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1.
Radiol Case Rep ; 19(11): 5248-5252, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39280741

RESUMO

Thrombus migration is a well-known clinical condition that occurs before mechanical thrombectomy and after intravenous thrombolysis in patients with anterior circulation strokes. Although thrombus migration from the vertebral artery (VA) can result in life-threatening basilar artery (BA) occlusion, its occurrence in the posterior circulation has rarely been discussed. Two patients with secondary BA occlusion caused by spontaneous thrombus migration from the VA are presented. A 60-year-old man with a left cerebellar infarction secondary to ipsilateral VA occlusion was admitted to our hospital 8 hours after onset, with a National Institute of Health Stroke Scale (NIHSS) score of 4. The patient became comatose 3.5 hours after arrival owing to subsequent BA occlusion. He was successfully treated with mechanical thrombectomy. A 74-year-old man with right cerebellar infarction secondary to ipsilateral VA occlusion was admitted to our hospital 26 hours after onset, with an NIHSS score of 3. He became comatose 1 hour after arrival owing to BA occlusion and was treated with thrombectomy, followed by internal and external decompression. Despite the mild symptoms of VA occlusion and consequently delayed admission to the hospital, stroke physicians should be aware that spontaneous thrombus migration from the VA to the BA can result in a life-threatening presentation.

2.
Nanoscale Adv ; 5(7): 1990-1998, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36998652

RESUMO

Transparent tungsten trioxide thin films, which demonstrated visible-light (Vis-light)-induced superhydrophilicity, with thicknesses of 100-120 nm, adhesion strengths greater than 49 MPa, bandgap energies of 2.8-2.9 eV, and haze values of 0.4-0.5%, were fabricated using a solution-based process on quartz glass substrates. The precursor solution was prepared by dissolving a W6+ complex salt isolated from a reacted solution of tungstic acid, citric acid, and dibutylamine in H2O, in ethanol. By heating the spin-coated films in air for 30 min at temperatures higher than 500 °C, crystallized WO3 thin films were obtained. The O/W atomic ratio was evaluated to be 2.90, based on the peak area analysis of X-ray photoelectron spectroscopy spectra of the thin-film surfaces, indicating the co-presence of W5+ ions. The water contact angle on film surfaces, which was approximately 25° prior to light irradiation, decreased to less than 10° upon irradiation with 0.06 mW cm-2 Vis-light for only 20 min at 20-25 °C and a relative humidity (RH) of 40-50%. By comparing the contact angle changes at RH values of 20-25%, it was revealed that the interaction between ambient water molecules and the partially O-deficient WO3 thin films plays an important role in achieving photoinduced superhydrophilicity.

3.
Intern Med ; 61(16): 2483-2487, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35110491

RESUMO

Spontaneous dissection of the brachiocephalic artery is rare, and there is insufficient evidence for optimal treatment. We herein report a case of ischemic stroke due to spontaneous dissection of the brachiocephalic to the right common carotid artery. The patient was treated medically but died suddenly 18 days after the onset because of aortic dissection. Although almost all reported cases of spontaneous dissection of the brachiocephalic artery have had good outcomes with medical management, it is important to note that sudden development of aortic dissection might occur, even without initial findings suggestive of this condition.


Assuntos
Dissecção Aórtica , AVC Isquêmico , Dissecção Aórtica/complicações , Dissecção Aórtica/diagnóstico por imagem , Aorta , Tronco Braquiocefálico/diagnóstico por imagem , Artéria Carótida Primitiva/diagnóstico por imagem , Humanos
4.
J Neuroendovasc Ther ; 16(6): 327-334, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37501893

RESUMO

Objective: There are few reports on endovascular treatment of tandem lesions in the posterior circulation and no consensus on treatment strategies has been reached. We report a case of tandem lesions of basilar artery occlusion and vertebral artery stenosis treated by thrombectomy and vertebral artery stenting. Case Presentation: We present the case of a 73-year-old man who developed consciousness disorder and tetraplegia. Head and neck CTA revealed tandem left vertebral artery stenosis and basilar artery occlusion. The patient was treated using a reverse technique, which involves performing thrombectomy first and then vertebral artery stenting, along with Carotid Guardwire PS. Postoperative impairment of consciousness and improvement of tetraplegia were achieved. Conclusion: The reverse technique combined with Carotid Guardwire PS may be a useful treatment strategy for tandem lesions in the posterior circulation.

