been revised (one with deep infection and one for periprosthetic fracture) and three were lost to follow-up. Radiological analysis was performed using a validated digital assessment programme to give linear, directional and volumetric wear of the two polyethylene groups. RESULTS: There was a significantly reduced rate of steady-state linear wear with XLPE (0.07 mm/yr) compared with UHMWPE (0.37 mm/yr) (p = 0.001). Volumetric wear was also significantly reduced in the XLPE group (29.29 mm /yr) compared with the UHMWPE group (100.75mm /yr) (p = 0.0001). There were six patients with UHMWPE who had non-progressive osteolysis and none in the XLPE group. All three bearing groups had significant improvements in 12-item short form health survey scores, Western Ontario and McMaster Universities Osteoarthritis Index score and Harris Hip Score. However, the improvement in HSS was significantly less in the UHMWPE group (p = 0.0188) than in the other two groups. At ten years, the rates of volumetric and linear wear in the XLPE group remain low and predominantly below the estimated threshold for osteolysis (1 mm/yr). The rate of linear wear in the XLPE group was three times less than in the UHMWPE group at five-year follow-up and five times less at ten years. The rate of volumetric wear was also three times less in the XLPE group at ten years. CONCLUSION: While CoC also performs well, XLPE at ten years remains a safe and excellent bearing option in young patients, with low rates of wear and no evidence of osteolysis. Cite this article: 2017;99-B:1590-5.
[Mh] Termos MeSH primário: Artroplastia de Quadril/instrumentação
Articulação do Quadril/cirurgia
Prótese de Quadril
Artropatias/cirurgia
Desenho de Prótese
Falha de Prótese
[Mh] Termos MeSH secundário: Adulto
Artroplastia de Quadril/efeitos adversos
Materiais Biocompatíveis
Cerâmica
Ligas de Cromo
Cabeça do Fêmur/cirurgia
Seguimentos
Prótese de Quadril/efeitos adversos
Seres Humanos
Meia-Idade
Polietilenos
Estudos Prospectivos
Adulto Jovem
[Pt] Tipo de publicação:JOURNAL ARTICLE; RANDOMIZED CONTROLLED TRIAL
[Nm] Nome de substância:
0 (Biocompatible Materials); 0 (Chromium Alloys); 0 (Polyethylenes); 0 (ultra-high molecular weight polyethylene)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171213
[Lr] Data última revisão:
171213
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:171208
[St] Status:MEDLINE
[do] DOI:10.1302/0301-620X.99B12.BJJ-2017-0353.R1


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[PMID]:28963151
[Au] Autor:Langton DJ; Sidaginamale RP; Joyce TJ; Meek RD; Bowsher JG; Deehan D; Nargol AVF; Holland JP
[Ad] Endereço:Freeman Hospital, Northern Retrieval Registry, University Hospital of North Tees and Freeman Hospital, Newcastle Upon Tyne, UK.
[Ti] Título:A comparison study of stem taper material loss at similar and mixed metal head-neck taper junctions.
[So] Source:Bone Joint J;99-B(10):1304-1312, 2017 Oct.
[Is] ISSN:2049-4408
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:AIMS: We sought to determine whether cobalt-chromium alloy (CoCr) femoral stem tapers (trunnions) wear more than titanium (Ti) alloy stem tapers (trunnions) when used in a large diameter (LD) metal-on-metal (MoM) hip arthroplasty system. PATIENTS AND METHODS: We performed explant analysis using validated methodology to determine the volumetric material loss at the taper surfaces of explanted LD CoCr MoM hip arthroplasties used with either a Ti alloy (n = 28) or CoCr femoral stem (n = 21). Only 12/14 taper constructs with a rough male taper surface and a nominal included angle close to 5.666° were included. Multiple regression modelling was undertaken using taper angle, taper roughness, bearing diameter (horizontal lever arm) as independent variables. Material loss was mapped using a coordinate measuring machine, profilometry and scanning electron microscopy. RESULTS: After adjustment for other factors, CoCr stem tapers were found to have significantly greater volumetric material loss than the equivalent Ti stem tapers. CONCLUSION: When taper junction damage is identified during revision of a LD MoM hip, it should be suspected that a male taper composed of a standard CoCr alloy has sustained significant changes to the taper cone geometry which are likely to be more extensive than those affecting a Ti alloy stem. Cite this article: 2017;99-B:1304-12.
