Clinical Evaluation of Composite Restorations with and without Polyethylene Fiber in First Permanent Molars: A 24-Month Randomized Clinical Trial

ABSTRACT Objective: To evaluate the 24-month clinical performance of composite resin restorations with and without polyethylene fiber in the first permanent molars of pediatric patients with extensive caries. Material and Methods: In total, 75 Class II restorations were placed in the permanent molar teeth of 75 children (mean age 11.3 years) with (FC; n=38) or without (C; n=37) fiber. One operator placed all the restorations. The restorations were evaluated using the modified USPHS criteria in terms of retention, color match, marginal discoloration, anatomic form, marginal adaptation, secondary caries, and postoperative sensitivity. Statistical data were analyzed using chi-square and Cochran tests (p<0.05). Results: At the end of two years, 65 restorations (FC:31; C:34) were followed up. No changes were observed during the first six months. After 24 months of follow-up, there were minor changes in marginal adaptation and marginal color in both groups; however, no statistically significant difference was observed between the clinical performances for all criteria (p>0.05). Conclusion: Extensive composite restorations with or without fibers displayed good clinical performance in high load-bearing areas after 24 months.

Reparación primaria versus reparación y aumentación con cinta de polietileno de alto peso molecular en lesiones del ligamento cruzado anterior: resultados funcionales / Primary repair versus repair and augmentation with high molecular weight polyethylene tape in ACL injuries. Functional results

Introducción: el objetivo del trabajo es evaluar y comparar resultados funcionales en pacientes que fueron sometidos a una reparación primaria del LCA y aquellos en quienes se efectuó reparación asociada con aumentación con cinta de polietileno. Materiales y métodos: se realizó un estudio comparativo en el que se analizaron ochenta y siete pacientes intervenidos quirúrgicamente por lesión proximal del LCA entre 2017 y 2019. El grupo 1, con lesión Sherman I, fue tratado con reparación primaria (cincuenta y seis pacientes). En el grupo 2, con lesiones Sherman II, se efectuó reparación más aumentación (treinta y un pacientes). Se evaluaron el IKDC (Lysholm, Tegner, International Knee Documentation Committee), WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index), y KOOS (Knee Injury and Osteoarthritis Score), preoperatorio y a los seis, doce y veinticuatro meses postoperatorios. Se consideraron significativas aquellas pruebas con p <0.001 (IC 95%). Los análisis estadísticos fueron llevados a cabo en el software estadístico R (R Core Team, 2022).Resultados: el índice de falla fue de 10.4% y 7.6% para los grupos 1 y 2, respectivamente, a los dos años del postoperatorio. Todos los scores mejoraron en el postoperatorio y fue estadísticamente significativa la diferencia con el preoperatorio a los seis y a los veinticuatro meses (p <0.001). El tipo de cirugía no tiene un efecto estadísticamente significativo en los scores clínicos. Conclusión: la reparación en una lesión proximal de LCA (Sherman I o II) es una buena alternativa quirúrgica que permite una mejoría rápida de los scores clínicos, buenos resultados y con bajo índice de complicaciones. Nivel de Evidencia: IV

Introduction: the objective of this study is to compare clinical and functional results in patients who underwent primary ACL repair and primary repair associated with augmentation with polyethylene tape. Materials and methods: eighty-seven patients who underwent surgery for proximal ACL injury between 2017 and 2019 were analyzed. The group 1, with Sherman I injury was treated with primary repair (fifty-six patients). In the group 2, with Sherman II lesions, repair plus augmentation was performed (thirty-one patients). IKDC (Lysholm, Tegner, International Knee Documentation Committee), WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index), and KOOS (Knee Injury and Osteoarthritis Score) were evaluated preoperatively and at six, twelve, and twenty-four months postoperatively. Those tests with p <0.001 (95% CI) were considered significant. Statistical analyzes were carried out in the statistical software R (R Core Team, 2022). Results: the failure rate was 10.4% and 7.6% for groups 1 and 2, respectively, at two years after surgery. All the scores improved in the postoperative period, with significant difference respect to the preoperative period at six and at twenty-four months (p <0.001). Type of surgery does not have a significant effect on clinical scores.Conclusion: repairing a proximal ACL injury (Sherman I or II) is a good surgical alternative, which allows fast improvement of clinical scores, good results and a low rate of complications. Level of Evidence: IV

Effect of sealing on the feed out face of trench silos on the performance of confined calves / [Efeito da vedação na porção inicial de silos trincheiras sobre o desempenho de novilhos confinados]

This study aimed to evaluate the productive performance, dry matter intake, apparent digestibility and ingestive behavior of feedlot calves fed corn silage from the feed out face of trench silos with different types of sealing. The animals were divided into three treatments with four repetitions: Conventional seal - double-sided polyethylene of 110µm thickness; Double-sided seal - double-sided polyethylene of 200µm thickness; and Double seal - composed of double face polyethylene with a thickness of 80µm superimposed on a polyamide translucent vacuum film with a thickness of 20µm. The use of double face sealing provided 12.63% increase in average daily gain and improved food conversion by 0.62 percentage points. The apparent digestibility of the diet with double-face sealing system silage was 4.30% higher than the diet with double-face sealing silage and 11.00% higher than the diet with conventional sealing silage. It is recommended to use the double face sealing with 200µm polyethylene and double face sealing with 80µm thick polyethylene on top of a 20µm thick polyamide translucent vacuum film.(AU)

