Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 349
Filtrar
1.
Neurosurg Rev ; 47(1): 80, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38355838

RESUMEN

Retrospective observational study. To determine the efficacy and safety of bioactive glass ceramics mixed with autograft in the treatment of spondylodiscitis. Thirty-four patients with spondylodiscitis underwent surgery using autologous bone graft augmented by antibiotic loaded bioactive glass ceramic granules. Twenty-five patients aging 6 to 77, completed 1-year follow-up. The lumbosacral junction was affected in 3, lumbar spine in 13, one each in the dorso-lumbar junction and sacrum, and 7 dorsal spines. The organism isolated was Mycobacterium tuberculosis in 15, Methicillin sensitive Staphylococcus aureus (MSSA) in 4, Pseudomonas aeruginosa in 4, Klebsiella pneumoniae in one, Burkholderia pseudomallei in 1, and mixed infections in 2. All patients had appropriate antibiotic therapy based on culture and sensitivity. Clinical and radiological evaluation of all the patients was done at 6 weeks, 3 months, 6 months, and 12 months after the surgery. Twenty-three patients improved clinically and showed radiographic fusion between 6 and 9 months. The patient with Burkholderia infection died due to fulminant septicemia with multi organ failure while another patient died at 9 months due to an unrelated cardiac event. The mean Visual Analogue Score (VAS) at the end of 1-year was 2 with radiological evidence of fusion in all patients. There were no re-infections or discharging wounds, and the 30-day re-admission rate was 0. Bioactive glass ceramics is a safe and effective graft expander in cases of spondylodiscitis. The absorption of antibiotics into the ceramic appears to help the elimination of infection.


Asunto(s)
Discitis , Fusión Vertebral , Humanos , Cerámica/efectos adversos , Cerámica/uso terapéutico , Discitis/cirugía , Discitis/microbiología , Vértebras Lumbares/cirugía , Proyectos Piloto , Radiografía , Estudios Retrospectivos , Resultado del Tratamiento , Niño , Anciano
2.
J Dent ; 142: 104832, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38211687

RESUMEN

OBJECTIVES: The aim of this study was to evaluate the amount of enamel tooth wear induced by different antagonistic ceramic crown materials in the posterior area within a follow-up period up to 24 months in function. A network meta-analysis was performed to assess the effect of the materials on the mean vertical loss (MVL) of the antagonist enamel tooth surface. DATA: Main search terms used in combination: ceramic, dental materials, metal ceramic, tooth wear and dental enamel. SOURCES: An electronic search was conducted in PubMed/Medline, Embase, and Cochrane CENTRAL plus hand-searching. STUDY SELECTION: Eligibility criteria included clinical studies reporting on MVL on antagonist's tooth up to 24 months following the permanent crown placement. From a total of 5697 articles, 7 studies reporting on 261 crowns for 177 subjects with 3 ceramic materials (Lithium disilicate, metal-ceramic, monolithic zirconia) were included. Among all, metal-ceramic and zirconia caused significantly higher enamel tooth wear on antagonist teeth, representing 82.5 µm [54.4; 110.6]) and 40.1 µm [22.2; 58.0]) more MVL than natural teeth group. In contrast, lithium disilicate showed only 5.0 µm [-48.2; 58.1]) more MVL than occurs on opposing natural teeth. CONCLUSIONS: This systematic review demonstrated that prosthodontic ceramic materials produced significantly more antagonist enamel tooth wear than opposing natural enamel tooth wear, and ceramic material type was correlated to the degree of enamel tooth wear. Additional well-conducted, randomized controlled trials with homogeneous specimens are required due to inadequate sample size and number of the clinical studies included in the analyses. CLINICAL SIGNIFICANCE: The amount of wear caused by different restorative materials has a high influence on the antagonistic natural teeth and should therefore be evaluated intensively by the dentist.


Asunto(s)
Esmalte Dental , Desgaste de los Dientes , Humanos , Cerámica/efectos adversos , Coronas , Porcelana Dental/efectos adversos , Alisadura de la Restauración Dental , Ensayo de Materiales , Metaanálisis en Red , Propiedades de Superficie , Desgaste de los Dientes/etiología , Circonio/efectos adversos , Ensayos Clínicos Controlados como Asunto
3.
Br Dent J ; 232(9): 611-614, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35562452

RESUMEN

Restorative dental materials are among the most important medical devices in terms of the numbers of patients who benefit and the technical sophistication of the products. Many though contain toxic or noxious substances, including potentially sensitising resin monomers, photoinitiators, acidic polymers and glass or ceramic filler particles. Despite this, dental materials are among the safest medical devices in use today, with very few reports of adverse reactions or injuries among both patients or the dental team. This paper considers the potential for adverse reactions to dental materials, current evidence for harm and finally examines the reasons why in real-world clinical use the likelihood of an adverse event is extremely low. Medical devices regulations, responsible manufacture and clinical vigilance all appear to play important roles in ensuring that dental materials do not cause or present a risk to patients. While this excellent in-practice safety record is welcome, there is now increasing interest in the 'macro' scale biocompatibility of dental materials and their packaging in the environment, subjects that have been relatively neglected until recently. It was concluded that this should be a priority for future research and development and support is needed from governments alongside the manufacturing industry and the profession.