[Mh] Termos MeSH primário: Artroplastia de Quadril/métodos
Ligas de Cromo
Prótese de Quadril
Próteses Articulares Metal-Metal
[Mh] Termos MeSH secundário: Adulto
Idoso
Idoso de 80 Anos ou mais
Corrosão
Análise de Falha de Equipamento
Feminino
Seres Humanos
Masculino
Microscopia Eletrônica de Varredura
Meia-Idade
Desenho de Prótese
Falha de Prótese
Estresse Mecânico
Propriedades de Superfície
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chromium Alloys)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171012
[Lr] Data última revisão:
171012
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:171001
[St] Status:MEDLINE
[do] DOI:10.1302/0301-620X.99B10.BJJ-2016-1005.R1


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[PMID]:28884275
[Au] Autor:Pourzal R; Hall DJ; Ehrich J; McCarthy SM; Mathew MT; Jacobs JJ; Urban RM
[Ad] Endereço:Department of Orthopedic Surgery, Rush University Medical Center, 1611 W Harrison Street, Suite 204-H, Chicago, IL, 60612, USA. robin_pourzal@rush.edu.
[Ti] Título:Alloy Microstructure Dictates Corrosion Modes in THA Modular Junctions.
[So] Source:Clin Orthop Relat Res;475(12):3026-3043, 2017 Dec.
[Is] ISSN:1528-1132
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Adverse local tissue reactions (ALTRs) triggered by corrosion products from modular taper junctions are a known cause of premature THA failure. CoCrMo devices are of particular concern because cobalt ions and chromium-orthophosphates were shown to be linked to ALTRs, even in metal-on-polyethylene THAs. The most common categories of CoCrMo alloy are cast and wrought alloy, which exhibit fundamental microstructural differences in terms of grain size and hard phases. The impact of implant alloy microstructure on the occurring modes of corrosion and subsequent metal ion release is not well understood. QUESTIONS/PURPOSES: The purpose of this study was to determine whether (1) the microstructure of cast CoCrMo alloy varies broadly between manufacturers and can dictate specific corrosion modes; and whether (2) the microstructure of wrought CoCrMo alloy is more consistent between manufacturers and has low implications on the alloy's corrosion behavior. METHODS: The alloy microstructure of four femoral-stem and three femoral-head designs from four manufacturers was metallographically and electrochemically characterized. Three stem designs were made from cast alloy; all three head designs and one stem design were made from wrought alloy. Alloy samples were sectioned from retrieved components and then polished and etched to visualize grain structure and hard phases such as carbides (eg, M C ) or intermetallic phases (eg, σ phase). Potentiodynamic polarization (PDP) tests were conducted to determine the corrosion potential (E ), corrosion current density (I ), and pitting potential (E ) for each alloy. Four devices were tested within each group, and each measurement was repeated three times to ensure repeatable results. Differences in PDP metrics between manufacturers and between alloys with different hard phase contents were compared using one-way analysis of variance and independent-sample t-tests. Microstructural features such as twin boundaries and slip bands as well as corrosion damage features were viewed and qualitatively assessed in a scanning electron microscope. RESULTS: We found broad variability in implant alloy microstructure for both cast and wrought alloy between manufacturers, but also within the same implant design. In cast alloys, there was no difference in PDP metrics between manufacturers. However, coarse hard phases and clusters of hard phases (mainly intermetallic phases) were associated with severe phase boundary corrosion and pitting corrosion. Furthermore, cast alloys with hard phases had a lower E than those without (0.46 V, SD 0.042; 0.53 V, SD 0.03, respectively; p = 0.015). Wrought alloys exhibited either no hard phases or numerous carbides (M C ). However, the corrosion behavior was mainly affected by lattice defects and banded structures indicative of segregations that appear to be introduced during bar stock manufacturing. Alloys with banding had a lower E (p = 0.008) and higher I (p = 0.028) than alloys without banding (-0.76 V, SD 0.003; -0.73 V, SD 0.009; and 1.14 × 10 mA/cm , SD 1.47 × 10 ; 5.2 × 10 mA/cm , SD 2.57 × 10 , respectively). Alloys with carbides had a slightly higher E (p = 0.046) than those without (-0.755 V, SD 0.005; -0.761 