5.
Oxf Med Case Reports ; 2021(11): omab118, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34909206
6.
Nanomaterials (Basel) ; 11(12)2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34947702

RESUMO

A single-walled carbon nanotube/anatase (SWCNT/anatase) composite thin film with a transmittance of over 70% in the visible-light region was fabricated on a quartz glass substrate by heat treating a precursor film at 500 °C in air. The precursor film was formed by spin coating a mixed solution of the titania molecular precursor and well-dispersed SWCNTs (0.075 mass%) in ethanol. The anatase crystals and Ti3+ ions in the composite thin films were determined by X-ray diffraction and X-ray photoelectron spectroscopy, respectively. The effect of the heating process on the SWCNTs was analyzed using Raman spectroscopy. The composite film showed an even surface with a scratch resistance of 4H pencil hardness, as observed using field-emission scanning electron microscopy and atomic force microscopy. The electrical resistivity and optical bandgap energy of the composite thin film with a thickness of 100 nm were 6.6 × 10-2 Ω cm and 3.4 eV, respectively, when the SWCNT content in the composite thin film was 2.9 mass%. An anodic photocurrent density of 4.2 µA cm-2 was observed under ultraviolet light irradiation (16 mW cm-2 at 365 nm) onto the composite thin film, thus showing excellent properties as a photoelectrode without conductive substrates.

7.
Nanomaterials (Basel) ; 11(12)2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34947753

RESUMO

A single-walled carbon nanotube (SWCNT)-silica composite thin film on a quartz glass was formed by ultraviolet irradiation (20-40 °C) onto a spin-coated precursor film. With 7.4 mass% SWCNTs, the electrical resistivity reached 7.7 × 10-3 Ω·cm after UV-irradiation. The transmittance was >80% at 178-2600 nm, and 79%-73% at 220-352 nm. Heat treatment increased the transparency and pencil hardness, without affecting the low electrical resistivity. Raman spectroscopy and microscopic analyses revealed the excellent film morphology with good SWCNT dispersal. The low refractive index (1.49) and haze value (<1.5%) are invaluable for transparent windows for novel optoelectronic devices.

8.
Nanomaterials (Basel) ; 11(5)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065343

RESUMO

Deep-ultraviolet (DUV) light-transparent conductive composite thin films, consisting of dispersed multiwalled carbon nanotubes (MWCNTs) and SiO2 matrix composites, were fabricated on a quartz glass substrate. Transparent and well-adhered amorphous thin films, with a thickness of 220 nm, were obtained by weak ultraviolet (UV) irradiation (4 mW cm-2 at 254 nm) for more than 6 h at 20-40 °C onto the precursor films, which were obtained by spin coating with a mixed solution of MWCNT in water and Si(IV) complex in ethanol. The electrical resistivity of MWCNT/SiO2 composite thin film is 0.7 Ω·cm, and transmittance in the wavelength region from DUV to visible light is higher than 80%. The MWCNT/SiO2 composite thin film showed scratch resistance at pencil hardness of 8H. Importantly, the resistivity of the MWCNT/SiO2 composite thin film was maintained at the original level even after heat treatment at 500 °C for 1 h. It was observed that the heat treatment of the composite thin film improved durability against both aqueous solutions involving a strong acid (HCl) and a strong base (NaOH).