Objetivou-se avaliar o desempenho produtivo, o consumo de matéria seca, a digestibilidade aparente e o comportamento ingestivo de novilhos confinados, alimentados com silagem de milho da porção inicial de silos do tipo trincheira, conservada sob distintos tipos de vedação. Os animais foram divididos em três tratamentos, com quatro repetições: vedação convencional - polietileno tipo dupla face, com espessura de 110µm; vedação dupla face - polietileno tipo dupla face, com espessura de 200µm; e dupla vedação - polietileno tipo dupla face, com espessura de 80µm sobreposto a um filme vácuo translúcido de poliamida, com espessura de 20µm. O uso da vedação dupla face proporcionou incremento de 12,63% no ganho de peso médio diário e melhorou em 0,62 ponto percentual a conversão alimentar. A digestibilidade aparente da dieta com silagem do sistema de vedação dupla face foi 4,30% superior em relação à dieta com silagem da dupla vedação e 11,00% superior à dieta com silagem da vedação convencional. Recomenda-se a utilização tanto da vedação dupla face com polietileno de 200µm quanto da dupla vedação com polietileno tipo dupla face, com espessura de 80µm, sobreposto a um filme vácuo translúcido de poliamida com espessura de 20µm.(AU)

Contaminación por microplásticos en playas del Pacífico de Guatemala: abundancia y características / Microplastics pollution in Pacific beaches of Guatemala: abundance and characteristics

La contaminación por microplásticos (MPs) de tamaño menor a 5 mm ha tomado relevancia en los últimos años debido a su impacto en los ecosistemas. En Guatemala, se carece de información relacionada con MPs, por lo que este estudio tuvo como objetivo evaluar la abundancia y características de MPs en cuatro playas del Pacífico de Guatemala, Ocós, Tulate, Sipacate y Las Lisas. Se colectaron muestras de arena en mayo y octubre de 2019. Los MPs se aislaron y se clasificaron por forma, y el tipo de polímero se identificó a través de un equipo de espectroscopia infrarroja con transformada de Fourier (ATR-FTIR). La abundancia expresada en MPs/m2 en mayo fue de 25.6, 5.6, 0.8 y 0 MPs/m2 para Tulate, Las Lisas, Ocós y Sipacate; mientras que en octubre fue de 59.6, 23.2, 17.6 y 17.6 MPs/m2 en Tulate, Ocós, Las Lisas y Sipacate. Fragmentos, foam, pellets y láminas fueron las formas predominantes de MPs que se encontraron en las playas. El análisis por ATR-FTIR muestra que los principales polímeros identificados en las playas son polietileno, poliestireno y polipropileno. Los resultados de este estudio indican que las playas del Pacífico de Guatemala están contaminadas por MPs de diferentes tipos de polímeros. Además, estos resultados ofrecen información importante a los responsables de la toma de decisiones sobre la eliminación y el manejo de la basura plástica marina.

Microplastics < 5 mm (MPs) pollution has gained relevance in the last years because of its impact on the ecosystems. In Guatemala, information related to MPS as an environmental stressor is lacking, that is why this study aimed to assess the abundance and characteristics of MPS in four beaches to the Pacific Ocean of Guatemala, Ocós, Tulate, Sipacate, and Las Lisas. Sand samples were collected in May and October 2019. MPs were isolated and classified by shape and the type of polymer was identified by using Attenuated Total Reflec-tion-Fourier Transform Infrared Spectroscopy (ATR-FTIR). The abundance expressed in MPs/m2 in May was 25.6, 5.6, 0.8 and 0 MPs/m2 in Tulate, Las Lisas, Ocós, and Sipacate; whereas in October was 59.6, 23.2, 17.6, and 17.6 M Ps /m2 in Tulate, Las Lisas, Ocós and Sipacate. Fragments, foam, pellets, and film were the predominant shapes found on the beaches. The ATR-FTIR analysis indicates that the main polymers identified in the beaches are polyethylene, polystyrene, and polypropylene. The results of this study indicate that the Pacific Beaches of Guatemala are contaminated by MPs of different types of polymers. These results offer important information to decision makers about disposal and management of marine plastic litter.

Comparative Biomechanical Study of Crosslinked Polyethylene Wear with 36-mm Ceramic Femoral Heads and with 32-mm Metal Femoral Heads / Estudo biomecânico comparativo do desgaste do polietileno reticulado com cabeças femorais cerâmicas de 36 mm e com cabeças metálicas de 32 mm

Abstract Objective This study aims to compare the in vitro wear rate of crosslinked, high molecular weight polyethylene coupled to 36-mm diameter ceramic heads and 32-mm diameter metal heads. Methods Ceramic-on-polyethylene (36 mm) and metal-on-polyethylene (32 mm) tribological pairs were submitted to biomechanical tests in a simulator to determine the wear rate after 15 × 106 cycles. Results A statistically significant difference (p= 0.0005) was detected when comparing the wear rate of assemblies with metallic heads (average wear: 14.12 mg/MC) and ceramic heads (average wear: 7.46 mg/MC). Conclusion The present study demonstrated the lower wear rate in prosthetic assemblies using 36-mm crosslinked ceramic-on-polyethylene tribological pairs compared to 32-mm crosslinked metal-on-polyethylene assemblies. This finding demonstrates the effectiveness of ceramic-on-polyethylene tribological pairs, even with large diameter heads.

Resumo Objetivo: O objetivo do presente estudo foi comparar, in vitro, a taxa de desgaste do polietileno de alto peso molecular reticulado acoplado a cabeças cerâmicas de 36 mm de diâmetro e acoplado a cabeças metálicas de 32 mm de diâmetro. Métodos: Foram realizados ensaios biomecânicos em simulador de desgaste para os pares tribológicos cerâmica-poli (36 mm) e metal-poli (32 mm) a fim de verificar a taxa de desgaste após em 15 × 106 ciclos. Resultados: Na comparação entre as medidas de taxa de desgaste dos conjuntos com cabeças metálicas (média:14,12 mg/MC) e cerâmicas (média:7,46 mg/MC) houve diferença estatitsticamente significativa (p= 0,0005). Conclusão: O presente estudo demonstrou menor taxa de desgaste em conjuntos protéticos que utilizaram o par tribológico cerâmica-polietileno reticulado de 36 mm em comparação aos conjuntos com metal-polietileno reticulado de 32 mm. Tal achado demonstra a eficácia do par tribológico cerâmica-poli, mesmo com a utilização de cabeças de grande diâmetro.

Pares articulares en prótesis primaria de cadera. ¿Existe alguna diferencia? / Bearing surfaces in primary hip arthroplasty. Is there any difference?