V, SD 0.004); however, alloys with carbides exhibited more severe corrosion damage as a result of phase boundary corrosion, hard phase detachment, and subsequent local crevice corrosion. CONCLUSIONS: The observed variability in CoCrMo alloy microstructure of both cast and wrought components in this study appears to be an important issue to address, perhaps through better standards, to minimize in vivo corrosion. The finding of the banded structures within wrought alloys is especially concerning because it unfavorably influences the corrosion behavior independent of the manufacturer. The findings suggest that a homogeneous alloy microstructure with a minimal hard phase fraction exhibits more favorable corrosion behavior within the in vivo environment of modular taper junctions, thus lowering metal ion release and subsequently the risk of ALTRs to corrosion products. Also, the question arises if hard phases fulfill a useful purpose in metal-on-polyethylene bearings, because they may come with a higher risk of phase boundary corrosion and pitting corrosion and the benefit they provide by adding strength is not needed (unlike in metal-on-metal bearings). CLINICAL RELEVANCE: Implant failure resulting from corrosion processes within modular junctions is a major concern in THA. Our results suggest that implant alloy microstructure is not sufficiently standardized and may also dictate specific corrosion modes and subsequent metal ion release.
[Mh] Termos MeSH primário: Artroplastia de Quadril/instrumentação
Ligas de Cromo/química
Articulação do Quadril/cirurgia
Prótese de Quadril
Polietileno/química
Falha de Prótese
[Mh] Termos MeSH secundário: Artroplastia de Quadril/efeitos adversos
Corrosão
Remoção de Dispositivo
Análise de Falha de Equipamento
Seres Humanos
Desenho de Prótese
Fatores de Risco
Propriedades de Superfície
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chromium Alloys); 9002-88-4 (Polyethylene)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171118
[Lr] Data última revisão:
171118
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:170909
[St] Status:MEDLINE
[do] DOI:10.1007/s11999-017-5486-3


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[PMID]:28869626
[Au] Autor:Rylska D; Sokolowski G; Sokolowski J; Lukomska-Szymanska M
[Ad] Endereço:Institute of Materials Science and Engineering, Technical University of Lódz, Lódz, Poland.
[Ti] Título:Chemical passivation as a method of improving the electrochemical corrosion resistance of Co-Cr-based dental alloy.
[So] Source:Acta Bioeng Biomech;19(2):73-78, 2017.
[Is] ISSN:1509-409X
[Cp] País de publicação:Poland
[La] Idioma:eng
[Ab] Resumo:PURPOSE: The purpose of the study was to evaluate corrosion resistance of Wirobond C® alloy after chemical passivation treatment. METHODS: The alloy surface undergone chemical passivation treatment in four different media. Corrosion studies were carried out by means of electrochemical methods in saline solution. Corrosion effects were determined using SEM. RESULTS: The greatest increase in the alloy polarization resistance was observed for passive layer produced in Na2SO4 solution with graphite. The same layer caused the highest increase in corrosion current. Generally speaking, the alloy passivation in Na2SO4 solution with graphite caused a substantial improvement of the corrosion resistance. The sample after passivation in Na2SO4 solution without graphite, contrary to others, lost its protective properties along with successive anodic polarization cycles. The alloy passivation in Na3PO4 solution with graphite was the only one that caused a decrease in the alloy corrosion properties. The SEM studies of all samples after chemical passivation revealed no pit corrosion - in contrast to the sample without any modification. CONCLUSIONS: Every successive polarization cycle in anodic direction of pure Wirobond C® alloy enhances corrosion resistance shifting corrosion potential in the positive direction and decreasing corrosion current value. The chemical passivation in solutions with low pH values decreases susceptibility to electrochemical corrosion of Co-Cr dental alloy. The best protection against corrosion was obtained after chemical passivation of Wirobond C® in Na2SO4 solution with graphite. Passivation with Na2SO4 in solution of high pH does not cause an increase in corrosion resistance of WIROBOND C. Passivation process increases alloy resistance to pit corrosion.
