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This study presents the structural and static analysis of the new Bioactive Kinetic Screw (BKS) using the finite element method (FEM). The FEM was conducted to predict three-dimensional (3D) simulations according to a cutting torque applied at a constant feed rate. The results were compared using two different materials in the BKS simulation: commercially pure titanium (cp-Ti) and titanium alloy (typically Ti6Al4V). BKS modelling was done in Solidworks ® and the FEM analysis was performed in the ANSYS Workbench 2020 R2 ® software. According to the results, it was observed that the low imposed cutting torque and BKS in cp-Ti material are recommended to obtain a less effective stress in the screw. In addition, the low imposed cutting torque and BKS in Ti6Al4V material are recommended to obtain less equivalent strain and total deformation level in the screw.

The main goal of this paper is to calculate the temperature distribution in four different hot-rolled steel profiles (IPE, HEM, L and UAP), during a thermal and transient process due an accidental fire situation. This work presents the lumped capacitance method, according to the section factors effect, and compares all results with the finite element method, using Ansys® numerical program. The basis of the lumped capacitance method is that temperature of the solid body is uniform at any given time instant during heat transient process. This methodology is compared with the numerical results and allows the calculation of the temperature evolution in steel profiles under fire, like an easy way to follow. The results comparison allows to verify an agreement between the used methodologies. This find enabled to conclude that the lumped capacitance method is accurate and could be easily applied. This method allows to calculate a constant temperature distribution for any profile, at any time instant. It was also intended to understand the relationship between the increase in the cross-section and the temperature difference in the profiles. In the studied profiles ranges with the larger cross-section, a lower temperature field was obtained. As conclusion, members with low section factors will heat up more slowly. info:eu-repo/semantics/publishedVersion

Light timer frame (LTF) walls are made of solid timber elements (studs and tracks) and are usually protected by fire insulation materials (gypsum). This investigation finds the residual load bearing capacity of LTF walls after certain fire rating periods (30, 60, 90 and 120). One LTF structure with 3 studs will be analysed with two different protection levels (one and two gypsum layers). The computational model includes the thermal analysis under standard fire and a sequential mechanical analysis with incremental load applied for each fire rated periods. The orthotropic material behaviour is considered temperature dependent, the mechanical analysis considers large displacement behaviour and the charring effect of wood. The results show that the load bearing capacity decreases with the fire exposure time. A new proposal is presented between the load bearing capacity and the fire rating. info:eu-repo/semantics/publishedVersion

Building regulations require fire rating for partition walls under standard fire exposure. New eco building solutions are becoming popular and, in particular, the light timber framed walls. The fire rating of this building element depends on fire testing. Finite element approximation can be used, when models are validated from previous experimental tests. This investigation presents the validation model from a full-scale assembly, using one gypsum board on each side and several solid timber studs. The charring rate in the wood studs is an important predictor for the fire performance of the wall and as well the temperature of the unexposed surface. This investigation also predicts the temperature field in other key points, such as the points located in interface between the studs and gypsum board, for the onset of charring. Finally, the fire resistance is also considered by means of the simplified method (improved model). This models seems to under predict and over predict the results. There is a good approximation between the numerical model (Hybrid –FEM) and the experimental test used for validation, which allowed for a parametric analysis, testing the variation of the gypsum thickness and the thickness of the cavity. The dimension increase of the wood stud does not provide almost any change on the fire resistance of the assembly (insulation), but provides significant modification on the residual area for load bearing capacity. info:eu-repo/semantics/publishedVersion

The main objective of this work is to present a methodology to design (S-W-S) Steel-Wood- Steel connections in double shear, with internal dowel steel fasteners, in fire conditions. Analytical methodologies according Eurocodes were used to determine the load-carrying capacity of the connections. To analyse the load-carrying capacity, different wood densities and steel dowels diameters will be investigated. The number of dowels is not considerably affected by the wood density of the species. To predict the fire exposure, a thermal and transient numerical analysis was performed to obtain the temperature field results in all studied connections. info:eu-repo/semantics/publishedVersion

As lajes em madeira são elementos estruturais com larga aplicação, em particular, na reabilitação de edifícios, espaços interiores e construção de novas estruturas em edifícios. As propriedades mecânicas, térmicas e acústicas fazem deste material uma solução ideal para lajes de pavimentos e coberturas. No entanto, quando expostas a uma ação de acidente tipo fogo é necessário a avaliação do seu comportamento vulnerável com rigor. info:eu-repo/semantics/publishedVersion

