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Purpose: Bone repair aims to restore the anatomical, biomechanical, and functional integrity of the affected structure. Here we study the effects of ascorbic acid (AA) and epidermal growth factor (EGF) applied in a single dose and in combination on the repair of a noncritical bone defect model. Methods: Twenty-four rats were divided into four groups: an intact G-1 control group, and three groups that underwent a noncritical bone defect in the right tibia: G-2 treated with AA, G-3 treated with EGF, and G-4 treated with AA in combination with EGF. After 21 days of treatment, rats were sacrificed, the tibias were dissected and a destructive biomechanical analysis of three-point flexion test was performed in a universal testing machine; the values of stiffness, resistance, maximum energy, and energy at maximum load were statistically compared. Results: G-3 and G-4 recovered the biomechanical properties of strength and stiffness of an intact tibia 3 weeks after their application. Not so the energy and energy at maximum load. For G-2, only the stiffness of an intact tibia was recovered. Conclusion: EGF and AA-EGF applied to a noncritical bone defect in the rat tibia favors the recovery of bone resistance and stiffness.

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Purpose: To evaluate the in vivo efficiency of commercial polymeric membranes for guided bone regeneration. Methods: Rat calvarial critical size defects was treated with LuminaCoat (LC), Surgitime PTFE (SP), GenDerm (GD), Pratix (PR), Techgraft (TG) or control (C-) and histomorphometric analysis determined the percentage of new bone, connective tissue and biomaterial at 1 or 3 months. Statistical analysis used ANOVA with Tukey's post-test for means at same experimental time and the paired Student's t test between the two periods, considering p < 0.05. Results: New bone at 1 month was higher for SP, TG and C-, at 3 months there were no differences, and between 1 and 3 months PR had greater increase growthing. Connective tissue at 1 month was higher for C-, at 3 months for PR, TG and C-, and between 1 and 3 months C- had sharp decline. Biomaterial at 1 month was higher for LC, in 3 months for SP and TG, and between 1 and 3 months, LC, GD and TG had more decreasing mean. Conclusion: SP had greater osteopromotive capacity and limitation of connective ingrowth, but did not exhibit degradation. PR and TG had favorable osteopromotion, LC less connective tissue and GD more accelerated biodegradation.

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The use of selective barriers as resorbable membranes has become a routine clinical procedure for guided bone regeneration. Therefore, the production of membranes with a low inflammatory potential during their resorption process has become the goal of a considerable number of researches. Aim: The purpose of the present study was to evaluate the biocompatibility of poly (L- lactic acid) (PLLA) and biocelulose membranes (BC) inserted in the subcutaneous tissue on the dorsum of rats. Methods: Fifteen animals underwent surgical procedures for the insertion of 4 types of membranes: COL (Collagen membrane) ­ Control Group; BC (Biocellulose membrane); BCAg (Biocellulose membrane impregnated with Silver); PLLA (Poly (L-lactic acid) membrane). All membrane types were inserted into each animal. Animals were euthanized after 3, 7, and 15 days of the surgical procedure. Descriptive histological analyses were carried out to investigate host tissue reaction to membrane presence by assessing the anti-inflammatory process composition associated with the membrane resorption and the presence of foreign-body reaction or encapsulation. Results: The BC membranes showed a higher degree of inflammation and poor pattern of integration with the surrounding tissues than the PLLA and COL membranes. Conclusion: The PLLA and COL membranes present better biocompatibility than the BC membranes