[Mh] Termos MeSH primário: Ligas de Cromo/síntese química
Materiais Revestidos Biocompatíveis/síntese química
Ligas Dentárias/síntese química
Materiais Dentários/síntese química
Galvanoplastia/métodos
Grafite/química
Sulfatos/química
[Mh] Termos MeSH secundário: Corrosão
Concentração de Íons de Hidrogênio
Teste de Materiais
Cloreto de Sódio/química
Propriedades de Superfície
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chromium Alloys); 0 (Coated Materials, Biocompatible); 0 (Dental Alloys); 0 (Dental Materials); 0 (Sulfates); 0YPR65R21J (sodium sulfate); 451W47IQ8X (Sodium Chloride); 7782-42-5 (Graphite)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171109
[Lr] Data última revisão:
171109
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170905
[St] Status:MEDLINE


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[PMID]:28613055
[Au] Autor:Ye Y; Xiong YY; Zhu JR; Sun J
[Ad] Endereço:Department of Prosthodontics, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine & Shanghai Key Laboratory of Stomatology, Shanghai 200011, China.
[Ti] Título:[Comparison of adaptation and microstructure of titanium upper complete denture base fabricated by selecting laser melting and electron beam melting].
[So] Source:Zhonghua Kou Qiang Yi Xue Za Zhi;52(6):346-350, 2017 Jun 09.
[Is] ISSN:1002-0098
[Cp] País de publicação:China
[La] Idioma:chi
[Ab] Resumo:To fabricate Ti alloy frameworks for a maxillary complete denture with three-dimensional printing (3DP) technique, such as selective laser melting (SLM) and electron beam melting (EBM), and to evaluate the microstructure of these frameworks and their adaptation to the die stone models. Thirty pairs of edentulous casts were divided into 3 groups randomly and equally. In each group, one of the three techniques (SLM, EBM, conventional technique) was used to fabricate Ti alloy frameworks. The base-cast sets were transversally sectioned into 3 sections at the distal of canines, mesial of first molars, and the posterior palatal zone. The gap between the metal base and cast was measured in the 3 sections. Stereoscopic microscope was used to measure the gap. Three pieces of specimens of 5 mm diameter were fabricated with Ti alloy by SLM, EBM and the traditional casting technology (as mentioned above). Scanning electron microscope (SEM) was used to evaluate the differences of microstructure among these specimens. The gaps between the metal base and cast were (99.4±17.0), (98.2±26.1), and (99.6± 16.1) µm in conventional method; (99.4 ± 22.8), (83.1 ± 19.3), and (103.3 ± 13.8) µm in SLM technique; (248.3±70.3), (279.1±71.9), and (189.1±31.6) µm in EBM technique. There was no statistical difference in the value of gaps between SLM Ti alloy and conventional method Ti alloy group ( 0.05). There was statistical difference among EBM Ti alloy, conventional method Ti alloy and SLM Ti alloy group ( 0.05). The SLM Ti alloy showed more uniform and compact microstructure than the cast Ti alloy and EBM Ti alloy did. SLM technique showed initial feasibility to manufacture the dental base of complete denture. The mechanical properties and microstructure of the denture frameworks prepared by SLM indicate that these dentures are appropriate for clinical use. EBM technique is inadequate to make a complete denture now.