Asunto(s)
Resinas Compuestas , Estética Dental , Cerámica/efectos adversos , Materiales Dentales/efectos adversos , Restauración Dental Permanente/efectos adversos , Humanos
4.
Int J Mol Sci ; 22(16)2021 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-34445136

RESUMEN

In this research we subjected samples of poly(L-lactide) (PLLA) extruded film to ultraviolet (193 nm ArF excimer laser) radiation below the ablation threshold. The modified film was immersed in Simulated Body Fluid (SBF) at 37 °C for 1 day or 7 days to obtain a layer of apatite ceramic (CaP) coating on the modified PLLA surface. The samples were characterized by means of optical profilometry, which indicated an increase in average roughness (Ra) from 25 nm for the unmodified PLLA to over 580 nm for irradiated PLLA incubated in SBF for 1 day. At the same time, the water contact angle decreased from 78° for neat PLLA to 35° for irradiated PLLA incubated in SBF, which suggests its higher hydrophilicity. The obtained materials were investigated by means of cell response fibroblasts (3T3) and macrophage-like cells (RAW 264.7). Properties of the obtained composites were compared to the unmodified PLLA film as well as to the UV-laser irradiated PLLA. The activation of the PLLA surface by laser irradiation led to a distinct increase in cytotoxicity, while the treatment with SBF and the deposition of apatite ceramic had only a limited preventive effect on this harmful impact and depended on the cell type. Fibroblasts were found to have good tolerance for the irradiated and ceramic-covered PLLA, but macrophages seem to interact with the substrate leading to the release of cytotoxic products.


Asunto(s)
Cerámica/efectos adversos , Cerámica/química , Poliésteres/efectos adversos , Poliésteres/química , Células 3T3 , Animales , Apatitas/efectos adversos , Apatitas/química , Materiales Biocompatibles/efectos adversos , Materiales Biocompatibles/química , Línea Celular , Fibroblastos/efectos de los fármacos , Rayos Láser , Ratones , Prótesis e Implantes/efectos adversos , Células RAW 264.7 , Propiedades de Superficie , Rayos Ultravioleta
5.
Rev. cuba. estomatol ; 58(2): e3265, 2021. tab, graf
Artículo en Español | LILACS, CUMED | ID: biblio-1289407

RESUMEN

Introducción: Gracias a su eficiencia y al uso exclusivo de cerámicas libres de metal, en rehabilitación oral se ha logrado alcanzar los estándares estéticos y mecánicos, manteniendo o, incluso, superando, la calidad de los tratamientos en comparación con las restauraciones metal cerámicas tradicionales. Actualmente los mecanismos de confeccion de cerámica libre están evolucionando cada vez mas hacia las tecnologías maquinadas CAD-CAM y disminuyendo su producción mediante la técnica de Inyeccion PRESS. Objetivo: Comparar la tasa de supervivencia de prótesis fija unitaria realizadas con cerámicas feldespáticas convencionales y reforzadas con disilicato de litio, confeccionadas con sistema CAD/CAM de CEREC® chair-side, en comparación con el método de inyección de laboratorio PRESS convencional de prensión. Métodos: Revisión sistemática realizada a través de búsqueda de evidencia científica en PubMed, PubMed Clinical Queries, Epistemónikos, Tripdatabase, Cochrane Library, recursos electrónicos de la Universidad de los Andes y bibliografía retrógrada, de artículos publicados hasta el año 2019. Se incluyeron todos aquellos estudios referentes a prótesis fija unitaria de cerámicas feldespática convencional y feldespática reforzada con disilicato de litio, confeccionadas mediante CAD/CAM y/o método convencional. Resultados: Un total de 28 artículos cumplieron los criterios de inclusión: 21 estudios observacionales de cohorte, 4 ensayos clínicos aleatorizados y 3 no aleatorizados. A corto y mediano plazo, CAD/CAM de CEREC® registró tasas de supervivencia de 98 por ciento y 91,9 por ciento, respectivamente. El sistema convencional registró tasas de supervivencia de 97,5 por ciento a corto plazo y 93 por ciento a mediano. Conclusiones: A corto plazo se describe en la literatura que CAD/CAM de CEREC® tuvo una tasa de supervivencia ligeramente superior al sistema convencional. Por otro lado, a mediano plazo CAD/CAM de CEREC® presentó una leve disminución respecto al sistema convencional. Aún no hay estudios disponibles para determinar la supervivencia clínica de los tratamientos a largo plazo(AU)