9.
Nihon Ronen Igakkai Zasshi ; 57(2): 182-194, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32475946

RESUMO

AIM: To verify the clinical utility of instrumental activities of daily life evaluated using the Tokyo Metropolitan Institute of Gerontology index of competence (TMIG-IC) as a screening tool for patients with early-phase cognitive impairment, including mild cognitive impairment (MCI) and early Alzheimer's disease (AD). METHODS: We recruited healthy subjects from our community-based cohort and consecutive subjects with MCI and AD from our clinic. The TMIG-IC was investigated in all participants and their family members. The total and subscale scores were compared among all groups. We then statistically determined the accuracy of the differentiation of MCI and AD. RESULTS: We registered 187 normal controls (NC), 39 participants with MCI, 50 AD patients with functional assessment staging (FAST) 4, and 19 AD patients with ≥5 FAST. The family-report score was significantly lower in MCI patients than in others, followed by AD patients. The total score was able to differentiate MCI and AD with a sensitivity of 85.7% and a specificity of 90.9% (area under the curve [AUC]=0.913). Differentiation of MCI alone had a low accuracy (AUC=0.787). However, the AUC was 0.847 when only the items with inconsistent responses between self and family reports were used as indices. CONCLUSIONS: The TMIG-IC is a useful tool for evaluating the severity of AD, including early AD. These findings suggest that family-report scores can differentiate MCI and AD from cognitive normal aging with a sufficient degree of accuracy. It was also suggested that inconsistencies between self and family reports were higher when differentiating MCI than the self- and family-reports.


Assuntos
Doença de Alzheimer/diagnóstico , Disfunção Cognitiva/diagnóstico , Testes Neuropsicológicos , Família , Humanos , Autorrelato , Sensibilidade e Especificidade
10.
Dent Mater J ; 39(2): 181-186, 2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32037383

RESUMO

The molecular precursor method is an easy and simple method for coating thin carbonate-containing apatite (CA) films onto titanium surfaces. A molecular precursor solution containing ethanol, calcium-EDTA complex, and phosphate salt was dropped onto a titanium surface and then heated at 600°C for 2 h. An adherent thin CA coating was achieved. Animal implantation experiments showed that CA-coated implants had significantly higher bone-to-implant values than non-coated implants (p<0.05). The molecular precursor method was also used to coat three-dimensional titanium webs (TWs). Thin CA films could be coated inside the center area, as well as the surface of the TW, with excellent bone formation inside the CA-coated TW. Furthermore, the molecular precursor method was used to coat partially stabilized zirconia with CA. Better bone response was observed for CA-coated zirconia. From this, it is concluded that the molecular precursor method is useful for producing thin CA coatings on implant materials.


Assuntos
Implantes Dentários , Animais , Apatitas , Carbonatos , Materiais Revestidos Biocompatíveis , Propriedades de Superfície , Titânio
11.
Nihon Ronen Igakkai Zasshi ; 56(3): 273-282, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31366748

RESUMO

AIM: Memorization comprises three stages: encoding, storage, and retrieval. Using neuropsychological tests, we investigated the stage at which encoding and storage are retained in Alzheimer's disease (AD) patients with progressive memory disorder. METHODS: The target patients were an amnestic mild cognitive impairment (MCI) group (21 cases) and FAST 4 (37 cases), 5 (10 cases), and 6 (4 cases) AD groups. The neuropsychological tests performed were the Rivermead behavioral memory test and Wechsler memory scale-revised. These were carried out in the MCI group as well as in each AD stage group. We investigated the delayed recall (free recall and cued recall) based on the disease stage and raw score of the sub-items in delayed recognition. RESULTS: The MCI group had 48% (median 0 point) correct respondents (providing ≥1 correct answer) for free recall, whereas FAST 4 and 5 groups had ≤14% correct respondents. In the verbal paired associates II evaluated in cued recall, the MCI group had 90% correct respondents, and the FAST 4, 5, and 6 groups had rates of 51%, 60%, and 50%, respectively. For the pictures and photos in the delayed recognition tasks, there were no significant differences in the percentage of correct respondents between the MCI group (100%) and the FAST 4 and 5 groups (70%-90%). CONCLUSIONS: Given that retrieval is impossible if encoding and storage are impaired, we inferred that the encoding and retrieval abilities were retained even in moderately advanced AD.