[Mh] Termos MeSH primário: Técnica de Fundição Odontológica
Prótese Total
Lasers
Impressão Tridimensional
Titânio
[Mh] Termos MeSH secundário: Ligas de Cromo
Ligas Dentárias
Elétrons
Estudos de Viabilidade
Seres Humanos
Boca Edêntula
Distribuição Aleatória
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chromium Alloys); 0 (Dental Alloys); D1JT611TNE (Titanium)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170906
[Lr] Data última revisão:
170906
[Sb] Subgrupo de revista:D; IM
[Da] Data de entrada para processamento:170615
[St] Status:MEDLINE
[do] DOI:10.3760/cma.j.issn.1002-0098.2017.06.005


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[PMID]:28566399
[Au] Autor:Anderson FL; Koch CN; Elpers ME; Wright TM; Haas SB; Heyse TJ
[Ad] Endereço:Hospital for Special Surgery, 535 East 70th Street, New York, NY 10021, USA.
[Ti] Título:Oxidised zirconium cobalt alloy bearing surfaces in total knee arthroplasty: 3D laser scanning of retrieved polyethylene inserts.
[So] Source:Bone Joint J;99-B(6):793-798, 2017 Jun.
[Is] ISSN:2049-4408
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:AIMS: We sought to establish whether an oxidised zirconium (OxZr) femoral component causes less loss of polyethylene volume than a cobalt alloy (CoCr) femoral component in total knee arthroplasty. MATERIALS AND METHODS: A total of 20 retrieved tibial inserts that had articulated with OxZr components were matched with 20 inserts from CoCr articulations for patient age, body mass index, length of implantation, and revision diagnosis. Changes in dimensions of the articular surfaces were compared with those of pristine inserts using laser scanning. The differences in volume between the retrieved and pristine surfaces of the two groups were calculated and compared. RESULTS: The loss of polyethylene volume was 122 mm (standard deviation (sd) 87) in the OxZr group and 170 mm (sd 96) in the CoCr group (p = 0.033). The volume loss in the OxZr group was also lower in the medial (72 mm (sd 67) 92 mm (sd 60); p = 0.096) and lateral (49 mm (sd 36) 79 mm (sd 61); p = 0.096) compartments separately, but these differences were not significant. CONCLUSION: Our results corroborate earlier findings from testing and visual retrieval analysis which suggest that polyethylene volume loss is lower with OxZr femoral components. Since both OxZr and CoCr are hard surfaces that would be expected to create comparable amounts of polyethylene creep, the differences in volume loss may reflect differences in the wear of these inserts. Cite this article: 2017;99-B:793-8.
[Mh] Termos MeSH primário: Artroplastia do Joelho/instrumentação
Cobalto
Prótese do Joelho
Zircônio
[Mh] Termos MeSH secundário: Adulto
Idoso
Idoso de 80 Anos ou mais
Artroplastia do Joelho/métodos
Ligas de Cromo
Feminino
Seres Humanos
Imagem Tridimensional/métodos
Lasers
Masculino
Teste de Materiais/métodos
Meia-Idade
Polietileno
Desenho de Prótese
Falha de Prótese
Reoperação
Propriedades de Superfície
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chromium Alloys); 3G0H8C9362 (Cobalt); 9002-88-4 (Polyethylene); C6V6S92N3C (Zirconium); S38N85C5G0 (zirconium oxide)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170821
[Lr] Data última revisão:
170821
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:170602
[St] Status:MEDLINE
[do] DOI:10.1302/0301-620X.99B6.BJJ-2016-1281.R1


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[PMID]:28427980
[Au] Autor:Han S; Hyun SJ; Kim KJ; Jahng TA; Kim HJ
[Ad] Endereço:Department of Neurosurgery, Spine Center, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, South Korea.
[Ti] Título:Comparative Study Between Cobalt Chrome and Titanium Alloy Rods for Multilevel Spinal Fusion: Proximal Junctional Kyphosis More Frequently Occurred in Patients Having Cobalt Chrome Rods.
[So] Source:World Neurosurg;103:404-409, 2017 Jul.