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La termografía es eficaz para detectar la temperatura de la superficie corporal y puede utilizarse como método auxiliar para diagnosticar procesos inflamatorios y para evaluar patrones de cicatrización, lo que permite su amplio uso en Medicina Veterinaria. El procedimiento ha ganado protagonismo por ser una técnica no invasiva, indolora, de bajo costo y segura, ya que elimina la necesidad del uso de contrastes, sedación y radiación. El objetivo de este artículo es analizar la eficacia del uso de la termografía en la evaluación de la biocompatibilidad en la reparación del tejido traqueal, así como identificar procesos inflamatorios tras la implantación de la prótesis impresa en nailon con impresión 3D asociada al elastómero termoplástico - PCTPE. Se dividieron quince conejos blancos de Nueva Zelanda (Oryctolagus cuniculus) machos en tres grupos de diferentes períodos de evaluación (siete, 15 y 30 días). Se implantaron prótesis tridimensionales tras la resección completa de tres anillos traqueales. La evaluación de las imágenes termográficas se realizó en el lugar de implantación de la prótesis traqueal justo antes del procedimiento quirúrgico e inmediatamente antes de la eutanasia. Hubo una diferencia significativa entre los grupos, ya los 30 días la temperatura mínima (p = 0,0357), media (p = 0,0135) y máxima (p = 0,0058) fue menor en comparación con los otros grupos...(AU)

Thermography is efficient for detecting body surface temperature and can be used as an auxiliary method for the diagnosis of inflammatory processes and in the evaluation of scarring patterns, which allows its wide use in Veterinary Medicine. The procedure has gained prominence, as it is a non-invasive, painless, low-cost and safe technique, since it does not require the use of contrasts, sedation and radiation. The objective of this article is to analyze the efficiency of the use of thermography in the evaluation of biocompatibility in tracheal tissue repair, as well as to identify inflammatory processes after implantation of the 3D printed impression prosthesis of nylon associated with the thermoplastic elastomer - PCTPE. Fifteen male New Zealand White rabbits (Oryctolagus cuniculus) were divided into three groups of different evaluation periods (seven, 15 and 30 days). Three-dimensional prostheses were implanted after complete resection of three tracheal rings. The evaluation of the thermographic images was performed at the place of implantation of the tracheal prosthesis just before the surgical procedure and immediately before euthanasia. There was a significant difference between the groups, and at 30 days the minimum (p = 0,0357), average (p = 0,0135) and maximum (p = 0,0058) temperature was lower when compared with the other groups...(AU)

A termografia é eficiente para detecção da temperatura da superfície corporal e pode ser utilizada como método auxiliar de diagnóstico de processos inflamatórios e na avaliação de padrões cicatriciais, o que permite sua ampla utilização na Medicina Veterinária. O procedimento tem ganhado destaque, pois trata-se de técnica não invasiva, indolor, de baixo custo e segura, pois dispensa a necessidade do uso de contrastes, sedação e radiação.  O objetivo desse artigo é analisar a eficiência do uso da termografia na avaliação da biocompatibilidade em reparação tecidual traqueal, bem como identificar processos inflamatórios após a implantação da prótese impressa em impressão 3D de náilon associado ao elastômero termoplástico- PCTPE. Quinze coelhos machos, da linhagem Nova Zelândia Branco (Oryctolagus cuniculus), foram distribuídos em três grupos de períodos de avaliação diferentes (sete, 15 e 30 dias). As próteses tridimensionais foram implantadas após ressecção completa de três anéis traqueais. A avaliação das imagens termográficas foi efetuada no local de implantação da prótese traqueal no momento anterior ao procedimento cirúrgico e imediatamente antes da eutanásia. Houve diferença significativa entre os grupos, sendo que aos 30 dias a temperatura mínima (p=0,0357), média (p=0,0135) e máxima (p=0,0058) foi menor quando comparado com os demais grupos...(AU)

