67 documents found, page 1 of 7
Effect of drill speed on the strain distribution during drilling of bovine and ...
Fernandes, M.G.A.; Fonseca, E.M.M.; Jorge, Renato N.; Manzanares, Cristina; Dias, Maria Isabel RibeiroDrilling is an operation commonly required in orthopaedic surgery for insertion of screws and internal fixation of bone fractures. Induced damage is one of the undesired effects of drilling mainly due to the use of inadequate drilling parameters. During the recent years, scientists have been trying to describe the relationship between drilling parameters and bone injury. However, no studies have examined the le...
Three-dimensional dynamic finite element and experimental models for drilling p...
Fernandes, M.G.A.; Fonseca, E.M.M.; Natal, RenatoThe main goal of this paper is to assess the mechanical damage in solid rigid foam materials with similar mechanical properties to the human bone induced by the cutting parameters. In the present study, a three-dimensional dynamic finite element model was developed to simulate the drilling process in solid rigid foam materials and it was validated with experimental results. Using an explicit dynamic numerical s...
Determination of optimal parameters in drilling composite materials to minimize...
Lopes, A.C.; Fernandes, M.G.A.; Ribeiro, J.E.P.C.; Fonseca, Elza M MThis work aims to determine the best combination of drilling parameters which results in the smaller temperature during the bone drilling procedure. An experimental procedure was adopted with the acquisition of two biomechanical blocks from Sawbones (composite material) with similar properties to the human bone. The goal of this experiment resulted in a drilling process to assess the generated temperature on th...
Strain analysis in the drilling of human and bovine bone
Fernandes, M.G.A.; Fonseca, E.M.M.; Natal, Renato; Manzanares, Cristina; Dias, Maria Isabel RibeiroThe growing importance of boné surgical drilling procedures hás moíivated the development ofassessment methods aimed to preveni boné injiiry. Different studies on the parameters influencing boné drilling have been published. However, most of the results are based only in the analysis of temperatures. There is a lack of information on the mechanical damage on boné, especially about boné tissue swface integrity a...
Stress analysis during drilling of human cadaveric tibiae
Fernandes, M.G.A.; Azevedo, Lucas D.; Fonseca, E.M.M.; Natal, Renato; Manzanares, CristinaSignificant researches exist to estimate and to contrai lhe boné drilling temperatures, hawever no published data exist regarding lhe sïress analysis during the boné drilling, mainly in the case ofhuman bonés. The inherent difficulties to thisprocess and to collect human bonés lead to a lack of information about this subject. The present study investigates the influence ofdrill speed on the stresses generation ...
Assessment of different drill diameter on bone drilling process
Fernandes, M.G.A.; Fonseca, E.M.M.; Natal, RenatoDrilling is a highly demanding machining process due to drill bit geometries complexity and the progressive material failure on the workpiece. When applied to living tissues the process assumes greater attention to ensure a minimally invasive procedure. Implant failure may occur as result of the mechanical conditions created around the hole. Simulation of bone drilling could be used as methodology to optimize t...
Sheet metal forming by numerical simulations: 2D and 3D axisymmetric deformatio...
Mouta, K.; Azevedo, Lucas D.; Fernandes, M.G.A.; Fonseca, E.M.M.The aim ofthis work is conduct numerical simulations to verify the deep drawing process and the shape of the final stamping component of a simple profíle of a sheet metal geometry. To evaluate the design of sheet metal forming, ANSYS program was used. A nonlinear dynamic explicit numerical model was developed using two different models: a 3D quarter aad a 2D axisymmetric fínite element model, due the geometry a...
Thermal analysis in drilling of ex vivo bovine bones
Fernandes, M.G.A.; Fonseca, E.M.M.; Jorge, Renato N.; Vaz, Madalena; Dias, Maria Isabel RibeiroBone drilling is a common procedure in Medicine, mainly in traumatology and orthopedic procedure for fractures fixation and in reconstructive surgery. The success of this surgical procedure is dependent on many factors, namely, on heat generation control during the bone drilling. The main concern in bone drilling is the mechanical and thermal damage of the bone induced by inappropriate parameters such as drill ...
The temperature in the drilling of ex-vivo bovine femurs and human cadaveric ti...
Fernandes, M.G.A.; Azevedo, Lucas D.; Fonseca, E.M.M.; Natal, Renato; Manzanares, CristinaIn an ageing society it’s inevitable that the bone fractures occur with increasing frequency. Usually, the fracture treatment involves bone drilling for screw insertion to fix the fractured parts for immobilization. However, high rotational speeds may cause a high rise in bone temperature. It is generally agreed that temperatures above 55°C for a period longer than 30 seconds are deleterious to the bone tissue ...
Avaliação das deformações em osso sintético durante um processo de furação
Fernandes, M.G.A.; Fonseca, E.M.M.; Natal, RenatoFace ao crescente aumento da população idosa verificado nos últimos anos, a técnica de furação constitui atualmente um dos procedimentos cirúrgicos mais utilizados na medicina. Tratando-se de uma ação indispensável no tratamento de fraturas ósseas, bem como no alojamento de implantes dentários, é essencial a utilização de parâmetros de furação adequados que permitam garantir a ausência do dano ósseo. O desenvol...