[Is] ISSN:1878-8769
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: The use of titanium alloy (Ti) rods is frequently associated with rod fracture after spinal fixation. To address this issue, cobalt chrome (CoCr) rods, which are advantageous because of their greater strength and resistance to fatigue relative to Ti rods, have been introduced. The purpose of the present study was to compare radiographic outcomes after the use of Ti versus CoCr rods in a matched cohort of patients undergoing posterior spinal fusion for treatment of spinal instability. METHODS: We retrospectively reviewed data from patients who had undergone spinal fusion involving more than 3 levels at a single institution between 2004 and 2015. Patients were matched for age, diagnosis, 3-column osteotomy, levels fused, and T score. Fifty patients with Ti rods were identified and appropriately matched to 50 consecutive patients with CoCr rods. RESULTS: The distributions of age at surgery, sex, diagnosis, 3-column osteotomy, levels fused, number of patients with previous surgical procedures, and T score did not significantly differ between the 2 groups. However, there were significant differences in length of follow-up (CoCr, 25.0 vs. Ti, 28.5 months; P < 0.001), fusion rate (CoCr, 45 [90%] vs. Ti, 33 [66%]; P = 0.004), occurrence of rod breakage (CoCr, 0 vs. T, 8 [16%]; P = 0.006), and junctional kyphosis (CoCr, 24 [46%] vs. Ti, 9 [18%]; P = 0.003). CONCLUSIONS: Our findings indicate that the use of CoCr rods is effective in ensuring stability of the posterior spinal construct and accomplishment of spinal fusion. Furthermore, our results indicate that junctional kyphosis may occur more frequently in CoCr systems than in Ti systems.
[Mh] Termos MeSH primário: Ligas de Cromo/uso terapêutico
Cobalto/uso terapêutico
Cifose/etiologia
Fusão Vertebral/instrumentação
Titânio/uso terapêutico
[Mh] Termos MeSH secundário: Adulto
Idoso
Idoso de 80 Anos ou mais
Feminino
Seres Humanos
Fixadores Internos
Instabilidade Articular/diagnóstico por imagem
Instabilidade Articular/cirurgia
Cifose/diagnóstico por imagem
Masculino
Meia-Idade
Complicações Pós-Operatórias/etiologia
Estudos Retrospectivos
Doenças da Coluna Vertebral/diagnóstico por imagem
Doenças da Coluna Vertebral/cirurgia
Resultado do Tratamento
Adulto Jovem
[Pt] Tipo de publicação:COMPARATIVE STUDY; EVALUATION STUDIES; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chromium Alloys); 3G0H8C9362 (Cobalt); D1JT611TNE (Titanium)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170925
[Lr] Data última revisão:
170925
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170422
[St] Status:MEDLINE


  9 / 3777 MEDLINE  
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[PMID]:28350880
[Au] Autor:Lu C; Zheng Y; Zhong Q
[Ad] Endereço:Yongjia Clinic, Shanghai Stomatological Hospital, Fudan University, Shanghai, People's Republic of China.
[Ti] Título:Corrosion of dental alloys in artificial saliva with Streptococcus mutans.
[So] Source:PLoS One;12(3):e0174440, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:A comparative study of the corrosion resistance of CoCr and NiCr alloys in artificial saliva (AS) containing tryptic soy broth (Solution 1) and Streptococcus mutans (S. mutans) species (Solution 2) was performed by electrochemical methods, including open circuit potential measurements, impedance spectroscopy, and potentiodynamic polarization. The adherence of S. mutans to the NiCr and CoCr alloy surfaces immersed in Solution 2 for 24 h was verified by scanning electron microscopy, while the results of electrochemical impedance spectroscopy confirmed the importance of biofilm formation for the corrosion process. The R(QR) equivalent circuit was successfully used to fit the data obtained for the AS mixture without S. mutans, while the R(Q(R(QR))) circuit was found to be more suitable for describing the biofilm properties after treatment with the AS containing S. mutans species. In addition, a negative shift of the open circuit potential with immersion time was observed for all samples regardless of the solution type. Both alloys exhibited higher charge transfer resistance after treatment with Solution 2, and lower corrosion current densities were detected for all samples in the presence of S. mutans. The obtained results suggest that the biofilm formation observed after 24 h of exposure to S. mutans bacteria might enhance the corrosion resistance of the studied samples by creating physical barriers that prevented oxygen interactions with the metal surfaces.