Introduction: Thanks to its efficiency and the exclusive use of metal-free ceramics, in oral rehabilitation it has been possible to achieve aesthetic and mechanical standards, maintaining or even exceeding the quality of the treatments compared to traditional metal-ceramic restorations. Currently, free ceramic manufacturing mechanisms are increasingly evolving towards CAD-CAM machined technologies and decreasing their conventional production through the PRESS Injection technique. Objective: Compare the survival rate of single-unit fixed prostheses made with conventional feldspathic ceramics and reinforced with lithium disilicate by the CEREC® CAD/CAM chairside system, with the conventional PRESS laboratory injection method. Methods: A systematic review was conducted of scientific evidence included in papers published until the year 2019 in PubMed, PubMed Clinical Queries, Epistemonikos, Tripdatabase, Cochrane Library, electronic resources of Los Andes Peruvian University, and retrograde bibliography. The papers selected dealt with conventional and lithium-disilicate reinforced feldspathic ceramic single-unit prostheses made by CAD/CAM and/or the conventional method. Results: A total 28 papers met the inclusion criteria. Of these, 21 were observational cohort studies, four were randomized clinical assays and three were non-randomized assays. Short- and mid-term, CEREC® CAD/CAM achieved survival rates of 98 percent and 91.9 percent, respectively. The conventional system achieved survival rates of 97.5 percent short-term and 93 percent mid-term. Conclusions: As described in the literature, CEREC® CAD/CAM had a slightly higher survival rate than the conventional system in the short term. In the medium term, however, CEREC® CAD/CAM displayed a slight reduction in comparison with the conventional system. No studies are available to determine the clinical survival of the treatments in the long term(AU)


Asunto(s)
Humanos , Cerámica/efectos adversos , Diseño de Prótesis Dental/métodos , Diseño Asistido por Computadora/tendencias , Dentadura Parcial Fija/efectos adversos , Literatura de Revisión como Asunto , Tasa de Supervivencia , Estudios de Cohortes , Estudios Observacionales como Asunto , Estética Dental
6.
ScientificWorldJournal ; 2021: 5561040, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34035672

RESUMEN

METHODS: The current study includes 80 extracted premolars of human from the patient visiting for orthodontic treatment of Coorg Institute of Dental Sciences, Karnataka, India. The brackets were debonded using four different methods. The enamel surface damage after the procedure was assessed with the Enamel Surface Index (ESI); similarly, the Adhesive Remnant Index (ARI) score was used to determine the adhesive residual deposit. Scanning electron microscopy (SEM) was used to visualize better microporosities and micromechanical retention of adhesive remnants on the enamel surface. The normality of the data was tested using the Kolmogorov-Smirnov test. Depending upon the normality test result, the one-way ANOVA test or Kruskal-Wallis test was used to test the mean ESI and mean ARI differences among different debonding methods along with the appropriate post hoc tests. The necessary ethical clearance was obtained from the Ethics Committee of the institute. RESULTS: The ultrasonic scaler (US) technique led to more significant enamel surface damage, with 13 (65%) samples in the ESI scores III and IV against the satisfactory surface in 2 (10%) samples with the ligature cutter (LC) technique (ESI-I) reflecting LC as a better technique. The ESI scores (III and IV) for debonding plier (DP) and thermal method (TM) reflected a higher value in 12 (60%) and 10 (50%) samples and caused more damage to the enamel surface as compared to the LC technique. The ARI score was highest (ARI-1 = 40%) with the LC technique, followed by the US (ARI-1 = 20%), TM (ARI-1 = 15%), and DP (ARI-1 = 5%) methods. We have observed a significant association (p value <0.05) of the ARI score among four different debonding ways in terms of each tooth's residual adhesive after the bracket removal. CONCLUSION: The result establishes the LC technique as a more acceptable one as it causes minimal harm to the debonded surface. The adhesive left on the debonded area is also minimum as compared to the other three methods tested. Therefore, it can be suggested as an ideal method.


Asunto(s)
Cerámica/efectos adversos , Desconsolidación Dental , Esmalte Dental/lesiones , Soportes Ortodóncicos/efectos adversos , Cerámica/uso terapéutico , Desconsolidación Dental/efectos adversos , Desconsolidación Dental/métodos , Humanos , Microscopía Electrónica de Rastreo
7.
Sci Rep ; 11(1): 5539, 2021 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-33692436

RESUMEN

This study aimed to evaluate (1) the overall reasons for first revision in CoC THAs; (2) whether the reasons for revision differ between third-generation and fourth-generation CoC THAs; and (3) the specific factors associated with bearing-related problems as the reason for revision. We retrospectively reviewed 2045 patients (2194 hips) who underwent first revision THA between 2004 and 2013, among which 146 hips with CoC bearings underwent revision. There were 92 hips with third-generation ceramic bearings and 54 hips with fourth-generation ceramic bearings. The major reasons for CoC THA revisions were ceramic fracture and loosening of the cup or stem. When ceramic fracture, squeaking, incorrect ceramic insertion, and unexplained pain were defined as directly related or potentially related to ceramic use, 28.8% (42/146) of CoC revisions were associated with bearing-related problems. Among the third-generation ceramic bearings, revision was performed in 41.3% (38/92) of cases owing to bearing-related problems whereas revisions were performed for only 7.4% (4/54) of cases with fourth-generation ceramic bearings owing to bearing-related problems (p < 0.001). Younger age, lower American Society of Anesthesiologists (ASA) grade, and preoperative diagnosis of osteonecrosis were factors related to CoC THA revisions due to bearing-related problems.