Resumen: Introducción: En un reemplazo total de cadera primario (RTC), diferentes materiales son los que se usan para las superficies de apoyo. En nuestro medio, las cabezas de metal o cerámica con polietileno altamente entrecruzado (PA) son los más utilizados. Estas combinaciones tienen buenos resultados, pero no es claro cuál es superior clínicamente. Basados en una revisión sistemática de la literatura y de los registros nacionales de artroplastía, el objetivo de este estudio es determinar si existe alguna diferencia significativa desde el punto de vista clínico. Material y métodos: Realizamos una revisión sistemática de la literatura y de los registros nacionales de artroplastía. Buscamos estudios en los que se compararan los tipos de superficie de contacto: cerámica-polietileno altamente entrecruzado (CP) y metal-polietileno altamente entrecruzado (MP), además de los registros nacionales de artroplastía que describieran, con un seguimiento mínimo de 10 años, la tasa de revisión según el tipo de superficie. El desenlace evaluado fue: tasa de revisión por cualquier causa según el tipo de superficie. Resultados: Dos de quince registros nacionales fueron incluidos: el registro australiano muestra una diferencia en la tasa de revisión a 15 años, comparando CP: 6.3 (IC 5.8, 6.7) contra MP: 5.1 (IC 4.6, 5.7). El registro de Nueva Zelanda no muestra diferencias en la tasa de revisión/100 componentes/año: CP de 0.54 (0.48-0.61) en comparación con MP de 0.61 (0.57-0.66). No encontramos estudios clínicos con los criterios de inclusión que respondan la pregunta de investigación. Conclusión: Los resultados de esta revisión muestran una alta supervivencia cuando se usa polietileno altamente entrecruzado; asimismo, los resultados son similares cuando se utilizan cabezas de cerámica o metálicas.

Abstract: Introduction: In primary hip replacement, different materials are used for bearing surfaces. In our medium metal or ceramic heads with highly crossed-linked polyethylene (PA) are the most used. These combinations have good results, but it is not clear which is clinically superior. The objective of this study is to determine whether there is any clinically significant difference based on a systematic review of the literature and national registries of arthroplasty. Material and methods: We conduct a systematic review of the literature and national registries of arthroplasty and we were looking for studies comparing bearing surfaces: ceramic-highly cross-linked polyethylene (CP) and metal-highly cross-linked polyethylene (MP); describing the revision rate according to the surface type with a minimum 10-year follow-up. The outcome evaluated was: review rate for any cause depending on surface type. Results: Two out of fifteen national registries were included. The Australian registry shows a difference in the 15-year revision rate: CP: 6.3 (IC 5.8, 6.7) vs MP: 5.1 (IC 4.6, 5.7). The New Zealand registry shows no differences in revision rate/100 components/year: CP 0.54 (0.48-0.61) vs MP 0.61 (0.57-0.66). We do not find clinical studies with inclusion criteria that answer the research question. Conclusion: The results of this review show a high survival rate with the use of highly cross-linked polyethylene, the results are similar when using ceramic or metal heads.

Influência das suplementações de ômega-3 e melatonina sobre a resposta tecidual de diferentes cimentos endodônticos / The influence of the supplementation of Omega 3 and melatonin on tissue response of different endodontic sealers

O objetivo deste estudo foi avaliar a influência das suplementações de ômega-3 e melatonina sobre a resposta tecidual de cimentos endodônticos. Foram utilizados 72 ratos Wistar alocados em 3 grupos principais: ratos controle tratados com água (TA), ratos tratados com ômega-3 (TO) e ratos tratados com melatonina (TM). Em cada rato foram implantados 4 tubos de polietileno, sendo 1 tubo vazio para controle, e os demais contendo um dos cimentos endodônticos: Sealapex®, AH Plus® e Endofil®. Os períodos de avaliação foram de 5, 15 e 30 dias (n=8/tempo). Após eutanásia, os tubos foram removidos e processados para análise microscópica. A inflamação foi avaliada em coloração de H.E. e técnica imunohistoquímica para IL-6 e TNF-α, o colágeno pela coloração de Picrosírios red e a deposição de cálcio, pela técnica de von Kossa e luz polarizada. A estatística foi realizada de acordo com cada tipo de análise, com nível de significância de 5% (p <0,05) e considerando cada tipo de suplementação comparado ao controle. Podese observar infiltrado inflamatório reduzido com o tempo e de menor intensidade nos grupos TO ou TM comparado a TA, assim como a imunomarcação para IL-6 e TNF-α. O cimento Sealapex induziu menor inflamação aos 30 dias, tanto em TO quanto em TM. Em relação ao colágeno, foi observado maior expressão de fibras imaturas no grupo TO aos 15 e 30 dias, entretanto, no grupo TM, foi observado maior quantidade de fibras maduras aos 5 dias, ambos comparados a TA. O cimento Sealapex foi único a apresentar marcação positiva para cálcio e cristais de calcita birrefringentes à luz polarizada, independente das suplementações. Pode-se concluir que a suplementação com ômega-3 ou melatonina modularam a inflamação, diminuindo o infiltrado inflamatório e a imunomarcação de IL-6 e TNF- α, estimularam o reparo tecidual e não influenciaram no processo de deposição de cálcio(AU)