[Mh] Termos MeSH primário: Corrosão
Ligas Dentárias/química
Saliva Artificial/farmacologia
Streptococcus mutans/efeitos dos fármacos
[Mh] Termos MeSH secundário: Aderência Bacteriana/efeitos dos fármacos
Biofilmes/efeitos dos fármacos
Biofilmes/crescimento & desenvolvimento
Ligas de Cromo/química
Ligas de Cromo/normas
Cobalto/química
Ligas Dentárias/normas
Espectroscopia Dielétrica
Técnicas Eletroquímicas
Seres Humanos
Concentração de Íons de Hidrogênio
Teste de Materiais/métodos
Microscopia Eletrônica de Varredura
Níquel/química
Saliva Artificial/química
Streptococcus mutans/fisiologia
Streptococcus mutans/ultraestrutura
Propriedades de Superfície
Fatores de Tempo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chromium Alloys); 0 (Dental Alloys); 0 (Saliva, Artificial); 3G0H8C9362 (Cobalt); 7OV03QG267 (Nickel)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170831
[Lr] Data última revisão:
170831
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170329
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0174440


  10 / 3777 MEDLINE  
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[PMID]:28326734
[Au] Autor:Xinyu L; Xiangfeng M
[Ad] Endereço:Dept. of Prosthodontics, Nanjing Stomatological Hospital, The Affiliated Stomatological Hospital, Medical School of Nanjing University, Nanjing 210008, China;Wuxi Yaboshi Dental Clinic, Wuxi 214000, China.
[Ti] Título:[Research on bond durability among different core materials and zirconia ceramic cemented by self-adhesive resin cements].
[So] Source:Hua Xi Kou Qiang Yi Xue Za Zhi;35(1):89-92, 2017 Feb 01.
[Is] ISSN:1000-1182
[Cp] País de publicação:China
[La] Idioma:chi
[Ab] Resumo:OBJECTIVE: This research estimated shear bond durability of zirconia and different substrates cemented by two self-adhesive resin cements (Clearfil SA Luting and RelyX U100) before and after aging conditioning. METHODS: Machined zirconia ceramic discs were cemented with four kinds of core material (cobalt-chromium alloy, flowable composite resin core material, packable composite resin, and dentin) with two self-adhesive resin cements (Clearfil SA Luting and RelyX U100). All specimens were divided into eight test groups, and each test group was divided into two subgroups. Each subgroup was subjected to shear test before and after 10 000 thermal cycles. RESULTS: All factors (core materials, cements, and thermal cycle) significantly influenced bond durability of zirconia ceramic (P<0.00 1). After 10 000 thermal cycles, significant decrease was not observed in shear bond strength of cobalt-chromium alloy luted with Clearfil SA Luting (P>0.05); observed shear bond strength was significantly higher than those of other substrates (P<0.05). Significantly higher shear bond strength was noted in Clearfil SA Luting luted with cobalt-chromium alloy, flowable composite resin core material, and packable composite resin than that of RelyX U100 (P<0.05). However, significant difference was not observed in shear bond strength of dentin luted with Clearfil SA Luting and RelyX U100 (P>0.05). CONCLUSIONS: Different core materials and self-adhesive resin cements can significantly affect bond durability of zirconia ceramic. 
.
[Mh] Termos MeSH primário: Colagem Dentária
[Mh] Termos MeSH secundário: Adesivos
Cerâmica
Ligas de Cromo
Resinas Compostas
Cemento Dentário
Dentina
Seres Humanos
Teste de Materiais
Cimentos de Resina
Zircônio
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Adhesives); 0 (Chromium Alloys); 0 (Clearfil SA); 0 (Composite Resins); 0 (Resin Cements); 0 (flowable hybrid composite); C6V6S92N3C (Zirconium)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170412
[Lr] Data última revisão:
170412
[Sb] Subgrupo de revista:D; IM
[Da] Data de entrada para processamento:170323
[St] Status:MEDLINE
[do] DOI:10.7518/hxkq.2017.01.014



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