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1.
Polymers (Basel) ; 15(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36679253

RESUMO

The global orthopedic market is forecasted to reach US$79.5 billion by the end of this decade. Factors driving the increase in this market are population aging, sports injury, road traffic accidents, and overweight, which justify a growing demand for orthopedic implants. Therefore, it is of utmost importance to develop bone implants with superior mechanical and biological properties to face the demand and improve patients' quality of life. Today, metallic implants still hold a dominant position in the global orthopedic implant market, mainly due to their superior mechanical resistance. However, their performance might be jeopardized due to the possible release of metallic debris, leading to cytotoxic effects and inflammatory responses in the body. Poly (ether-ether-ketone) (PEEK) is a biocompatible, high-performance polymer and one of the most prominent candidates to be used in manufacturing bone implants due to its similarity to the mechanical properties of bone. Unfortunately, the bioinert nature of PEEK culminates in its diminished osseointegration. Notwithstanding, PEEK's bioactivity can be improved through surface modification techniques and by the development of bioactive composites. This paper overviews the advantages of using PEEK for manufacturing implants and addresses the most common strategies to improve the bioactivity of PEEK in order to promote enhanced biomechanical performance.

2.
Acta sci. vet. (Online) ; 50: Pub. 1851, Jan. 19, 2022. ilus, graf
Artigo em Inglês | VETINDEX | ID: vti-765215

RESUMO

Background: Orthopedic implants are commonly used for different types of surgical procedures to gain optimal functionand to provide stability to both bones and tendon structures. When inserting these implants, the characteristics of the material are important for surgical success, and the ideal implant must be biocompatible and nonallergenic. However, whenmolding an implant to the bone structure, its resistance can change significantly. Implants can be temporary or permanentin the body, and metal possesses properties that make it acceptable for bone repair. In biomedical implants, 2 types aremost common, commercially pure (CP)-Ti and Ti-6A1-4V. They both provide stable fixation and low risk of loosening.Implants made with the same material and composition can perform differently if the material has been altered by processing techniques for different scenarios. Stress, strain and elastic modulus are the primary metrics used in the description ofimplant materials. They can be calculated based on mechanical tests of specimens with defined geometry, most commonlytensile, bending and torsional tests. In order to better evaluate those changes, we compared the mechanical characteristicsof titanium bone plates, before and after they were molded to the bone, to verify and quantify the loss of stiffness andresistance after molding the plate.Materials, Methods & Results: The study was prospective. Orthopedic implant made of commercially pure titanium (CPTi) were divided into 2 groups, one group without plate molding and the other with plate molding to a dog femora bone.Thirty-six plates of different sizes (5.0, 6.5, 8.0, 9.0, 10.0- and 11.0-mm diameter) were divided into 6 groups containing6 plates of each size and submitted to the 4-point flexion test of resistance, using a piece of dog femur (weights of 5, 10,15, 20 and 25 kg) as the bone in which the...(AU)


Assuntos
Animais , Cães , Titânio/análise , Placas Ósseas/veterinária , Materiais Biocompatíveis , Fraturas do Fêmur/cirurgia , Fraturas do Fêmur/veterinária , Próteses e Implantes/veterinária
3.
Acta sci. vet. (Impr.) ; 50: Pub.1851-2022. ilus, graf
Artigo em Inglês | VETINDEX | ID: biblio-1458526