The aim of this study was to evaluate the influence of omega-3 and melatonin supplements on the tissue response of endodontic sealers. 72 Wistar rats were allocated in 3 main groups: control rats treated with water (TW), rats treated with omega-3 (TO) and rats treated with melatonin (TM). In each rat, 4 polyethylene tubes were implanted, 1 empty tube for control, and the others containing one of the endodontic sealers: Sealapex®, AH Plus® and Endofil®. The evaluation periods were of 5, 15 and 30 days (n = 8 / time). After euthanasia, the tubes were removed and processed for microscopic analysis. Inflammation was evaluated in H.E. staining and immunohistochemical technique for IL-6 and TNF-α, collagen by Picrosírios red staining and calcium deposition by von Kossa and polarized light technique. Statistics were performed according to each type of analysis, with a significance level of 5% (p <0.05) and considering each type of supplementation compared to the control. It is possible to observe a reduced inflammatory infiltrate over time and less intensity in the TO or TM groups compared to TW, as well as the immunolabeling for IL-6 and TNF-α. Sealapex sealer induced less inflammation at 30 days, both in TO and TM. Regarding collagen, a greater expression of immature fibers was observed in the TO group at 15 and 30 days, however, in the TM group, a greater amount of mature fibers was observed at 5 days, both compared to TW. Sealapex sealer was the only one to present positive marking for calcium and birefringent calcite crystals under polarized light, regardless of supplementation. It can be concluded that supplementation with omega-3 or melatonin modulated the inflammation, reducing the inflammatory infiltrate and the immunolabeling of IL-6 and TNF-α, they stimulated tissue repair and did not influence the calcium deposition process(AU)

Evaluación costo-efectividad de las prótesis con superficie cerámica-polietileno vs. metal-polietileno para reemplazo articular primario de cadera en Colombia / Cost-Effectiveness of Ceramic-Polyethylene Vs Metal-Polyethylene Bearing for Primary Total Hip Replacement in Colombia

Introducción Existe una diferencia estadísticamente significativa del 1.2% en la tasa de revisión a 15 años a favor de cerámica- polietileno altamente entrecruzado (CP), demostrada en el registro nacional de artroplastia australiano. Nuestro objetivo es evaluar la costo-efectividad entre los pares: cerámica-polietileno altamente entrecruzado (CP) y metal- polietileno altamente entrecruzado (MP) para el pagador en Colombia. Materiales y métodos Se construyó un árbol de decisiones TreeAge Pro® comparando CP vs MP desde la perspectiva del Sistema de Salud Colombiano (SSC). Los parámetros se tomaron de la mejor evidencia disponible, para la efectividad se realizó una revisión sistemática de la literatura y para los costos se usaron tarifas del mercado local. Se determinó la relación de costo-efectividad incremental, asumiendo un horizonte temporal de 15 años y aplicando una tasa de descuento del 5% para costos y efectividad. La incertidumbre fue controlada por un análisis de sensibilidad determinístico y probabilístico. Resultados Para el SSC, con un umbral de 1 PIB per cápita por año de vida ganado ajustado por calidad (AVAC), en adultos llevados a RTC el uso de CP no es costo-efectiva, dado que la efectividad es similar (MP:11,32 AVAC vs CP: 11,36 AVAC) y el costo es tres veces mayor (MP $ 861.826 COP vs CP $ 2.298.090 COP). El análisis de sensibilidad determinístico demuestra que la variable más importante en el resultado es el costo de la cerámica. Discusión Para el SSC el uso rutinario de cabezas de cerámica en RTC no es una estrategia costo-efectiva.

Background There is a statistically significant difference of 1.2% in the revision rate in a 15 year follow in favour of the use of ceramic on highly cross-linked polyethylene (CP) recently described in the Australian National Joint Registry. The purpose of this study is to compare the cost-effectiveness of CP implants and metal-on-highly cross-linked polyethylene (MP) implants in patients undergoing total hip replacement (THR). Materials and methods A TreeAge Pro® decision tree was constructed in order to determine cost-effectiveness between two bearing surfaces: CP or MP from the perspective of the Colombian Health Care System (CHCS). The model parameters where taken from the best available evidence. For the effectiveness, a systematic review of the literature was performed, and costs were taken from local market rates. The incremental cost-effectiveness ratio was determined assuming a time horizon of 15 years, and a discount rate of 5% was used for costs and effectiveness. Cost-effectiveness uncertainty was controlled with deterministic and probabilistic sensitivity analysis. Results For the CHCS, with a 1PIB per capita threshold adjusted per QALY in adults undergoing (THR), the use of a CP implant is not cost-effective, given that the effectiveness is similar (11.32 QALY for MP vs 11.36 QALY for CP), and the cost is three times higher (MP $ 861.826 COP vs CP $ 2.298.090 COP). The deterministic sensitivity analysis showed that the most important variable in the results is the ceramic cost. Discussion for the CHCS the routine use of ceramic-highly cross-linked polyethylene bearing surface in a THR is not a cost-effective strategy.

Hip prosthesis biomaterials: a challenge in prevention of biofilm formation / Biomateriais de próteses de quadril: um desafio na prevenção da formação de biofilme

The objective of this study was to identify the scientific evidences regarding biofilm formation prevention on hip prosthesis biomaterials. It's an integrative review that aims to answer the following question: what are the scientific evidences regarding biofilm formation prevention on hip prosthesis biomaterials? The search was performed on PubMed portal and on databases: Web of Science, Embase, Cochrane, CINAHL and LILACS. Primary studies about the topic published online up until November 2017 in English, Spanish and Portuguese are included. Among 16 primary studies, 81.25% were in vitro experimental studies, in which polyethylene showed a higher biofilm formation than metallic biomaterials and polymethylmethacrylate. Among clinical studies, Staphylococcus epidermidis and Staphylococcus aureus were isolated in most of joint prosthesis components. New acylase-containing polyurethane coatings, silver-zirconium carbonitride films, bioactive gentamicin, biodegradable gentamicin-hydroxyapatite, vancomycin, titanium-silicon-carbonoxygen-nitrogen films and cross-linked polyethylene combined with vitamin E and a poly(2-methacryloyloxyethyl phosphorylcholine) layer were developed to prevent biofilm formation. Moreover, cobalt-chromium (Co-Cr) ions inhibited bacterial growth, and cobalt-chromium particles reduced biofilm development. The biomaterials that presented properties against biofilm formation were: bioactive gentamicin, biodegradable gentamicin-hydroxyapatite, vancomycin, acylasecontaining polyurethane, cross-linked polyethylene combined with vitamin E-blended and a poly(2-methacryloyloxyethyl phosphorylcholine) layer, silver-zirconium carbonitride films and titanium-silicon-carbon-oxygen-nitrogen films. Moreover, the Co-Cr particles released from metallic joint prosthesis showed higher antibiofilm activity than Co-Cr ions.