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Introducción: El panorama demográfico en el mundo está cambiando. La población mayor de 60 años es el segmento que está creciendo más rápidamente y en el que las enfermedades del tejido óseo se presentan con más frecuencia, lo que aumenta la demanda de materiales y tecnologías apropiadas para restaurar estos tejidos. Objetivo: Analizar la información que se ha generado sobre el desarrollo de biomateriales compuestos para la reparación ósea, con énfasis en la identificación de las tecnologías emergentes basadas en el uso del campo electromagnético, sus aplicaciones y potencialidades. Métodos: Se consultaron trabajos científicos publicados en libros, revistas, patentes y tesis. El 80 por ciento de la documentación seleccionada pertenece al periodo 2010-2019. Análisis e integración de la información: Los métodos identificados fueron clasificados en cinco grupos: electrodeposición química, ya sea por electrólisis, electroforesis o síntesis electroforética in situ; electroporación; electrohilado; control magnético distal y bioestimulación electromagnética de células y tejidos, directamente o por la introducción de dispositivos que convierten la energía electromagnética en energía mecánica. Conclusiones: Estos métodos permiten la conformación de matrices celulares y acelulares compuestas y, además, dispositivos bioestimuladores con control de los parámetros de construcción y acción, de tal manera, que se logran procesos con mayor grado de reproducibilidad y a la medida de los requerimientos específicos para cada paciente(AU)

Introduction: The global demographic panorama is changing. The population aged over 60 years is the fastest growing segment, as well as the one where bone tissue diseases are most common, increasing the demand of appropriate materials and technologies to restore those tissues. Objective: To analyze the information so far generated about the development of composite biomaterials for bone repair, with an emphasis on the identification of emerging technologies based on the use of the electromagnetic field, its applications and potential. Methods: An analysis was performed of scientific papers published in books, journals, patents and theses. Of the documentation selected, 80 percent was from the period 2010-2019. Data analysis and integration: The methods identified were classified into five groups: chemical electrodeposition, be it by in situ electrophoretic synthesis, electrolysis or electrophoresis; electroporation; electrospinning; distal magnetic control and electromagnetic biostimulation of cells and tissues, either directly or incorporating devices which convert electromagnetic energy into mechanical energy. Conclusions: These methods permit the conformation of composite cellular and acellular matrices as well as biostimulator devices controlling construction and action parameters in such a way that the processes obtained display greater reproducibility and are more in keeping with the specific requirements of each patient(AU)

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La termografía es eficaz para detectar la temperatura de la superficie corporal y puede utilizarse como método auxiliar para diagnosticar procesos inflamatorios y para evaluar patrones de cicatrización, lo que permite su amplio uso en Medicina Veterinaria. El procedimiento ha ganado protagonismo por ser una técnica no invasiva, indolora, de bajo costo y segura, ya que elimina la necesidad del uso de contrastes, sedación y radiación. El objetivo de este artículo es analizar la eficacia del uso de la termografía en la evaluación de la biocompatibilidad en la reparación del tejido traqueal, así como identificar procesos inflamatorios tras la implantación de la prótesis impresa en nailon con impresión 3D asociada al elastómero termoplástico - PCTPE. Se dividieron quince conejos blancos de Nueva Zelanda (Oryctolagus cuniculus) machos en tres grupos de diferentes períodos de evaluación (siete, 15 y 30 días). Se implantaron prótesis tridimensionales tras la resección completa de tres anillos traqueales. La evaluación de las imágenes termográficas se realizó en el lugar de implantación de la prótesis traqueal justo antes del procedimiento quirúrgico e inmediatamente antes de la eutanasia. Hubo una diferencia significativa entre los grupos, ya los 30 días la temperatura mínima (p = 0,0357), media (p = 0,0135) y máxima (p = 0,0058) fue menor en comparación con los otros grupos...

Thermography is efficient for detecting body surface temperature and can be used as an auxiliary method for the diagnosis of inflammatory processes and in the evaluation of scarring patterns, which allows its wide use in Veterinary Medicine. The procedure has gained prominence, as it is a non-invasive, painless, low-cost and safe technique, since it does not require the use of contrasts, sedation and radiation. The objective of this article is to analyze the efficiency of the use of thermography in the evaluation of biocompatibility in tracheal tissue repair, as well as to identify inflammatory processes after implantation of the 3D printed impression prosthesis of nylon associated with the thermoplastic elastomer - PCTPE. Fifteen male New Zealand White rabbits (Oryctolagus cuniculus) were divided into three groups of different evaluation periods (seven, 15 and 30 days). Three-dimensional prostheses were implanted after complete resection of three tracheal rings. The evaluation of the thermographic images was performed at the place of implantation of the tracheal prosthesis just before the surgical procedure and immediately before euthanasia. There was a significant difference between the groups, and at 30 days the minimum (p = 0,0357), average (p = 0,0135) and maximum (p = 0,0058) temperature was lower when compared with the other groups...