RESUMO

Background: Orthopedic implants are commonly used for different types of surgical procedures to gain optimal functionand to provide stability to both bones and tendon structures. When inserting these implants, the characteristics of the material are important for surgical success, and the ideal implant must be biocompatible and nonallergenic. However, whenmolding an implant to the bone structure, its resistance can change significantly. Implants can be temporary or permanentin the body, and metal possesses properties that make it acceptable for bone repair. In biomedical implants, 2 types aremost common, commercially pure (CP)-Ti and Ti-6A1-4V. They both provide stable fixation and low risk of loosening.Implants made with the same material and composition can perform differently if the material has been altered by processing techniques for different scenarios. Stress, strain and elastic modulus are the primary metrics used in the description ofimplant materials. They can be calculated based on mechanical tests of specimens with defined geometry, most commonlytensile, bending and torsional tests. In order to better evaluate those changes, we compared the mechanical characteristicsof titanium bone plates, before and after they were molded to the bone, to verify and quantify the loss of stiffness andresistance after molding the plate.Materials, Methods & Results: The study was prospective. Orthopedic implant made of commercially pure titanium (CPTi) were divided into 2 groups, one group without plate molding and the other with plate molding to a dog femora bone.Thirty-six plates of different sizes (5.0, 6.5, 8.0, 9.0, 10.0- and 11.0-mm diameter) were divided into 6 groups containing6 plates of each size and submitted to the 4-point flexion test of resistance, using a piece of dog femur (weights of 5, 10,15, 20 and 25 kg) as the bone in which the...


Assuntos
Animais , Cães , Fraturas do Fêmur/cirurgia , Fraturas do Fêmur/veterinária , Materiais Biocompatíveis , Placas Ósseas/veterinária , Titânio/análise , Próteses e Implantes/veterinária
4.
Biomed Mater Eng ; 25(1): 9-23, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25585977

RESUMO

A clear understanding of the dependence of mechanical properties of bone remains a task not fully achieved. In order to estimate the mechanical properties in bones for implants, pore cross-section area, calcium content, and apparent density were measured in trabecular bone samples for human implants. Samples of fresh and defatted bone tissue, extracted from one year old bovines, were cut in longitudinal and transversal orientation of the trabeculae. Pore cross-section area was measured with an image analyzer. Compression tests were conducted into rectangular prisms. Elastic modulus presents a linear tendency as a function of pore cross-section area, calcium content and apparent density regardless of the trabecular orientation. The best variable to estimate elastic modulus of trabecular bone for implants was pore cross-section area, and affirmations to consider Nukbone process appropriated for marrow extraction in trabecular bone for implantation purposes are proposed, according to bone mechanical properties. Considering stress-strain curves, defatted bone is stiffer than fresh bone. Number of pores against pore cross-section area present an exponential decay, consistent for all the samples. These graphs also are useful to predict elastic properties of trabecular samples of young bovines for implants.


Assuntos
Osso e Ossos/fisiologia , Animais , Medula Óssea/fisiologia , Transplante Ósseo , Cálcio/química , Bovinos , Força Compressiva , Elasticidade , Fraturas Ósseas , Humanos , Porosidade , Software , Estresse Mecânico
5.
Ciênc. rural ; Ciênc. rural (Online);40(9): 1980-1986, set. 2010. ilus
Artigo em Português | LILACS | ID: lil-561271

RESUMO

Este trabalho comparou biomecanicamente o uso de um implante ósseo cortical alógeno preservado em mel para a estabilização de osteotomia transversa de ílio em cães, bem como o uso de hemicerclagem de fio de aço isoladamente frente às forças de flexão. Foram testadas bilateralmente 13 pelves caninas em que um lado foi estabilizado com implante ósseo e o outro com hemicerclagem de fio de aço isoladamente. Os protótipos estabilizados com implante ósseo foram estatisticamente mais resistentes às forças de flexão do que os estabilizados com hemicerclagem de fio de aço usada isoladamente. Os resultados demonstraram que o uso de implante ósseo cortical alógeno é uma alternativa viável para a fixação da osteotomia ilíaca em cães.


This study evaluated the biomechanical use of cortical allografts preserved in honey for the stabilization of transverse osteotomy of ilium in dogs, as well as the use of wire hemicerclage alone against the bending forces. Thirteen canine were tested bilaterally, where one side was stabilized with bone graft and the other with wire hemicerclage alone. The prototypes stabilized with bone graft were statistically more resistant to strength flexion than those wire hemicerclage used alone. The results showed that the use of cortical bone implants is a viable alternative for fixing the iliac osteotomy in dogs.