O objetivo deste estudo foi identificar as evidências científicas a respeito da prevenção da formação de biofilme em biomateriais de próteses de quadril. Revisão integrativa da literatura, com vistas a responder a seguinte questão: quais são as evidências científicas a respeito da prevenção da formação de biofilme em biomateriais de próteses de quadril? Realizado no portal PubMed da National Library of Medicine e nas bases: Web of Science, Embase, Cochrane, CINAHL e LILACS. Incluíram-se estudos primários sobre a temática, publicados online até novembro de 2017 em inglês, espanhol e português. Dos 16 estudos primários analisados, 81,25% foram pesquisas experimentais in vitro; polietileno demonstrou maior contagem de unidades formadoras de colônia do que materiais metálicos e polimetilmetacrilato. Dos estudos clínicos, Staphylococcus epidermidis e Staphylococcus aureus foram isolados na maioria dos componentes das próteses articulares. Novos revestimentos constituídos de poliuretano contendo acilase, filmes de prata-carbonitreto de zircônio, gentamicina bioativa, gentamicina-hidroxiapatita biodegradável, vancomicina, filmes de titânio-silício-carbonooxigênio-nitrogênio e polietileno reticulado combinado com vitamina E e uma camada de poli (2-metacriloiloxietil fosforilcolina) foram desenvolvidos para prevenção da formação de biofilme. Além disso, íons de cobalto-cromo (Co-Cr) inibiram o crescimento bacteriano, e houve uma tendência das partículas de cobalto-cromo diminuírem o desenvolvimento de biofilmes. Os biomateriais que apresentaram propriedades que previnem a formação de biofilme foram: gentamicina bioativa, gentamicina-hidroxiapatita biodegradável, vancomicina, poliuretano contendo acilase, polietileno reticulado combinado com vitamina E e uma camada de poli (2-metacriloiloxietil fosforilcolina), filmes de prata-carbonitreto de zircônio e filmes de titânio-silício-carbono-oxigênio-nitrogênio. Além disso, partículas de Co-Cr liberadas das próteses articulares metálicas mostraram maior atividade antibiofilme que íons de Co-Cr.

Preoperative care of Polypoid exposed mucosal template in bladder exstrophy: the role of high-barrier plastic wraps in reducing inflammation and polyp size

ABSTRACT Objective To assess the role of high-barrier plastic wrap in reducing the number and size of polyps, as well as decreasing the inflammation and allergic reactions in exstro- phy cases, and to compare the results with the application of low-barrier wrap. Materials and Methods Eight patients with bladder exstrophy-epispadias complex (BEEC) that had used a low density polyethylene (LDPE) wrap for coverage of the exposed polypoid bladder in preoperative care management were referred. The main complaint of their parents was increase in size and number of polyps. After a period of 2 months using the same wrap and observing the increasing pattern in size of polyps, these patients were recommended to use a high-barrier wrap which is made of polyvinylidene chloride (PVdC), until closure. Patients were monitored for the number and size of polyps before and after the change of barriers. The incidence of para-exstrophy skin infection/inflammation and skin allergy were assessed. Biopsies were taken from the polyps to identify histopathological characteristics of the exposed polyps. Results The high barrier wrap was applied for a mean ± SD duration of 12±2.1 months. Polyps' size and number decreased after 12 months. No allergic reaction was detected in patients after the usage of PVdC; three patients suffered from low-grade skin allergy when LDPE was applied. Also, pre-malignant changes were observed in none of the patients in histopathological examination after the application of PVdC. Conclusion Polyps' size and number and skin allergy may significantly decrease with the use of a high-barrier wrap. Certain PVdC wraps with more integrity and less evaporative permeability may be more "exstrophy-friendly".

Characterization of a hyperthermophilic sulphur-oxidizing biofilm produced by archaea isolated from a hot spring

Background: Sulphur-oxidizing microorganisms are widely used in the biofiltration of total reduced sulphur compounds (odorous and neurotoxic) produced by industries such as the cellulose and petrochemical industries, which include high-temperature process steps. Some hyperthermophilic microorganisms have the capability to oxidize these compounds at high temperatures (N60°C), and archaea of this group, for example, Sulfolobus metallicus, are commonly used in biofiltration technology. Results: In this study, a hyperthermophilic sulphur-oxidizing strain of archaea was isolated from a hot spring (Chillán, Chile) and designated as M1. It was identified as archaea of the genus Sulfolobus (99% homology with S. solfataricus 16S rDNA). Biofilms of this culture grown on polyethylene rings showed an elemental sulphur oxidation rate of 95.15 ± 15.39 mg S l-1 d-1, higher than the rate exhibited by the biofilm of the sulphur-oxidizing archaea S. metallicus (56.8 ± 10.91 mg l-1 d-1). Conclusions: The results suggest that the culture M1 is useful for the biofiltration of total reduced sulphur gases at high temperatures and for other biotechnological applications.

Cementado del polietileno en una prótesis de rodilla osteointegrada. Reporte de caso / Cemented polyethylene insert in a well fixed Total knee replacement. Case report

Resumen: Se presenta el caso de una paciente de 94 años de edad, la cual fue intervenida hace 14 años de reemplazo articular de rodilla derecha por gonartrosis; actualmente con gonalgia y datos de inestabilidad. En las radiografías se aprecian signos de desgaste del polietileno y no se observan datos de aflojamiento en los componentes metálicos. El modelo implantado de polietileno ya no se fabrica en la actualidad y los componentes metálicos de la prótesis no presentan aflojamiento, por lo que se decide el cementado de un inserto de polietileno similar a las características previas para que se adapte al componente tibial. A dos años de evolución la paciente se reporta asintomática, con buena funcionabilidad y sin signos radiológicos de desgaste. Sólo se ha encontrado un caso clínico similar en Madrid con resultados igualmente satisfactorios, por lo que creemos que ésta puede ser una solución a un problema que se presenta cada vez más con mayor frecuencia en la práctica quirúrgica y que originalmente sólo se había descrito en revisiones de prótesis de cadera.