Asunto(s)
Artroplastia de Reemplazo de Cadera/efectos adversos , Cerámica/efectos adversos , Prótesis de Cadera/efectos adversos , Osteonecrosis/epidemiología , Complicaciones Posoperatorias/epidemiología , Falla de Prótesis , Sistema de Registros , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteonecrosis/etiología , Factores de Riesgo , Factores de Tiempo
8.
Arch Orthop Trauma Surg ; 141(7): 1155-1162, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32529389

RESUMEN

BACKGROUND: The results of total hip arthroplasty (THA) with use of Delta ceramic articulation were successful at medium term follow-up. The use of this newest ceramic has markedly reduced the incidence of ceramic head fractures, but not the incidence of ceramic liner fractures. We tested a hypothesis that the ceramic fractures are prevented by use of a metal shell with 18° inner taper angle and a stem design with a reduced neck geometry. METHODS: We conducted a prospective multicenter study of cementless THA with use of 32/36-mm Delta ceramic bearing, Exceed ABT metal shell and Taperloc stem. We evaluated ceramic fracture, noise, clinical results, radiological changes and survival rate at a minimum of 5-year follow-up. RESULTS: From April 2010 to February 2012, 246 patients (274 THAs) were enrolled. Among them, 224 patients (130 men and 94 women, 250 hips) were followed-up for 5-8 years (mean 6.0 years). Ceramic malseating or fracture did not occur in any patient. Eight patients (8 hips, 3.2%) reported noise. Mean Harris hip score was 84 points at the latest follow-up. All acetabular and femoral components had bone-ingrown stability. Two hips were revised due to recurrent dislocation and periprosthetic fracture. The survival rate was 99.6% at 8 years postoperatively. CONCLUSION: Ceramic fractures can be prevented by a use of (1) 32/36-mm Delta ceramic bearing, (2) metal shell with 18° taper angle, and (2) stem with a reduced neck geometry. However, noise remains a concern of the Delta ceramic bearing. LEVEL OF EVIDENCE: Therapeutic level II.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Cerámica/efectos adversos , Prótesis de Cadera/efectos adversos , Complicaciones Posoperatorias/prevención & control , Falla de Prótesis , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Cadera/instrumentación , Humanos , Estudios Prospectivos , Diseño de Prótesis , Resultado del Tratamiento
9.
BMC Musculoskelet Disord ; 21(1): 670, 2020 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-33036595

RESUMEN

BACKGROUND: Highly cross-linked polyethylene (HXLPE) enhances the anti-wear characteristics of the conventional polyethylene (PE). Early failure for wear after ceramic-on-highly cross-linked polyethylene (CoHXLPE) total hip arthroplasty (THA) is extremely rare. CASE PRESENTATION: We described the case of a 60-year-old man who underwent right CoHXLPE THA because of the developmental dysplasia hip (DDH) complained pain 32 months after this procedure. Plain radiographs showed that eccentric wear existed at the polyethylene insert. However, the patient refused surgery at that time and did not stop weight-bearing. The right hip pain continued for 7 months. Plain radiographs of the pelvis showed that the HXLPE liner was penetrated and partial inner wall of acetabular shell was worn. Acetabular cup revision was performed, and the ceramic head and HXLPE were exchanged. CONCLUSIONS: Difficult reduction during primary THA, especially for DDH, can result in higher abductor tension, which may lead to early eccentric wear of the prosthesis. Whenever eccentric wear of HXLPE liner was found, weight-bearing must be stopped to avoid the accelerated wear and adverse reactions to metal debris (ARMD).


Asunto(s)
Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Artroplastia de Reemplazo de Cadera/efectos adversos , Cerámica/efectos adversos , Prótesis de Cadera/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Polietileno/efectos adversos , Diseño de Prótesis , Falla de Prótesis
10.
PLoS One ; 15(10): e0240613, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33075091

RESUMEN

BACKGROUND: Identifying the functional materials inside vaping devices can help inform efforts to understand risk. While nicotine E-cigarette components and metals have been characterized in several previous studies, the internal component compositions of tetrahydrocannabinol (THC) cartridge designs are not as well known. The 2019-20 e-cigarette or vaping product use associated lung injury (EVALI) outbreak has been associated with THC devices containing vitamin E acetate (VEA), possibly mediated by chemical reactions with internal cartridge components and high filament temperatures. METHODS: We investigate the composition and internal components of 2019 EVALI patient-associated THC vaping devices compared to other THC and nicotine devices from 2016-19, specifically the metal, ceramic, and polymer components likely to be exposed to heat. To do this, we have disassembled forty-eight components from eight used and unused vaping devices under a microscope and analyzed them using X-ray fluorescence, scanning electron microscopy, and Fourier-transform infrared micro-spectroscopy. CONCLUSIONS: The two THC cartridges used by EVALI patients exhibited evidence of localized high temperatures, including charring of the ceramic heating elements and damaged wire surfaces. The newer THC cartridges possessed more ceramic and polymer insulation than older THC or nicotine devices. The combination of ceramics, metals, and high temperatures in newer THC cartridges is consistent with conditions hypothesized to produce VEA reactions during vaping. Nickel and chromium components were detected in all devices, and others contained copper, lead, tin, gold, silicon-rich rubbers, or fluorinated microplastics. These components have the potential to thermally degrade and volatilize if heated sufficiently. These findings do not imply that harmful exposures would occur under all usage conditions, and are most relevant to harm reduction efforts based on avoiding higher internal temperatures. This study was limited to a small sample of cartridges obtained from investigations. Future work should test more device types and internal temperatures under controlled usage conditions.