Assuntos
Doença de Alzheimer , Memória , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino
12.
Materials (Basel) ; 12(3)2019 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-30678036

RESUMO

Photo-induced super-hydrophilic thin films were fabricated on a quartz glass substrate by ultraviolet (UV) irradiation of a molecular precursor film at room temperature. A molecular precursor film exhibiting high solubility to both ethanol and water was obtained by spin-coating a solution involving a Ti(IV) complex; this complex was prepared by the reaction of Ti(IV) alkoxide with butylammonium hydrogen oxalate and hydrogen peroxide in ethanol. Transparent and well-adhered amorphous thin films of 160⁻170 nm thickness were obtained by weak UV irradiation (4 mW·cm-2 at 254 nm) of the precursor films for over 4 h at room temperature. The resultant thin films exhibiting low refractive indices of 1.78⁻1.79 were mechanically robust and water-insoluble. The chemical components of the thin films were examined by means of Fourier transform-infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS) spectra, focusing on the presence of the original ligands. The super-hydrophilic properties (evaluated based on the water contact angles on the surfaces) of the thin films after being kept in a dark condition overnight emerged when the aforementioned UV-light irradiation was performed for 10 min. It was additionally clarified that the super-hydrophilicity can be photo-induced repeatedly by UV irradiation for 10 min (indicated by a contact angle smaller than 4°) even after the hydrophilic level of the thin films had once been lowered by being in a dark condition for 4 h.

13.
Int J Stroke ; 14(3): 290-297, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30299228

RESUMO

BACKGROUND: Recent advances in high-resolution (HR) magnetic resonance angiography (MRA) using ultrahigh-field systems enable direct visualization of the lenticulostriate arteries (LSAs), which had been hardly achieved by conventional MRA. Hence, by using HR-MRA at 7 T, we attempted to assess occlusive changes in the LSAs in patients with LSA territorial infarcts. METHODS: We prospectively examined 34 consecutive patients with acute ischemic stroke in the LSA territory using a 7 T scanner. We measured the lengths of the relevant LSAs on HR-MRA and the diameters/volume of the infarcts and compared these between the patients with/without occlusive changes in the LSAs. RESULTS: On HR-MRA, occlusion of the LSAs was observed in 19 (59%) of 32 patients who were eligible for the analyses. The curved/straight lengths of the LSAs in the patients with LSA occlusion (23.1-31.1/17.8-24.3 mm) were significantly shorter than in those without apparent LSA occlusion (25.8-39.5/24.0-30.4 mm) ( P = 0.027/0.003). The anteroposterior/superoinferior diameters of the infarcts were significantly larger in the occluded-LSA group (14.5-21.4/14.9-22.2 mm) than in the intact-LSA group (10.9-16.8/10.8-16.2 mm) ( P = 0.041/0.011). In addition, the curved lengths of the relevant LSAs showed significant correlations with the superoinferior diameters of the infarcts ( r = 0.38, P = 0.034). CONCLUSION: Occlusive changes in the LSAs were frequently found in patients with acute ischemic stroke within the LSA territory when using HR-MRA at 7 T and were substantially related to superoinferior extension of the infarcts.


Assuntos
Gânglios da Base/diagnóstico por imagem , Isquemia Encefálica/diagnóstico , Artérias Cerebrais/diagnóstico por imagem , Angiografia por Ressonância Magnética/métodos , Acidente Vascular Cerebral/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
Intern Med ; 58(1): 123-126, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30146606

RESUMO

The cervical carotid artery has been reported to show anatomical variations. We report the case of a young stroke patient with a small right-parietal-lobe infarction whose cervical carotid artery showed anatomical variation. The right internal carotid artery (ICA) originated at the C2 level of the external carotid artery with protrusion at the right carotid bifurcation. The vessel wall of the protrusion showed a high signal intensity on T1-weighted magnetic resonance carotid plaque imaging. The protrusion, considered a remnant of the ICA, possibly caused the stroke due to the formation of thrombi as a result of changes in blood flow and viscosity.