Abstract: We present the case of a 94 years- old patient, which was operated 14 years ago of a right total knee replacement for osteoarthritis, actually she suffers of pain and instability; her X ray shown polyethylene wear without loosening of the metal components. The polyethylene insert is not manufactured anymore so we decided cement a new polyethylene insert on the native tibial baseplate. The two years follow up show us a patient asymptomatic, good function and no radiolucencies on the tibial component. We only found a similar case report in Madrid and we believed that this decision, taken from total hip revisions, will succeed.

PPE tube filled with autologous fat in the repair of peripheral nerve: a new proposal / Tubo PPE relleno con grasa autóloga en la reparación de los nervios periféricos: una nueva propuesta

This study proposes the use of a porous polyethylene (PPE) tube as the conductive element in the regeneration in the sciatic nerve sectioning and evaluates the use of fill with autologous fat. The subject was divided randomly into five groups, 3 control and 2 experimental (PPE tube graft with/ without autologous fat). Each group was selected for functional, histological and morphometric evaluation of the sciatic nerve. Functional analysis of the sciatic nerve occurred through the "footprint" values near -100 refer sectioned sciatic nerve, near 0 (zero) refer to control group. On histological analysis of the experimental groups lots of dense connective tissue replacing nerve tissue was observed. In morphometric analysis the group EGPGf got higher performance in all of variables. The use of PPE has shown promise in nerve regeneration with favorable results when associate with fat as a trophic factor in the regeneration.

Este estudio propone el uso de un tubo de polietileno poroso (PPE) como elemento conductor en la regeneración del nervio ciático seccionado y evaluar el uso de relleno con grasa autóloga. Al azar se formaron cinco grupos, 3 y 2 de control experimental (PPE prótesis tubular con / sin grasa autóloga). Cada grupo fue seleccionado para estudiar la forma funcional, histológica y evaluación morfométrica del nervio ciático. Un análisis funcional del nervio ciático se produjo a través de los valores de "huella", cerca de -100 se refiere al nervio ciático seccionado; cerca de 0 (cero) se refiere al grupo control. En el análisis histológico de los grupos experimentales se observó una gran cantidad de tejido conjuntivo denso que sustituye el tejido nervioso. En el análisis morfométrico, el grupo experimental de injerto de polietileno lleno de grasa (EGPGf) obtuvo un mayor rendimiento en todas las variables. El uso de PPE ha mostrado ser prometedor en la regeneración del nervio, con resultados favorables cuando se asocia con la grasa como un factor trófico en la regeneración.

Effects of plasma on polyethylene fiber surface for prosthodontic application

ABSTRACT Plasma technology has the potential to improve the adherence of fibers to polymeric matrices, and there are prospects for its application in dentistry to reinforce the dental particulate composite. Objectives This study aimed to investigate the effect of oxygen or argon plasma treatment on polyethylene fibers. Material and Methods Connect, Construct, InFibra, and InFibra treated with oxygen or argon plasma were topographically evaluated by scanning electron microscopy (SEM), and chemically by X-ray photoelectron spectroscopy (XPS). For bending analysis, one indirect composite (Signum) was reinforced with polyethylene fiber (Connect, Construct, or InFibra). The InFibra fiber was subjected to three different treatments: (1) single application of silane, (2) oxygen or argon plasma for 1 or 3 min, (3) oxygen or argon plasma and subsequent application of silane. The samples (25x2x2 mm), 6 unreinforced and 60 reinforced with fibers, were subjected to three-point loading tests to obtain their flexural strength and deflection. The results were statistically analyzed with ANOVA and the Bonferroni correction for multiple comparison tests. Results SEM analysis showed that oxygen and argon plasma treatments promote roughness on the polyethylene fiber surface. X-ray photoelectron spectroscopy (XPS) analysis shows that both plasmas were effective in incorporating oxygenated functional groups. Argon or oxygen plasma treatment affected the flexural strength and deflection of a fiber reinforced composite. The application of silane does not promote an increase in the flexural strength of the reinforced composites. Conclusions Oxygen and argon plasma treatments were effective in incorporating oxygenated functional groups and surface roughness. The highest strength values were obtained in the group reinforced with polyethylene fibers treated with oxygen plasma for 3 min.

Effect of Plasma and Fiber Position on Flexural Properties of a Polyethylene Fiber-Reinforced Composite

Abstract: The aim of this study was to evaluate the effect of plasma treatment using argon and oxygen gases, combined with fiber position on flexural properties of a fiber-reinforced composite. Eleven groups were evaluated, a non-reinforced control group and 10 groups reinforced with InFibra, a woven polyethylene fiber, varying according to the plasma treatment and fiber position. The samples were prepared using a stainless steel two-piece matrix. The three point bending test was performed in an EMIC testing machine. Flexural strength (FS) and flexural deflection (FD) were calculated from initial (IF) and final (FF) failure. Data were evaluated statistically using Kruskal-Wallis and Mann-Whitney tests (p<0.05). For IF, in all groups with fibers placed on the base, the FS and FD values were significantly higher than those positioned away from the base. The highest value of FS was obtained in the group treated with O 3 min (296.2 MPa) and the highest value of FD was obtained in the group treated with 1 min (0.109 mm). For FF the FS and FD values obtained for the groups with fibers positioned away from the base were similar or higher than those placed on the base. The highest FS value was obtained in the group treated with 1 min (317.5 MPa) and the highest FD value was obtained in the group treated with O 3 min (0.177 mm). Plasma treatment influenced FS and FD. Fiber position and plasma treatment affected the flexural properties of a fiber-reinforced composite.