Asunto(s)
Dronabinol/efectos adversos , Sistemas Electrónicos de Liberación de Nicotina , Lesión Pulmonar/patología , Nicotina/química , Cannabinoides/toxicidad , Cerámica/efectos adversos , Cerámica/química , Brotes de Enfermedades , Dronabinol/química , Calor/efectos adversos , Humanos , Lesión Pulmonar/inducido químicamente , Lesión Pulmonar/epidemiología , Microscopía Electrónica de Rastreo , Nicotina/efectos adversos , Plásticos/efectos adversos , Polímeros/efectos adversos , Polímeros/química , Goma/efectos adversos , Goma/química , Vapeo/fisiopatología
11.
Int J Mol Sci ; 21(19)2020 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-32993182

RESUMEN

(1) Background: Aluminum oxide (Al2O3) ceramic is one of the materials used for artificial joints, and it has been known that their fine particles (FPs) are provided by the wear of the ceramic. Al2O3 FPs have been shown to induce macrophage activation in vitro; however, the inflammatory effect in vivo has not been studied. (2) Methods: We examined the in vivo effect of Al2O3 FPs on the innate and adaptive immune cells in the mice. (3) Results: Al2O3 FPs promoted the activation of spleen macrophages; however, conventional dendritic cells (cDCs), plasmacytoid DCs (pDCs), and natural killer (NK) cells were not activated. In addition, increases in the CD4 and CD8 T cells was induced in the spleens of the mice treated with Al2O3 FPs, which differentiated into interferon-gamma (IFN-γ)-producing helper T1 (Th1) and cytotoxic T1 (Tc1) cells. Finally, the injection of Al2O3 FPs exacerbated dextran sulfate sodium (DSS)-induced inflammation in the colon, mediated by activated and increased number of CD4 and CD8 T cells. (4) Conclusions: These data demonstrate that FPs of Al2O3 ceramic may contribute to the exacerbation of inflammatory diseases in the patients.


Asunto(s)
Óxido de Aluminio/efectos adversos , Cerámica/efectos adversos , Activación de Linfocitos/efectos de los fármacos , Activación de Macrófagos/efectos de los fármacos , Macrófagos/efectos de los fármacos , Linfocitos T/efectos de los fármacos , Animales , Materiales Biocompatibles/efectos adversos , Inflamación/inducido químicamente , Inflamación/inmunología , Macrófagos/inmunología , Ratones , Ratones Endogámicos C57BL , Tamaño de la Partícula , Linfocitos T/inmunología
12.
Anal Chem ; 92(21): 14432-14443, 2020 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-32970419

RESUMEN

Degradation of the implant surface and particle release/formation as an inflammation catalyst mechanism is an emerging concept in dental medicine that may help explain the pathogenesis of peri-implantitis. The aim of the present study was a synchrotron-based characterization of micro- and nanosized implant-related particles in inflamed human tissues around titanium and ceramic dental implants that exhibited signs of peri-implantitis. Size, distribution, and chemical speciation of the exogenous micro- and nanosized particle content were evaluated using synchrotron µ-X-ray fluorescence spectroscopy (XRF), nano-XRF, and µ-X-ray absorption near-edge structure (XANES). Titanium particles, with variable speciation, were detected in all tissue sections associated with titanium implants. Ceramic particles were found in five out of eight tissue samples associated with ceramic implants. Particles ranged in size from micro- to nanoscale. The local density of both titanium and ceramic particles was calculated to be as high as ∼40 million particles/mm3. µ-XANES identified titanium in predominantly two different chemistries, including metallic and titanium dioxide (TiO2). The findings highlight the propensity for particle accumulation in the inflamed tissues around dental implants and will help in guiding toxicological studies to determine the biological significance of such exposures.


Asunto(s)
Cerámica/efectos adversos , Implantes Dentales/efectos adversos , Microesferas , Nanopartículas , Periimplantitis/inducido químicamente , Periimplantitis/metabolismo , Titanio/efectos adversos , Cerámica/química , Cerámica/metabolismo , Humanos , Tamaño de la Partícula , Titanio/química , Titanio/metabolismo
13.
Chest ; 158(3): 1050-1059, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32298729

RESUMEN

BACKGROUND: Little is known about the different risk of silicosis in metal mines and pottery factories. We aimed to compare the silicosis risks among silica-exposed workers in different industrial circumstances. RESEARCH QUESTION: Are the silicosis risks among silica-exposed workers in industrial circumstances different? STUDY DESIGN AND METHODS: We studied 39,808 workers followed up from January 1, 1960 to December 31, 2003 in China. Cumulative respirable silica dust exposure (CDE) was estimated by linking a job-exposure matrix to personal work history. Silicosis of stage I or higher was diagnosed by Chinese pneumoconiosis Roentgen diagnostic criteria. RESULTS: A total of 9,377 silicosis patients were diagnosed during 1,153,580.9 person-years' follow-up in the cohort. Hazard ratios of silicosis for each 1 mg/m3-year increase in CDE were 1.08 (1.07-1.08) for tungsten mines, 1.41 (1.33-1.48) for iron and copper mines, 1.14 (1.11-1.17) for tin mines, and 1.03 (1.02-1.04) for pottery factories, respectively. When exposed to 0.05 mg/m3 of respirable silica dust for 45 years, the cumulative risks in metal mines (2.3%, 9.9%, 1.5% for tungsten mines, iron and copper mines, and tin mines, respectively) were still higher than those in pottery factories (0.6%). The joint effect of silica and smoking on silicosis was more than multiplicative. INTERPRETATION: The risk of silicosis in metal miners is higher than that in pottery workers when exposed to the same level of silica dust. The silica dust exposed years should be under 10 years for metal miners and 40 years for pottery workers at 0.05 mg/m3 to keep lifetime risk within 0.1%. Current exposure limits should take into account differences in various industrial circumstances. Smoking cessation could help reduce silicosis risk for silica-exposed workers.