A termografia é eficiente para detecção da temperatura da superfície corporal e pode ser utilizada como método auxiliar de diagnóstico de processos inflamatórios e na avaliação de padrões cicatriciais, o que permite sua ampla utilização na Medicina Veterinária. O procedimento tem ganhado destaque, pois trata-se de técnica não invasiva, indolor, de baixo custo e segura, pois dispensa a necessidade do uso de contrastes, sedação e radiação.  O objetivo desse artigo é analisar a eficiência do uso da termografia na avaliação da biocompatibilidade em reparação tecidual traqueal, bem como identificar processos inflamatórios após a implantação da prótese impressa em impressão 3D de náilon associado ao elastômero termoplástico- PCTPE. Quinze coelhos machos, da linhagem Nova Zelândia Branco (Oryctolagus cuniculus), foram distribuídos em três grupos de períodos de avaliação diferentes (sete, 15 e 30 dias). As próteses tridimensionais foram implantadas após ressecção completa de três anéis traqueais. A avaliação das imagens termográficas foi efetuada no local de implantação da prótese traqueal no momento anterior ao procedimento cirúrgico e imediatamente antes da eutanásia. Houve diferença significativa entre os grupos, sendo que aos 30 dias a temperatura mínima (p=0,0357), média (p=0,0135) e máxima (p=0,0058) foi menor quando comparado com os demais grupos...

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O objetivo deste trabalho foi avaliar a resistência à fadiga e ciclos até a falha de 3 zircônias odontológicas após envelhecimento hidrotérmico isolado e um novo protocolo alternado. Discos de zircônia "Y"Z T (VITA), INCORIS "T"ZI (Dentsply Sirona) e "K"ATANA UTML (Noritake Kuraray) (N=135) ­ 1ª, 2ª e 3ª gerações, respectivamente ­, foram divididos em 9 grupos (n=15), com 3 tratamentos para cada zircônia: CF ­ Controle, somente com fadiga mecânica; EF ­ Envelhecido em reator hidrotérmico a 134 ºC por 20 h + Fadiga; EFA: 4 passos de envelhecimentos de 5h alternados com fadiga. O teste de fadiga em flexão biaxial foi realizado com configuração de pistão sob 3 esferas, utilizando o método step-stress (carga inicial: 100 Mpa, step: 50 MPa/10.000 ciclos, frequência: 20 Hz). Os dados foram analisados através de teste Kaplan-Meir e Mantel-Cox com α=0,05, além da análise de Weibull. Discos fraturados foram analisados em estereomicroscópio, Microscopia Eletrônica de Varredura (MEV) e Difratômetro de Raios-X (DRX). O envelhecimento isolado com fadiga aumentou a resistência do grupo TEF (810 ± 76 MPa), enquanto diminuiu a do YEF (516 ± 38 MPa), o protocolo alternado aumentou a resistência apenas para a YZ T (730 ± 59 MPa). A KATANA UMTL não apresentou diferenças para ambos os tratamentos. Igualmente, foi a única a não sofrer transformação de fase T-M. O grupo TEF apresentou maior taxa sobrevivência à fadiga (147,000.00 ciclos). A origem de fratura para todos os espécimes deu-se no lado de tração em defeitos pré-existentes. Zircônias de 2ª geração possuem melhor comportamento mecânico e longevidade pós-envelhecimento e fadiga. Embora seja menos resistente, a KATANA UTML não sofreu degradação