Resumo O objetivo deste estudo foi avaliar o efeito do tratamento de plasma, utilizando os gases argônio e oxigênio, associado à posição da fibra, nas propriedades mecânicas de um compósito reforçado por fibra. Onze grupos foram avaliados, um grupo controle, sem reforço, e 10 grupos reforçados com Infibra, variando de acordo com o tratamento de plasma e a posição das fibra. As amostras foram preparadas utilizando uma matriz bipartida de aço inoxidável. O teste de flexão de três pontos foi realizado em uma máquina de ensaios EMIC. A resistência à flexão (FS) e deflexão (FD) foram calculados em relação à falha inicial (IF) e final (FF). Os dados foram avaliados estatisticamente pelos testes de Mann-Whitney e Kruskal-Wallis (p<0,05). Para IF, nas fibras posicionadas na base, os valores de FS e FD foram significativamente maiores do que quando as fibras foram afastadas da base em todos os grupos. O maior valor de FS foi obtido no grupo tratado com O 3 min (296,2 MPa) e o maior valor de FD foi obtido no grupo tratado com O 1 min (0,109 mm). Para FF, os valores de FS e FD para os grupos com fibras afastadas da base foram semelhantes ou superiores aos daqueles com fibras na base. O maior valor de FS foi obtido no grupo tratado com O 1 min (317,5 MPa) e o maior valor de FD foi obtido no grupo tratado com O 3 min (0,177 mm). O tratamento de plasma influenciou o FS e o FD. A posição de fibras, assim como o tratamento de plasma, afetaram as propriedades de flexão de um compósito reforçado com fibra.

EVALUACIÓN DE LA PRODUCCIÓN DE PAPA CRIOLLA Solanum phureja CLON PAISA EN CONTENEDORES DE POLIETILENO DE ALTA DENSIDAD BAJO EL MARCO DE AGRICULTURA URBANA / EVALUATION OF "PAPA CRIOLLA" Solanum phureja "CLONE PAISA" PRODUCTION IN HIGH DENSITY POLYETHYLENE CONTAINERS WITHIN THE FRAMEWROK OF URBAN AGRICULTURE

Con el fin de evaluar la producción de papa criolla Solanum phureja clon Paisa en el contexto urbano, se desarrolló una investigación pionera de tipo descriptiva en la cual se evaluaron las siguientes variables: incidencia de plagas, peso en fresco por contenedor, peso fresco total y peso por clasificación comercial. Se utilizaron contenedores de doble fondo de polietileno de alta densidad y técnicas agroecológicas de producción, de las cuales se destaca la fertilización utilizada con base en tres componentes: materia orgánica, minerales y microorganismos. A partir de los datos obtenidos se calculó media, mediana, moda, desviación estándar y se realizó un análisis de la dispersión por medio de cuartiles para el resumen de la información en cada una de las clasificaciones de la papa. También se analizó el rango intercuartílico y coeficientes de variación para establecer la normalidad en la distribución de los datos. Los resultados mostraron que la producción promedio de S. phureja en los contenedores fue de 528,36 g/planta, que al ser comparados con las medias de producción en Colombia y en el departamento de Cundinamarca, se convierten en una alternativa viable, que contribuye de forma directa con el fortalecimiento de la soberanía y seguridad alimentaria. Esta investigación resalta que la producción agroecológica de papa en contenedores bajo el marco de la agricultura urbana y diseñada desde el punto de vista agroecológico, no solo es una realidad para promover la suficiencia y soberanía y seguridad alimentaria por medio de la producción de alimentos saludables de forma autónoma por la comunidad, sino que además se constituye en una herramienta para los procesos de construcción del espacio urbano con beneficios socioculturales, ambientales y paisajísticos.

In order to evaluate the production of "papa criolla" Solanum phureja, Paisa clone in the urban context, a pioneer descriptive research was carried out in which the following variables were assessed: incidence of pests, fresh weight per container, total fresh weight and weight per trade classification. Fresh weight per container. High density polyethylene and ecological techniques double bottom containers were used in production, in which the fertilizer used was based on three components: organic matter, microorganisms and minerals was emphasized. From the data obtained the mean, median, mode, standard deviation and dispersion analysis were calculated by using quartiles for the summary of the information in each of the potato classifications. The interquartile range and coefficients of variation were also analyzed in order to establish normal data distribution. The results showed that the average production of S. phureja in containers was 528.36 g/plant, that, when compared to the media production in Colombia and in the Department of Cundinamarca, become a viable alternative which directly contributes to the strengthening of food security and sovereignty. This research highlights how agroecologic production of potato, in containers under the framework of urban agriculture and designed from an agroecology point of view, is not only a reality to promote food sufficiency, sovereignty and food security through the production of healthy food by the community in an autonomous way, but also becomes a tool in the construction processes of urban space with sociocultural, environmental and landscape benefits.

Sanitizer resistance of biofilm-forming Salmonellaisolated from meat products / Resistência de Salmonella formadora de biofilme isolada de produtos cárneos a sanitizantes

Este estudo avaliou a capacidade de Salmonella enterica subsp. enterica isolada de produtos cárneos formar biofilme e testou sua resistência a diferentes sanitizantes. Vinte cepas foram avaliadas quanto à capacidade de formar biofilme em placas de microtitulação. As cepas formadoras de biofilme foram testadas em superfícies de polietileno de alta densidade, aço inoxidável e vidro e tiveram a sensibilidade ao hipoclorito de sódio e ao iodo avaliada. Duas cepas de Salmonella Enteritidis isoladas de produtos de frango apresentaram capacidade de formar biofilme nas superfícies testadas. Essas cepas alcançaram maiores populações nas superfícies do que aquelas não formadoras de biofilme, e foram mais difíceis de remover ou reduzir. Devido à ação sanitizante ser menos eficiente sobre bactérias formadoras de biofilme, esses micro-organismos podem persistir no biofilme formado sobre as superfícies de equipamentos e utensílios e ocasionalmente contaminar os alimentos antes da sua expedição, aumentando dessa forma o risco de ocorrência de doenças transmitidas por alimentos.(AU)

Spontaneous dislocation of the polyethylene component following knee revision arthroplasty: case report / Luxação espontânea do polietileno após artroplastia de revisão de joelho: relato de caso

Dislocation of the polyethylene component in knee arthroplasty is a rare complication. The main triggering factor is failure of the locking mechanism, which may result from technical errors of insertion, trauma or even implant failure. Here, a case of dislocation of the polyethylene component from the tibial base, nine years after revision arthroplasty, is reported. It is believed that this is the first such case reported in the Brazilian literature...