Asunto(s)
Cerámica/efectos adversos , Metales , Minería , Exposición Profesional/efectos adversos , Silicosis/etiología , Adulto , China/epidemiología , Polvo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Silicosis/diagnóstico por imagen , Silicosis/epidemiología , Fumar/epidemiología
14.
J Shoulder Elbow Surg ; 29(5): 1019-1029, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31948834

RESUMEN

BACKGROUND: Hemiarthroplasty has clear advantages over alternative procedures and is used in 20% of all shoulder joint replacements. Because of cartilage wear, the clinical outcome of hemiarthroplasty is unreliable and controversial. This paper suggests that the optimal choice of prosthetic material may reduce cartilage degeneration and improve the reliability of the procedure. The specific objectives were to assess 3 materials and assess how the severity of arthritis might affect the choice of prosthetic material. METHODS: A CoCr alloy, an AL2O3 ceramic, and a polycarbonate urethane polymer (PCU) were mechanically tested against 5 levels of human osteoarthritic cartilage (from intact to severely arthritic, n = 45). A high friction coefficient, a decrease in Young's modulus, an increase in permeability, a decrease in relaxation time, an increase in surface roughness, and a disrupted appearance of the cartilage after testing were used as measures of cartilage damage. The biomaterial that caused minimal cartilage damage was defined as superior. RESULTS: The CoCr caused the most damage. This was followed by the AL2O3 ceramic, whereas the PCU caused the least amount of damage. Although the degree of arthritis had an effect on the results, it did not change the trend that CoCr performed worst and PCU the best. DISCUSSION AND CONCLUSION: This study indicates that ceramic implants may be a better choice than metals, and the articulating surface should be as smooth as possible. Although our results indicate that the degree of arthritis should not affect the choice of prosthetic material, this suggestion needs to be further investigated.


Asunto(s)
Cartílago Articular/lesiones , Hemiartroplastia/efectos adversos , Hemiartroplastia/instrumentación , Prótesis de Hombro/efectos adversos , Materiales Biocompatibles/efectos adversos , Cerámica/efectos adversos , Aleaciones de Cromo/efectos adversos , Módulo de Elasticidad , Fricción , Humanos , Ensayo de Materiales , Osteoartritis/diagnóstico por imagen , Poliuretanos/efectos adversos , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad
15.
Sci Rep ; 9(1): 18439, 2019 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-31804544

RESUMEN

This study investigates a comprehensive model of bone regeneration capacity of dypiridamole-loaded 3D-printed bioceramic (DIPY-3DPBC) scaffolds composed of 100% beta-tricalcium phosphate (ß -TCP) in an immature rabbit model through the time of facial maturity. The efficacy of this construct was compared to autologous bone graft, the clinical standard of care in pediatric craniofacial reconstruction, with attention paid to volume of regenerated bone by 3D reconstruction, histologic and mechanical properties of regenerated bone, and long-term safety regarding potential craniofacial growth restriction. Additionally, long-term degradation of scaffold constructs was evaluated. At 24 weeks in vivo, DIPY-3DPBC scaffolds demonstrated volumetrically significant osteogenic regeneration of calvarial and alveolar defects comparable to autogenous bone graft with favorable biodegradation of the bioactive ceramic component in vivo. Characterization of regenerated bone reveals osteogenesis of organized, vascularized bone with histologic and mechanical characteristics comparable to native bone. Radiographic and histologic analyses were consistent with patent craniofacial sutures. Lastly, through application of 3D morphometric facial surface analysis, our results support that DIPY-3DPBC scaffolds do not cause premature closure of sutures and preserve normal craniofacial growth. Based on this novel evaluation model, this DIPY-3DPBC scaffold strategy is a promising candidate as a safe, efficacious pediatric bone tissue engineering strategy.