Os sarcomas são tumores heterogéneos que se formam no tecido ósseo, tecido conjuntivo, tecido cartilageneo, tecido muscular, tecido adiposo, nervos periféricos e vasos sanguíneos, geralmente nas extremidades. A cimentação é uma técnica utilizada por exemplo, em procedimentos percutâneos como vertebroplastia, cifoplastia, osteoplastia e sacroplastia. Os cimentos ósseos são biomateriais sintéticos compostos por um polímero (pó) e um componente líquido (monómero). A introdução de cimento ósseo no tecido tem como objetivo tratar ou prevenir fraturas patológicas vertebrais e extraespinhais, aliviar a dor em doentes com osteoporose e metástases, por exemplo. info:eu-repo/semantics/publishedVersion

Bone metastases, which are frequently diagnosed late, translate an advanced tumor stage and have a high impact in patients’ quality of life and survival. After the diagnosis and tumor staging, it is important to characterize the bone tumor lesions with specific attention to identify the size, type (osteolytic, osteoblastic, mix), location, etc. in the involved bone [1]. Tumors can destroy the spongy and cortical bone and extend to soft tissues. info:eu-repo/semantics/publishedVersion

Bone and soft tissue sarcomas are heterogeneous tumors that form from bone tissue, connective tissue, cartilaginous tissue, muscle tissue, adipose tissue, peripheral nerves, and blood vessels, usually at its extremities. Cementoplasty is a technique used for example in percutaneous procedures such as vertebroplasty, kyphoplasty, osteoplasty and sacroplasty [1]. cements are synthetic biomaterials composed of a polymer (powder) and a liquid component (monomer), used very successfully in various medical applications. info:eu-repo/semantics/publishedVersion

Bone tumors grow when cells divide without any control, forming a tissue mass. Bone tumors could be benign or malignant, and primary or metastatic due to systemic cancer cells dissemination. They destroy bone and lead to pathologic fractures. The main objective of this work is to study the thermal effect induced by the bone cement polymerization, in the bone metastatic tumor minimization. To assess the clinical effect, it is important to test this methodology before its application and obtain sustained results. In this work, a numerical model was developed to predict the temperature distribution produced by cement polymerization. Thus, distinct tests were produced for different cement sizes introduced in a cortical and spongy bone tumor, with or without an intramedular nail system. info:eu-repo/semantics/publishedVersion

Bone is the third frequent location for haematogenous dissemination of malignant tumors. Patients with multiple bone metastases are exponentially growing. Bone metastases, which are frequently diagnosed late, are associated to imminent and pathological bone fractures. Metastatic disease translates an advanced tumor stage and it has a high impact in patients’ quality of life and survival. The main objective is to study the thermal effect induced by the bone cement polymerization, in the bone metastatic tumor reduction and to understand the role of such procedure and its biomechanical stabilization. To assess the clinical effect, it is important to test this methodology before its application and obtain sustained results. In this work, a computational model was developed to predict the temperature distribution produced by cement polymerization, and verify the reduction of the metastatic tumor area due the thermal effect. Different simulations produced to evaluate the necrosis effect for two cement amount sizes introduced in a cortical and spongy bone tumor. The same computational models were reproduced introducing an endomedular nail in titanium and a femoral stem in cobalt-chrome material in pathological bone fractures. info:eu-repo/semantics/publishedVersion

O profissional de saúde tem ao seu dispor diferentes ofertas no que diz respeito à prótese do joelho, variando essencialmente a geometria e o material. Neste trabalho, utilizaram-se tomografias computorizadas de pacientes, que permitiram desenvolver modelos ósseos, para posterior inserção da prótese de joelho. Três geometrias de próteses diferentes, inseridas no modelo ósseo, vão possibilitar ter conhecimento da influência do material no desempenho do conjunto. Modelos computacionais 2D e 3D, submetidos à compressão, vão permitir eleger a melhor conjugação entre geometria e material. This research was supported by the Portuguese Foundation of Science and Technology under research project UID/EMS/50022/2013. The authors gratefully acknowledge the generosity of the body donors. info:eu-repo/semantics/publishedVersion

The aim of this work is to present an approach for wood-wood-wood (W-W-W) connections design at high temperatures, using a glued laminated in birch timber GL28h, and steel dowelled connectors. All calculations will be performed to determine the cross-section and the number of fasteners at ambient temperature. The designed connection will be considered protected or unprotected with extra-thickness for high temperatures. All requirements. according standards (Eurocode 5: parts 1-1 and 1-2) were conducted to design the W-W-W connection at high temperatures and evaluate the fire resistance time of the element. info:eu-repo/semantics/publishedVersion

Este trabalho de investigação tem como objetivo a avaliação do estado de tensão gerado durante o processo de furação utilizando materiais sólidos de espumas de poliuretano rígidas com características similares ao osso cortical humano cadavérico. Foi desenvolvido um modelo experimental com recurso à técnica de extensometria e termografia, para obtenção das deformações no material e da temperatura na broca. Em simultâneo, foi desenvolvido um modelo numérico de dinâmica explícita calibrado com os resultados experimentais. Com base no estudo efetuado verificou-se que a diminuição da velocidade de avanço, para uma velocidade de rotação constante durante o processo de furação, provoca o aumento das tensões no material, em regiões próximas da zona de furação. info:eu-repo/semantics/publishedVersion