Assuntos
Artéria Carótida Externa/anormalidades , Artéria Carótida Interna/anormalidades , Estenose das Carótidas/etiologia , Acidente Vascular Cerebral/etiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
15.
Materials (Basel) ; 10(12)2017 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-29232914

RESUMO

We performed thin carbonate-containing apatite (CA) coating on titanium (Ti) by an aqueous spray coating (ASC) method that consisted of a Ca-CO3-PO4 complex. Two different CA coatings were produced by two different spray amounts and were heat-treated after spraying. We evaluated three-dimensional structures, adhesiveness to Ti, and durability of the CA film. In addition, we performed immersion experiments in simulated body fluid (SBF), and bone responses were evaluated after implantation into a femoral bone defect in rats. The bonding ability of ASC-coated implant into the bone was examined by push-in tests. Unique network structures with small particles were identified on CA coatings. Although heat treatment produced no significant difference in surface morphology, scratch tests revealed that heat treatment improved the adhesion of CA coatings to Ti. Crystal formation progressed on CA-coated specimens, and the sample placement direction influenced crystal formation and growth in SBF immersion. Animal implantation experiments revealed significantly greater bone-to-implant contact ratio and bone mass in both cortical and bone marrow, respectively, four weeks after implantation. Push-in tests suggested that the bonding of the CA coating to Ti is clinically acceptable. Therefore, we conclude that CA coating to Ti by the ASC method would be possible for clinical applications, including dentistry.

16.
Biomaterials ; 75: 223-236, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26513415

RESUMO

Coating biomaterials with a thin hydroxyapatite (HA) was proven effective in enhancing bone compatibility. Segmental bone defects are considered as the most difficult defect to repair in bone regeneration therapy. We developed submicron-thin HA-coated titanium fiber mesh scaffolds to reconstruct immediately loaded segmental mandibular defects and evaluated their bone compatibility in vitro and in vivo. Human osteoblasts attachment, proliferation, and osteocalcin expression in non- and HA-coated scaffolds were evaluated. A 10-mm long segmental bone defect in a rabbit mandibular bone was reconstructed with non- or HA-coated scaffolds, which were removed at 9 and 21 weeks, to evaluate the mechanical strength of the bone-scaffold connection and the bone formation around the scaffold. Expression of osteocalcin was greater in HA-coated scaffolds. In vivo bone formation in HA-coated scaffolds was greater than that in non-coated scaffolds at 21 weeks. Newly formed bone in HA-coated scaffolds mostly restored bone continuity. Scanning electron microscopy identified strong integration of the bone and HA-coated scaffolds. The mechanical strength of the bone-scaffold connection was 3-fold greater in HA-coated scaffolds than that in non-coated scaffolds. These results suggest that a thin HA-coated titanium fiber mesh scaffold is a bone-compatible mandibular reconstruction device in immediately loaded segmental defects.


Assuntos
Mandíbula/cirurgia , Reconstrução Mandibular/instrumentação , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Titânio/farmacologia , Animais , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/farmacologia , Durapatita/farmacologia , Humanos , Masculino , Mandíbula/anatomia & histologia , Mandíbula/diagnóstico por imagem , Mandíbula/ultraestrutura , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Coelhos , Microtomografia por Raio-X
17.
Value Health Reg Issues ; 6: 126-129, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-29698183

RESUMO

In Asia-Pacific countries, as elsewhere, medical device expenditures account for only between 3% and 6% of total health care spending per capita. Yet the contribution of medical devices is essential to delivering improved clinical and economic benefits for patients and health care systems, respectively. We briefly report a selective overview of reimbursement coverage and pricing systems for single-use devices (SUDs) in Japan, Taiwan, Korea, and Australia, major Asia-Pacific markets with diverse health care systems but similar challenges. Generally speaking, all four health systems are similar in their framework for managing the coverage and reimbursement of SUDs, which are usually bundled into the overall fee designated for a surgical procedure; however, funding guidelines are unclear and decision-making processes opaque. Unfortunately, this inequitable situation encourages both the dangerous practice of reuse of devices and the imposition of additional out-of-pocket costs on patients. Reimbursement pathways in all four countries need to evolve to accommodate new methods of delivering health care, with fair decision-making processes for reimbursement coverage and pricing, which assess the overall value of medical devices, including SUDs, in terms of health outcomes and/or safety.