Asunto(s)
Regeneración Ósea/efectos de los fármacos , Dipiridamol/administración & dosificación , Regeneración Tisular Dirigida/métodos , Cráneo/lesiones , Andamios del Tejido/química , Animales , Bioimpresión/métodos , Fosfatos de Calcio/efectos adversos , Fosfatos de Calcio/química , Cerámica/efectos adversos , Cerámica/química , Niño , Desarrollo Infantil/efectos de los fármacos , Dipiridamol/efectos adversos , Modelos Animales de Enfermedad , Humanos , Desarrollo Maxilofacial/efectos de los fármacos , Modelos Animales , Impresión Tridimensional , Conejos , Cráneo/efectos de los fármacos , Cráneo/crecimiento & desarrollo , Ingeniería de Tejidos/métodos , Andamios del Tejido/efectos adversos
16.
Orthop Surg ; 11(5): 770-776, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31464084

RESUMEN

OBJECTIVE: Wear-induced aseptic loosening has been accepted as one of the main reasons for failure of total hip arthroplasty. Ceramic wear debris is generated following prosthesis implantation and plays an important part in the upregulation of inflammatory factors in total hip arthroplasty. The present study investigates the influence of ceramic debris on osteoblasts and inflammatory factors. METHODS: Ceramic debris was prepared by mechanical grinding of an aluminum femoral head and added to cultures of MC3T3-E subclone 14 cells at different concentrations (i.e. 0, 5, 10, and 15 µg/mL). Cell proliferation was evaluated using a Cell Counting Kit (CCK-8), and cell differentiation was assessed by mRNA expression of alkaline phosphatase (ALP), osteocalcin (OCN), and osteopontin (OPN). In addition, cell bio-mineralization was evaluated through alizarin red S staining, and release of tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1ß), and interleukin-6 (IL-6) was measured through enzyme-linked immunosorbent assays (ELISA). Furthermore, mRNA expression of Smad1, Smad4, and Smad5 and protein expression of phosphorylated Smad1, Smad4, and Smad5 were measured by reverse transcriptase polymerase chain reaction (RT-PCR) and western blotting. RESULTS: The ceramic debris had irregular shapes and sizes, and analysis of the size distribution using a particle size analyzer indicated that approximately 90% of the ceramic debris was smaller than 3.2 µm (2.0 ± 0.4 µm), which is considered clinically relevant. The results for mRNA expression of ALP, OCN, and OPN and alizarin red S staining indicated that cell differentiation and bio-mineralization were significantly inhibited by the presence of ceramic debris at all tested concentrations (P < 0.05, and the values decreased gradually with the increase of ceramic debris concentration), but the results of the CCK-8 assay showed that cell proliferation was not significantly affected (P > 0.05; there was no significant difference between the groups at 1, 3, and 5 days). In addition, the results of ELISA, RT-PCR, and western blotting demonstrated that ceramic debris significantly promoted the release of inflammatory factors, including TNF-α, IL-ß, and IL-6 (P < 0.05, and the values increased gradually with the increase of ceramic debris concentration), and also greatly reduced the mRNA expression of Smad1, Smad4, and Smad5 (the values decreased gradually with the increase of ceramic debris concentration) as well as protein expression of phosphorylated Smad1, Smad4, and Smad5. CONCLUSION: Ceramic debris may affect differentiation and bio-mineralization of MC3T3-E subclone 14 cells through the bone morphogenetic protein/Smad signaling pathway.


Asunto(s)
Cerámica/efectos adversos , Cuerpos Extraños/complicaciones , Prótesis de Cadera/efectos adversos , Osteoblastos/citología , Células 3T3 , Fosfatasa Alcalina/metabolismo , Animales , Artroplastia de Reemplazo de Cadera , Biomarcadores/metabolismo , Western Blotting , Diferenciación Celular , Proliferación Celular , Citocinas/metabolismo , Ratones , Osteocalcina/metabolismo , Osteopontina/metabolismo , Proteínas Smad/metabolismo
17.
BMC Musculoskelet Disord ; 20(1): 385, 2019 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-31438921

RESUMEN

BACKGROUND: Total hip arthroplasty (THA) is used increasingly in younger patients. There is little knowledge about the effect of THA characteristics on risk of revision, especially in young patients. Therefore, we studied the influence of both patient-related and surgical factors on the risk of revision using data from the Dutch Arthroplasty Registry (LROI). METHODS: All patients younger than 55 years with a primary THA implanted in the Netherlands between 2007 and 2017 were selected (n = 19,682). The covariates age, sex, primary diagnosis, ASA-classification, surgical approach, fixation method, bearing type, head size and year of surgery were entered into Cox proportional hazards models to calculate hazard ratios for the risk of revision. RESULTS: The overall 5-year survival of primary THA was 95.3% (95% CI, 94.9-95.6). Use of the anterior approach resulted in a lower risk of revision than the use of the posterolateral approach (HR: 0.66, 95% CI: 0.47-0.92). THAs with a head diameter ≥ 38 mm had a higher risk of revision (HR: 1.90, 95% CI: 1.33-2.72) than THAs with 32 mm heads. Use of MoM bearings resulted in an increased risk when compared to C-PE (HR: 1.76, 95% CI: 1.27-2.43). CONCLUSION: The risk of revision in patients younger than 55 years depends on surgical approach, head size and bearing type. The anterior approach resulted in a decreased risk of revision, whereas use of ≥38 mm heads and MoM bearings resulted in an increased risk of revision for any reason.