This study aimed to evaluate the fatigue strength and cycles for failure of 3 dental zirconias after isolated and a novel hydrothermal and mechanical fatigue cycling aging protocol. "Y"Z T (VITA), INCORIS "T"ZI (Dentsply Sirona) and "K"ATANA UTML (Noritake Kuraray) zirconia discs (N=135), were divided into 9 groups (n=15), according to 3 proposed treatments for each zirconia: CF (control ­ only mechanical fatigue cycling); AF (aging in hydrothermal reactor at 134°C for 20 h + mechanical fatigue cycling ); AFA (Alternating protocol: 4 steps of 5 h of hydrothermal aging intercalated with mechanical fatigue cycling). Mechanical fatigue aging was performed according to the step stress approach through biaxial flexural setup (piston-on-3-balls, initial strength: 100 MPa, step: 50 MPa/ci000, frequency: 20 Hz) until failure. Data were analyzed using KaplanMeier and Mantel-Cox test (α=0.05), in addition to Weibull analysis. Fractured discs were analyzed in stereomicroscope, Scanning Electron Microscopy and XRay Diffraction. Continuous hydrothermal and mechanical fatigue cycling decreased the fatigue strength of YAF group (516 ± 38 MPa), while the alternating protocol increased it (730 ± 59 MPa). KATANA UTML showed no differences for both treatments and did not undergo T-M phase transformation. The TAF group showed the highest fatigue strength (810 ± 76 MPa) and cycles for failure (147,000.00 cycles). The fracture origin for all specimens was on the tensile side in pre-existing defects. INCORIS TZI zirconia have higher fatigue strength after hydrothermal and mechanical fatigue aging. Although less resistant, KATANA UTML did not suffer chemical degradation

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A engenharia de tecidos caracteriza-se como ciência interdisciplinar, a qual vem desenvolvendo biomateriais para a regeneração do tecido ósseo no âmbito das medicinas humana e veterinária. O objetivo desta pesquisa foi avaliar a regeneração óssea obtida da aplicação do hidrogel de quitosana associado ao glicerol fosfato em falha óssea experimentalmente induzida no rádio de coelhos. Foram utilizados 15 coelhos adultos, distribuídos aleatoriamente em dois grupos, representados por cada um dos rádios de cada animal, sendo um grupo tratado com hidrogel de quitosana associado ao glicerol fosfato (grupo biomaterial - GB) e um grupo que não recebeu tratamento com o biomaterial (grupo controle - GC). Os animais foram avaliados radiograficamente, por densitometria óptica e análise histológica, nos períodos 30, 60 e 90 dias pós-operatórios. Houve superioridade estatística na média geral das avaliações radiográficas do GB (2,33±0,48) sobre o GC (1,77±0,06). As médias gerais de avaliação densitométrica do GB foram superiores às do GC, sendo 6,207±1,374 e 5,71±1,512, respectivamente. A avaliação histopatológica do GB foi superior à do GC nos períodos de 30, 60 e 90 dias. Assim, é possível afirmar que o hidrogel de quitosana constitui biomaterial de características desejáveis, promovendo consolidação óssea mais rápida e eficiente, sem causar reações adversas.(AU)

Tissue engineering is an interdisciplinary science that has been developing biomaterials for bone regeneration in medicine and veterinary medicine, following an imminent need. The aim of this study was to evaluate bone regeneration after use of chitosan hydrogel associated with glycerol phosphate in experimentally induced bone gap in the radius of rabbits. Fifteen adult rabbits were randomly distributed in two experimental groups, represented by each radius of every single animal. The animals in the Biomaterial Group (GB) were treated with a glycerol phosphate-associated chitosan hydrogel and in the Control Group (GC) they received no treatment with the biomaterial. The animals were evaluated clinically, radiographically, histologically and by optic densitometry at 30, 60 and 90 days postoperatively. There was statistical superiority in the general average of the radiographic estimates of GB (2.33 ± 0.48) over the CG (1.77 ± 0.06). The general averages of GB densitometric evaluation were higher than the CG, being 6.207 ± 1.374 and 5.71 ± 1.512, respectively. Histopathological evaluation of GB was superior to CG in periods of 30, 60 and 90 days. Chitosan hydrogel constitutes a biomaterial of desired characteristics, promoting faster and more efficient bone repair when compared to GC.(AU)