18.
Mater Sci Eng C Mater Biol Appl ; 39: 245-52, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24863222

RESUMO

Four carbonated apatite films having average thicknesses of 1.3-0.11µm, proportions of network sizes above 10µm of 41-68%, and average border heights of the characteristic network structure of 0.98-0.29µm were fabricated on a titanium plate by aqueous spray coating. These carbonated apatite films after heat treatment showed good mineralization ability in Hanks' balanced salt solution. Assessment of initial cell attachment and calcination on these films and on the Ti plate using osteoblastic MC3T3-E1 indicated that the carbonated apatite film heat treated at 600°C, whose film thickness, proportion of network sizes above 10µm, and border height were 0.11µm, 61%, and 0.31µm, respectively, was most preferred by osteoblastic cells. Field emission scanning electron microscopic observation of the cells attached to the films showed that the wide network and low border height of the network structure on the carbonated apatite film play an important role in the development of the filopodia of the osteoblastic cells.


Assuntos
Apatitas/química , Titânio/química , Células 3T3 , Animais , Proliferação de Células/efeitos dos fármacos , Camundongos , Microscopia Eletrônica de Varredura , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Propriedades de Superfície
19.
Dent Mater J ; 33(1): 39-47, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24492110

RESUMO

The influence of a thin carbonate-containing hydroxyapatite (CA) coating to tetragonal zirconia polycrystal (TZP) on osteoblastlike cell response was investigated. TZP disks were subjected to blasting and acid etching. Thin CA coatings were deposited by the molecular precursor method (TZP-CA). Initial cell adhesion of mouse osteoblast-like cells MC3T3-E1 was enhanced, and marked progress of actin filaments was observed on TZP-CA compared to on TZP. After 3, 5 or 7 days, cell proliferation on TZP-CA was significantly higher than that on TZP. Alkaline phosphatase activity was slightly lower on TZP-CA than on TZP at 7 days, and no difference was observed at 14 or 21 days. At 28 days incubation, collagenous fibers with mineral precipitants accompanied by phosphorous and amino groups were observed. These results indicate that thin CA coating with molecular precursor method offers promise as a means of enhancing cell response, particularly initial adhesion and proliferation of MC3T3-E1 cells.


Assuntos
Apatitas/química , Materiais Revestidos Biocompatíveis/química , Osteoblastos/fisiologia , Zircônio/química , Condicionamento Ácido do Dente , Actinas/fisiologia , Fosfatase Alcalina/metabolismo , Animais , Adesão Celular , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Teste de Materiais , Camundongos , Propriedades de Superfície
20.
J Biomed Mater Res B Appl Biomater ; 102(6): 1277-88, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24449291

RESUMO

Thin carbonate-containing hydroxyapatite (CA) films coating partially stabilized zirconia (Y-TZP) were prepared (CA-Y-TZP) to establish a metal-free implant system. CA was coated using a molecular precursor method. The CA film was deposited on the surface of Y-TZP using a precursor solution, which was a mixture of a calcium-ethylenediaminetetraacetic acid (EDTA) complex and phosphate compounds. The deposited CA film was characterized by X-ray diffraction, Fourier transform infrared spectroscopy, and energy dispersive X-ray spectroscopy measurements. A focus ion beam system technique revealed that the thickness of the CA film was less than 1.0 µm. Biological evaluations of CA-Y-TZP were performed by immersion experiments in simulated body fluid (SBF) and implantation experiments in the tibiae and femoral condyles of rabbits. In the SBF immersion experiment, apatite deposition progressed more on CA-Y-TZP at the early stage of immersion than on Y-TZP without the CA coating. Animal experiments revealed that bone formation on CA-Y-TZP was similar with than on Y-TZP. Histomorphometrical evaluations showed a significantly higher bone-to-implant contact ratio and bone mass on CA-Y-TZP after implantation into the femoral trabecular bone of rabbits. Therefore, CA-Y-TZP appears to be applicable as a metal-free implant.


Assuntos
Substitutos Ósseos , Carbonatos , Materiais Revestidos Biocompatíveis , Durapatita , Osteogênese/efeitos dos fármacos , Zircônio , Animais , Substitutos Ósseos/química , Substitutos Ósseos/farmacologia , Carbonatos/química , Carbonatos/farmacologia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Durapatita/química , Durapatita/farmacologia , Feminino , Teste de Materiais/métodos , Coelhos , Zircônio/química , Zircônio/farmacologia
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