• A madeira é um material de construção muito utilizado, tanto em Portugal como no Brasil, nomeadamente em pavimentos, paredes e soalhos. • A madeira é um recurso renovável. • A madeira possui excelentes características arquitetônicas, térmicas e acústicas, permitindo a assemblagem fácil de conjuntos. • A madeira quando exposta a ações acidentais, tais como condições de incêndio, apresenta a formação de uma camada de carbono na superfície. • No entanto, esta camada pode atrasar o processo de aquecimento para a secção de núcleo, atuando como um isolante. • O complexo comportamento ao fogo é o alvo de estudo deste trabalho. info:eu-repo/semantics/publishedVersion

Until few years ago, design of sheet metal forming was based on knowledge through work experience and expensive trial and error process. Nowadays the use of numerical simulations in different phases of the sheet metal forming process are performed using finite element analysis (Ranganath et al, 2012). Different codes are available for finite element analysis in metal forming such as Abaqus, Dynaform, Nike 2D, Ansys, etc. Deep drawing is the metalworking process used for stamping flat sheets into cup-shaped forms, where the metal is subjected to different types of deformations (Dieter, 1961). The aim of this work is conduct numerical simulations to verify the deep drawing process and the shape of the final stamping component of a simple profile of a sheet metal geometry. To evaluate the design of sheet metal forming, a nonlinear dynamic explicit numerical model was developed using two models: a 3D quarter and a 2D axisymmetric finite element model, due the geometry and loading conditions symmetry to reduce the computational time processing. The numerical simulations showed the shape deformation occurring after start the process and provided detailed quantitative information about expected weakness of the resulting piece. info:eu-repo/semantics/publishedVersion

A furação do tecido ósseo é uma operação indispensável em diversos procedimentos cirúrgicos ortopédicos. No entanto, existem diversos fatores relacionados com o processo de furação que podem provocar dano no tecido ósseo. Os parâmetros de furação como a velocidade de avanço, velocidade de rotação e geometria da broca devem ser cuidadosamente considerados de forma a obter resultados cirúrgicos satisfatórios. info:eu-repo/semantics/publishedVersion

Drilling 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 the process and parameters in order to reduce the bone damage and ensure ideal drilling conditions. In this research, the effect of drill bit diameter on the generated stresses level during drilling was analysed through numerical simulations and compared with experimental results. An explicit dynamic program was used in the simulations of three dimensional elasto-plastic dynamic finite element models. The numerical models were validated with drilling experiments on polyurethane foam materials with similar properties to the human cortical bone. The results indicated that smaller drill bit diameter leads to a decrease in the stress in foam materials for a constant feed-rate and drill speed. The maximum stress occurred in the drilled zone and surrounding tissues. This research was supported by the Portuguese Foundation of Science and Technology under the research project UID/EMS/50022/2013. The third author acknowledges the funding of Project NORTE-01-0145-FEDER-000022 -SciTech -Science and Technology for Competitive and Sustainable Industries, cofinanced by ProgramaOperacional Regional do Norte (NORTE2020), through Fundo Europeu de Desenvolvimento Regional (FEDER). info:eu-repo/semantics/publishedVersion

Drilling is one of the most common processes involved in machining operations. The usual requirement is the efficient material removal. However, when it comes to the living tissues, drilling assumes greater attention to ensure a minimally invasive procedure. This work describes conventional drilling experiments performed on solid rigid polyurethane foams with similar mechanical properties to the human bone. An extensive experimental study was conducted to evaluate the effects of different drill diameters (4, 5 and 6 mm) on the temperature rise and stresses generation during drilling process. Different experimental tests were performed to assess their repeatability. Results from the experiments suggest that both drilling temperatures and stress level increased with increase in the drill tool diameter. info:eu-repo/semantics/publishedVersion

The wood, as a structural material, continues to grow far beyond traditional applications. Connections are often considered as the critical point of timber structures because their resistance and durability mainly depend on the joining design in structural elements. For imposed thermal loads, it remains important to improve the knowledge of the connection behaviour under fire. info:eu-repo/semantics/publishedVersion

Implant failures and post-operative problems may occur after implant placement as a result of the inappropriate conditions during drilling. The analysis of different materials and drilling parameters is crucial to reduce the bone damage and contribute to the success of this medical interventions. In this research, the effect of drilling parameters on the generated stresses and temperatures in the bone during the process was investigated. info:eu-repo/semantics/publishedVersion