6.
Ci. Rural ; 40(9)2010.
Artigo em Português | VETINDEX | ID: vti-707036

RESUMO

This study evaluated the biomechanical use of cortical allografts preserved in honey for the stabilization of transverse osteotomy of ilium in dogs, as well as the use of wire hemicerclage alone against the bending forces. Thirteen canine were tested bilaterally, where one side was stabilized with bone graft and the other with wire hemicerclage alone. The prototypes stabilized with bone graft were statistically more resistant to strength flexion than those wire hemicerclage used alone. The results showed that the use of cortical bone implants is a viable alternative for fixing the iliac osteotomy in dogs.


Este trabalho comparou biomecanicamente o uso de um implante ósseo cortical alógeno preservado em mel para a estabilização de osteotomia transversa de ílio em cães, bem como o uso de hemicerclagem de fio de aço isoladamente frente às forças de flexão. Foram testadas bilateralmente 13 pelves caninas em que um lado foi estabilizado com implante ósseo e o outro com hemicerclagem de fio de aço isoladamente. Os protótipos estabilizados com implante ósseo foram estatisticamente mais resistentes às forças de flexão do que os estabilizados com hemicerclagem de fio de aço usada isoladamente. Os resultados demonstraram que o uso de implante ósseo cortical alógeno é uma alternativa viável para a fixação da osteotomia ilíaca em cães.

7.
Ci. Rural ; 40(9)2010.
Artigo em Português | VETINDEX | ID: vti-706777

RESUMO

This study evaluated the biomechanical use of cortical allografts preserved in honey for the stabilization of transverse osteotomy of ilium in dogs, as well as the use of wire hemicerclage alone against the bending forces. Thirteen canine were tested bilaterally, where one side was stabilized with bone graft and the other with wire hemicerclage alone. The prototypes stabilized with bone graft were statistically more resistant to strength flexion than those wire hemicerclage used alone. The results showed that the use of cortical bone implants is a viable alternative for fixing the iliac osteotomy in dogs.


Este trabalho comparou biomecanicamente o uso de um implante ósseo cortical alógeno preservado em mel para a estabilização de osteotomia transversa de ílio em cães, bem como o uso de hemicerclagem de fio de aço isoladamente frente às forças de flexão. Foram testadas bilateralmente 13 pelves caninas em que um lado foi estabilizado com implante ósseo e o outro com hemicerclagem de fio de aço isoladamente. Os protótipos estabilizados com implante ósseo foram estatisticamente mais resistentes às forças de flexão do que os estabilizados com hemicerclagem de fio de aço usada isoladamente. Os resultados demonstraram que o uso de implante ósseo cortical alógeno é uma alternativa viável para a fixação da osteotomia ilíaca em cães.

8.
Artigo em Português | LILACS-Express | VETINDEX | ID: biblio-1478323

RESUMO

This study evaluated the biomechanical use of cortical allografts preserved in honey for the stabilization of transverse osteotomy of ilium in dogs, as well as the use of wire hemicerclage alone against the bending forces. Thirteen canine were tested bilaterally, where one side was stabilized with bone graft and the other with wire hemicerclage alone. The prototypes stabilized with bone graft were statistically more resistant to strength flexion than those wire hemicerclage used alone. The results showed that the use of cortical bone implants is a viable alternative for fixing the iliac osteotomy in dogs.


Este trabalho comparou biomecanicamente o uso de um implante ósseo cortical alógeno preservado em mel para a estabilização de osteotomia transversa de ílio em cães, bem como o uso de hemicerclagem de fio de aço isoladamente frente às forças de flexão. Foram testadas bilateralmente 13 pelves caninas em que um lado foi estabilizado com implante ósseo e o outro com hemicerclagem de fio de aço isoladamente. Os protótipos estabilizados com implante ósseo foram estatisticamente mais resistentes às forças de flexão do que os estabilizados com hemicerclagem de fio de aço usada isoladamente. Os resultados demonstraram que o uso de implante ósseo cortical alógeno é uma alternativa viável para a fixação da osteotomia ilíaca em cães.

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