Asunto(s)
Artroplastia de Reemplazo de Cadera/efectos adversos , Cabeza Femoral/anatomía & histología , Prótesis de Cadera/efectos adversos , Falla de Prótesis , Reoperación/estadística & datos numéricos , Adulto , Artroplastia de Reemplazo de Cadera/instrumentación , Artroplastia de Reemplazo de Cadera/métodos , Cerámica/efectos adversos , Estudios de Cohortes , Femenino , Cabeza Femoral/diagnóstico por imagen , Cabeza Femoral/cirugía , Humanos , Masculino , Prótesis Articulares de Metal sobre Metal/efectos adversos , Persona de Mediana Edad , Países Bajos/epidemiología , Polietileno/efectos adversos , Diseño de Prótesis , Sistema de Registros/estadística & datos numéricos , Factores de Riesgo
18.
Bone Joint J ; 101-B(8): 897-901, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31362553

RESUMEN

Ceramic bearings have several desirable properties, such as resistance to wear, hardness, and biocompatibility, that favour it as an articulating surface in hip arthroplasty. However, ceramic fracture remains a concern. We have reviewed the contemporary literature, addressing the factors that can influence the incidence of ceramic bearing surface fracture. Cite this article: Bone Joint J 2019;101-B:897-901.


Asunto(s)
Artroplastia de Reemplazo de Cadera/instrumentación , Cerámica , Prótesis de Cadera , Diseño de Prótesis , Falla de Prótesis , Cerámica/efectos adversos , Prótesis de Cadera/efectos adversos , Humanos , Falla de Prótesis/efectos adversos , Falla de Prótesis/etiología
19.
BMC Musculoskelet Disord ; 20(1): 332, 2019 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-31315587

RESUMEN

BACKGROUND: Head breakage is a serious complication following total hip arthroplasty when using Ceramic on Ceramic bearings surfaces. There is still in controversy about the selection of bearing surfaces when conducting revision surgery. CASE PRESENTATION: We describe the case of a fifty-year-old man who had undergone right total hip arthroplasty (THA) with ceramic-on-ceramic prostheses in 2011. After a fall 6 years after the primary procedures, radiographs suggested a ceramic head breakage for revision THA with exchange of metal-on-polyethylene bearing. However, 8 months later, severe metallosis and multiple pseudotumor was confirmed in pelvis and surrounding hip after re-revision THA with ceramic-on-polyethylene prostheses. Analysis of the serum metal ion indicated massive wear of the metal head and erosion of the stem neck and taper. CONCLUSIONS: This case vividly demonstrates metal bearings should be avoided and revision with complete synovectomy and thorough debridement should be performed whenever possible for a fractured ceramic bearing.


Asunto(s)
Artroplastia de Reemplazo de Cadera/efectos adversos , Prótesis de Cadera/efectos adversos , Falla de Prótesis/efectos adversos , Reoperación/efectos adversos , Artroplastia de Reemplazo de Cadera/instrumentación , Cerámica/efectos adversos , Articulación de la Cadera/diagnóstico por imagen , Articulación de la Cadera/patología , Articulación de la Cadera/cirugía , Humanos , Imagen por Resonancia Magnética , Masculino , Metales/efectos adversos , Persona de Mediana Edad , Huesos Pélvicos/diagnóstico por imagen , Huesos Pélvicos/patología , Cintigrafía , Reoperación/instrumentación , Factores de Riesgo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
20.
Eur J Orthop Surg Traumatol ; 29(8): 1623-1629, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31236682

RESUMEN

INTRODUCTION: Spinal surgery of degenerative painful segments is a valuable treatment option in the management of chronic cervical and low back pain. The surgery consists in stabilizing and fusing painful vertebral segment(s). The objective of the study was to report our experience with 45S5 bioactive glass (BAG) to obtain inter-vertebral fusion in the context of posterior spine surgery. MATERIAL AND METHOD: In this retrospective study, 30 patients with a wide range of degenerative and traumatic conditions of the cervical or lumbar spine underwent spinal fusion utilizing a synthetic bone graft substitute of BAG (GlassBone™, Noraker, Lyon-Villeurbanne, France). The pain was evaluated by VAS score, and graft consolidation was assessed on according radiographic images at 1-year post-op. RESULTS: All patients underwent posterior spinal fusion either in the cervical or the thoraco-lumbar spine. Multi-level fusions represented the majority of the cohort (43% of patients with more than seven levels treated). Radiographic imaging demonstrated excellent fusion rates (93%) at final follow-up, equivalent to the outcomes reported in the literature for autogenous bone, with excellent bone bridging and no spinal implant loosening. Only two cases of non-union were encountered. Additionally, 90% of the patients demonstrated recovery at 1 year after surgery with a pain reduction of 60%. CONCLUSION: The results of this retrospective study suggest that the 45S5 BAG may be an interesting alternative option to autologous graft, in terms of safety and bone fusion efficiency. LEVEL OF EVIDENCE: IV Retrospective study.


Asunto(s)
Sustitutos de Huesos/uso terapéutico , Cerámica/uso terapéutico , Dolor de la Región Lumbar/cirugía , Enfermedades de la Columna Vertebral/cirugía , Fusión Vertebral/métodos , Adulto , Anciano , Anciano de 80 o más Años , Sustitutos de Huesos/efectos adversos , Cerámica/efectos adversos , Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/cirugía , Dolor Crónico/cirugía , Femenino , Vidrio , Humanos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Estudios Retrospectivos , Enfermedades de la Columna Vertebral/fisiopatología , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Adulto Joven
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...