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Ayurveda oil contains numerous source of biological constituents which plays an important role in reducing the pain relief caused during bone fracture. The aim of the study is to fabricate the polyurethane (PU) scaffold for bone tissue engineering added with ayurveda amla oil using electrospinning technique. Scanning Electron Microscopy (SEM) analysis showed that the fabricated nanocomposites showed reduced fiber diameter (758 ± 185.46 nm) than the pristine PU (890 ± 116.91 nm). Fourier Infrared Analysis (FTIR) revealed the existence of amla oil in the PU matrix by hydrogen bond formation. The contact angle results revealed the decreased wettability (116° ± 1.528) of the prepared nanocomposites compared to the pure PU (100° ± 0.5774). The incorporation of amla oil into the PU matrix improved the surface roughness. Further, the coagulation assay indicated that the addition of amla oil into PU delayed the blood clotting times and exhibited less toxic to red blood cells. Hence, the fabricated nanocomposites showed enhanced physicochemical and better blood compatibility parameters which may serve as a potential candidate for bone tissue engineering.

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Objetivou-se com este trabalho analisar a resistência de placas ósseas de acrílico, confeccionadas com cortadora a laser CO2, quando submetidas às forças que agem sobre o foco de fratura. Foram utilizados 40 fêmures de ovinos (Ovis aries) e confeccionadas 40 placas de acrílico, os quais foram avaliados em grupos: grupo OP - foram avaliados 20 ossos fraturados reduzidos com 20 placas de acrílico; grupo PS - foram avaliadas 20 placas de acrílico; e grupo OS - foram avaliados 20 ossos íntegros e frescos. Todos foram submetidos a ensaios mecânicos de compressão, flexão, torção e tração, em máquina de ensaios universal EMIC® 10000. Os testes eram interrompidos quando havia fratura do corpo de prova. O grupo PS suportou carga de compressão significativamente superior aos demais grupos OP e OS (13.255±290N, 4.932±827N e 8.681±303N, respectivamente). Já em relação à prova de flexão, o grupo OS foi significativamente mais resistente, com média de 2.698±305N, em relação aos grupos OP e PS, que obtiveram 1.315±92N e 1.537±37N, respectivamente. Conclui-se que as placas de acrílico usinadas a laser apresentam resistência mecânica inferior ao fêmur de ovinos, entretanto, devido à resistência exibida nos testes, demonstraram potencial para serem implantadas em ossos com menor demanda de carga.(AU)

The objective of this work was to analyze the resistance of acrylic bone plates, made with CO 2 laser cutter, when subjected to the forces acting on the fracture focus. Forty ovine femurs (Ovis aries) were used and 40 acrylic plates were prepared and evaluated in groups: In the OP Group, 20 fractured bones reduced with 20 acrylic plates were evaluated; in the PS Group, 20 acrylic plates were evaluated; and in the OS Group 20 intact and fresh bones were evaluated. All were submitted to mechanical tests of compression, bending, twisting and traction in an EMIC® 10000 universal testing machine. The tests were interrupted when the body of proof was fractured. The PS group supported a significantly higher compression load than the other OP and OS groups (13,255±290 N, 4,932±827 N and 8,681±303 N, respectively). Regarding the flexural test, the OS group was significantly more resistant, with a mean of 2,698±305 N, compared to the groups OP and PS that obtained 1,315±92 N and 1,537±37 N respectively. It is concluded that the laser-machined acrylic plates have inferior mechanical resistance to the femur of the ovine, however, due to the presented resistance, it shows potential to be implanted in bones with lower load demand.(AU)

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