Browsing by Author "Dias, Maria Isabel Ribeiro"
Now showing 1 - 10 of 17
Results Per Page
Sort Options
- Composite materials and bovine cortical bone drilling: thermal experimental analysisPublication . Fernandes, Maria; Fonseca, E.M.M.; Natal, Renato; Vaz, M.A.P.; Dias, Maria Isabel RibeiroThe boné drilling is a common procedure in orthopaedic surgery, mainly in the treatment of fractures and reconstmctive surgery. The success of this surgeries is dependent of many factors and also in heat generation control during the drilling boné. The main concem in boné drilling are the mechanical and thermal damage of the boné induced by inappropriate parameters such as drill speed and feed-rate during surgical procedures. This paper studies the problem ofgeneration heat in drilling process ofcomposite materiais, with similar mechanical properties to the human boné, and in bovine cortical boné. The main goal was study the evolution of temperature through the different experimental methodologies using different drilling parameters. It was concluded when the drill speed and feed-rate are higher the boné temperature increase is lower. The results of temperature in the drilling process of composite material or bovine boné were compared and were found a good agreement with both.
- Composite materials and bovine cortical bone drilling: thermal experimental analysisPublication . Fernandes, Maria; Fonseca, E.M.M.; Natal, Renato; Vaz, M.A.P.; Dias, Maria Isabel RibeiroThe bone drilling is common in orthopaedic surgery. The success of this surgery is dependent on many factors, namely on the heat generation control during the bone drilling. The main concern in bone drilling is the mechanical and thermal damage induced by inappropriate parameters, as drill speed and feed-rate.
- Composite materials and bovine cortical bone drilling: thermal experimental analysisPublication . Fernandes, Maria; Fonseca, E.M.M.; Natal, Renato; Vaz, M.A.P.; Dias, Maria Isabel RibeiroThe bone drilling is a common procedure in orthopaedic surgery, mainly in the treatment of fractures and reconstructive surgery. The success of this surgeries is dependent of many factors and also in heat generation control during the drilling bone. The main concern in bone drilling are the mechanical and thermal damage of the bone induced by inappropriate parameters such as drill speed and feed-rate during surgical procedures. This paper studies the problem of generation heat in drilling process of composite materials, with similar mechanical properties to the human bone, and in bovine cortical bone. The main goal was study the evolution of temperature through the different experimental methodologies using different drilling parameters. It was concluded when the drill speed and feed-rate are higher the bone temperature increase is lower. The results of temperature in the drilling process of composite material or bovine bone were compared and were found a good agreement with both.
- Effect of drill speed on the strain distribution during drilling of bovine and human bonesPublication . 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 level of strain generated in the bone during the drilling process. This paper focuses on the analysis of different drill speeds during drilling of fresh bovine femora and human cadaveric tibiae. The main contribution of this work is to determine how differences in applied drill speeds affect the strain of cortical tissue near the drilling site and the drill bit temperature.
- Experimental study of temperatures during drilling of ex-vivo bovine bonesPublication . Fernandes, M.G.A.; Fonseca, E.M.M.; Natal, Renato; Dias, Maria Isabel Ribeiro; Lopes, Ana Catarina Oliveira; Ribeiro, J.E.he thermal bone necrosis induced during a drilling process is a frequent and potential phenomenon, which contributes to post-operative problems. The frictional heat generated from the contact between the drill bit and the hole wall is unavoidable. However, understanding advanced techniques for acquiring reliable thermal data on bone drilling is important to ensure the quality of the drilled hole.
- Ribeiro, J.E.Publication . Fernandes, M.G.A.; Fonseca, E.M.M.; Natal, Renato; Dias, Maria Isabel Ribeiro; Lopes, Ana Catarina OliveiraThe thermal bone necrosis induced during a drilling process is a frequent and potential phenomenon, which contributes to post-operative problems. The frictional heat generated from the contact between the drill bit and the hole wall is unavoidable. However, understanding advanced techniques for acquiring reliable thermal data on bone drilling is important to ensure the quality of the drilled hole. The purpose of this study is to present two different experimental methods to analyse the drilling conditions that generate the lower temperatures, avoiding the occurrence of thermal bone necrosis. Ex-vivo bovine bones were used to simulate the drilling process considering the effect of drill bit diameter, drill speed and feed-rate. Different experiments were performed to assess the repeatability of the tests. The results identified the drill bit diameter as the most critical parameter for inducing higher temperatures in bone drilling.
- Strain analysis in the drilling of human and bovine bonePublication . 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 and the strain distribution during drilling. The challenge diiring drilling should not be Umited to avoid thermal damage but also to predict the strains qffècting the boné, since the cutting force and lhe accuracy of the osíeotomy depends upon the sin-geon 's manual skills.
- Temperature assessment in the drilling of composite materials and ex-vivo porcine bonesPublication . Fernandes, Maria; Fonseca, E.M.M.; Natal, Renato; Dias, Maria Isabel RibeiroThe bone cutting is a procedure widely used in medicine, including orthopaedic, dental and neuro surgeries. The success of this surgeries is dependent of many factors and also in temperature generation during the drilling bone. When an excessive heat is produced during the drilling bone the thermal necrosis can occur, and the bone suffers injuries.(...)
- Temperature assessment in the drilling of composite materials and ex-vivo porcine bonesPublication . Fernandes, Maria Goreti Antunes; Fonseca, E.M.M.; Natal, Renato; Dias, Maria Isabel RibeiroThis study presents different experimental methodologies for analysis and temperature evaluation during the drilling process of composite materials and ex-vivo porcine bones. In the experimental methodologies were evaluated the influence of different parameters on the bone temperature rise. The combinations of different parameters produced temperatures far below the critical values. It was concluded that drill temperature decreases when the feed-rate is higher and, independently, increases with the increasing of hole depth. The influence of drill speed is not clear. In the composite materials the temperature decreases in the drill bit when the drill speed is higher, and in ex-vivo porcine bones happens the opposite. The animal models recorded lower temperature values than composite materials.
- Temperature assessment in the drilling of ex vivo bovine and porcine cortical bone tissuePublication . Fernandes, M.G.A.; Fonseca, E.M.M.; Natal, Renato; Dias, Maria Isabel RibeiroThermal damage in boné tissue is a common problem in drilling processes. The main goal of this work is to analyze the cutting conditions that generate the lower temperature, avoiding the occurrence of thermal boné necrosis. In this work, the effects of the drill speed and the feedrate were studied during the drilling ofcortical bovine and porcine boné tissue. !n the ex vivo drilling operations, two methodologies were performed on several fresh femur boné samples. The present study showed that the combinations of cutting conditions in the drilling process of ex 1//Vo cortiça! bovine and porcine boné tissue, produced temperatures far below the criticai values. It was concluded that the temperature increases with an increasing drill speed and decreases with high feed-rates. To the drill speed, the difference is less clear than that the the feed-rate. The drilling temperatures on the bovine samples were higher than porcine samples.