A luxação do polietileno em artroplastia do joelho é uma complicação rara. O principal fator desencadeante é a falha no mecanismo de travamento, que pode ser decorrente de erros técnicos na inserção, do trauma ou ainda de falha do implante. Os autores relatam caso de luxação do polietileno a partir da base tibial, nove anos após artroplastia de revisão. Acredita-se que seja o primeiro caso relatado na literatura nacional...

Rat subcutaneous tissue response to calcium silicate containing different arsenic concentrations

Objective: To evaluate the response of rat subcutaneous tissue in implanted polyethylene tubes that were filled with GMTA Angelus and Portland cements containing different arsenic concentrations. Material and Methods: Atomic absorption spectrophotometry was utilized to obtain the values of the arsenic concentration in the materials. Thirty-six rats were divided into 3 groups of 12 animals for each experimental period. Each animal received two implants of polyethylene tubes filled with different test cements and the lateral of the tubes was used as a control group. After 15, 30 and 60 days of implantation, the animals were killed and the specimens were prepared for descriptive and morphometric analysis considering: inflammatory cells, collagen fibers, fibroblasts, blood vessels and other components. The results were analyzed utilizing the Kuskal-Wallis test and the Dunn's Multiple test for comparison (p<0.05). Results: The materials showed, according to atomic absorption spectrophotometry, the following doses of arsenic: GMTA Angelus: 5.01 mg/kg, WPC Irajazinho: 0.69 mg/kg, GPC Minetti: 18.46 mg/kg and GPC Votoran: 10.76 mg/kg. In a 60-day periods, all specimens displayed a neoformation of connective tissue with a structure of fibrocellular aspect (capsule). Control groups and MTA Angelus produced the lower amount of inflammatory reaction and GPC Minetti, the highest reaction. Conclusions: There was no direct relationship between the concentration of arsenic present in the composition of the materials and the intensity of the inflammatory reactions. Higher values, as 18.46 mg/kg of arsenic in the cement, produce characteristics of severe inflammation reaction at the 60-day period. The best results were found in MTA angelus. .

Enxerto com tubo de polietileno poroso preenchido com gordura autóloga no reparo de nervo periférico associado com protocolo de imersão em câmara hiperbárica / Graft with porous polyethylene rod filled with autologous adipocytes in peripheral nerve repair associated with immersion in hyperbaric chamber

Os nervos periféricos são extensões do sistema nervoso central e responsável pela interação das atividades entre as extremidades, em suas funções sensitivas e motoras. São vulneráveis aos mesmos tipos de traumas que afetam outros tecidos: contusão, compressão, esmagamento, estiramento, avulsão e laceração. As lesões de nervos periféricos situam-se entre as mais incapacitantes que acometem indivíduos em idade produtiva, em face dos múltiplos aspectos concernentes às sequelas deste tipo de afecção. Desta forma, a interrupção de continuidade da estrutura do nervo, como no caso da neurotmese, por algum tipo de trauma, resulta na interrupção de transmissão dos impulsos nervosos e na desorganização de suas atividades funcionais. Por meio da utilização da microcirurgia foi possível desenvolver técnicas reparadoras que vão desde simples neurorrafia término-terminal até sofisticados procedimentos cirúrgicos com a utilização de enxertos de nervos, veias e artérias invertidas, tubos sintéticos de materiais variados, tais como silicone e polietileno. Outro aspecto que intriga pesquisadores de todo mundo é a utilização de fatores neurogênicos capazes de acelerar ou melhorar a regeneração de nervos periféricos. A gordura autóloga tem sido continuamente referenciada pela sua abundante oferta, no próprio sitio cirúrgico, apresentando resultados promissores, visto que a adventícia dos vasos é constituída por tecido conjuntivo frouxo, rico em adipócitos. Assim, em um trauma, os neuritos oriundos do coto proximal do nervo lesado, ficam diretamente em contato com esses adipócitos. Seguindo este raciocínio, e com base em trabalhos anteriores onde foi usada veia preenchida com músculo esquelético a fresco como enxerto, decidiu-se testar a possibilidade de crescimento axonal por meio de enxerto com tubo de polietileno preenchido por tecido adiposo autólogo associado a protocolo de imersão em câmara hiperbárica, por meio de um estudo Randomizado Controlado...

The peripheral nerves are extensions of the central nervous system and are responsible for the sensory and motor functions of the limbs. These nerves are vulnerable to the same types of traumas that affect other tissues: contusion, compression, crushing, stretching, avulsion, and laceration. Amongst the most disabling kinds of injuries that affect working-age individuals are those of the peripheral nerves; due to the multifaceted characteristics of the aftereffects of the injury. The break in continuity of the nerve structure due to trauma, as in the case of neurotmesis, results in the disruption of the transmission of nerve impulses and the disorganization of their functions. Through the use of microsurgery, it was possible to develop reconstructive techniques that range from a simple end-to-end neurorrhaphy to sophisticated surgical procedures that utilize nerve grafts, inverted veins and arteries, and synthetic rods of varied materials such as silicone or porous polyethylene. Another aspect that intrigues researchers around the world is the utilization of neurogenic factors capable of accelerating or improving the regeneration of peripheral nerves. Autologous fat has been a constant reference in this field of surgery due to its abundant supply at the surgical site itself. The results are promising, as the adventitia of vessels consists of loose connective tissue rich in adipocytes. Thus in a trauma, the neurites derived from the proximal stump of the damaged nerve are in direct contact with these adipocytes. Following this reasoning, and based on previous studies where veins grafted with fresh skeletal muscle were used, we decided to conduct a randomized controlled study to test the possibility of axonal growth by means of grating with a polyethylene rod filled with autologous adipocytes associated with immersion in a hyperbaric chamber. In an attempt to recover the sciatic nerve, a rod 12 mm in length, with a diameter of 0.25 mm, and with pores...