Os fabricantes disponibilizam aos profissionais de saúde uma diversificada oferta no que diz respeito a próteses do joelho, variando essencialmente na geometria e no tipo de material. Neste trabalho, utilizaram-se tomografias computorizadas de pacientes, que permitiram desenvolver modelos geométricos e com densidade óssea aproximada, para posterior inserção de uma prótese de joelho. Modelos computacionais 2D e 3D, submetidos à compressão por uma carga assimétrica, vão permitir eleger a melhor conjugação entre a geometria do osso e os materiais envolvidos, no desempenho da prótese. info:eu-repo/semantics/publishedVersion

A artroplastia total do joelho é uma forma de tratamento muito eficaz na recuperação funcional da articulação do joelho. O comprometimento da capacidade funcional do joelho tem crescido significativamente devido ao aumento da longevidade da população e do aumento da atividade dos indivíduos nesta faixa etária. A artroplastia total do joelho tem vida finita, e fatores como a rotura mecânica dos materiais e o deslocamento da prótese podem comprometer o seu sucesso. Os fabricantes disponibilizam aos profissionais de saúde uma diversificada oferta no que diz respeito a próteses do joelho, variando essencialmente na geometria e no tipo de material. info:eu-repo/semantics/publishedVersion

The main goal of this study is to evaluate the thermal behaviour of wooden cellular slabs exposed to fire conditions, according the standard ISO 843 curve. Different numerical simulations for nonlinear thermal and transient analysis will be obtained, using the finite element method. The importance of this study relies on its contribution to an alternative numerical methodology, which allows to determine the safety and fire resistance levels in wooden cellular slabs, with or without insulation materials. info:eu-repo/semantics/publishedVersion

Bone fracture is a feature of everyday life. Most of the treatments involve bone drilling to fixation of implanted medical devices. Bone loss due to excessive produced heat during drilling may weaken the purchase of surgically placed screws and pins, causing them to loosen postoperatively. Decrease the heat generation has a great demand as it helps in better fixation and healing of bone tissue. This paper presents an experimental model to study the effect of drill speed using human cadaveric tibiae. The results revealed that the temperature rise and the duration of temperature elevation decreased when lower drill speeds are used. This research was supported by the Portuguese Foundation of Science and Technology under research project UID/EMS/50022/2013.The authors gratefully acknowledge the generosity of the body donors. info:eu-repo/semantics/publishedVersion

The 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. info:eu-repo/semantics/publishedVersion

The aim of this work is to present a numerical approach, based on finite element method, to predict the thermal assessment in protected and unprotected cellular wooden slabs, externally exposed to fire, using the standard ISO 843 curve. All numerical calculations will be performed to determine the wood residual cross-section and to determine the fire resistance with the use of insulation materials. info:eu-repo/semantics/publishedVersion

O profissional de saúde tem ao seu dispor diferentes ofertas no que diz respeito à prótese do joelho, variando essencialmente a geometria e o material. Neste trabalho, utilizaram-se tomografias computorizadas de pacientes, que permitiram desenvolver modelos ósseos, para posterior inserção da prótese de joelho. Três geometrias de próteses diferentes, inseridas no modelo ósseo, vão possibilitar ter conhecimento da influência do material no desempenho do conjunto. Modelos computacionais 2D e 3D, submetidos à compressão, vão permitir eleger a melhor conjugação entre geometria e material. info:eu-repo/semantics/publishedVersion

Face 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 desenvolvimento de metodologias que avaliem e auxiliem o sucesso destes procedimentos tornou-se um desafio para a comunidade científica. O presente trabalho tem como objetivo avaliar o campo de deformações geradas no tecido ósseo sob um processo de furação, utilizando um material de osso sintético da Sawbones®. info:eu-repo/semantics/publishedVersion

A necrose óssea induzida durante o processo de furação é um fenómeno frequente que contribui para problemas pós-operatórios. O calor de fricção gerado pelo contato entre a broca e a parede do furo é inevitável. No entanto, a utilização de técnicas avançadas para a obtenção do registo térmico durante a furação óssea é importante para a garantia da qualidade durante a furação. O objetivo deste estudo é apresentar dois métodos experimentais diferentes para analisar as condições de furação que geram as temperaturas mais baixas, evitando a ocorrência da necrose óssea. Foram utilizados ossos de bovino ex-vivo para simular o processo de furação considerando os efeitos do diâmetro da broca, velocidade de rotação e velocidade de avanço. Foram realizados diferentes testes experimentais para avaliar a sua repetibilidade. Os resultados identificaram o diâmetro da broca como o parâmetro mais crítico na indução de temperaturas mais elevadas durante a furação óssea. This research was supported by the Portuguese Foundation of Science and Technology under the research project UID/EMS/50022/2013. The third author acknowledges the funding of Project NORTE-01-0145-FEDER-000022-SciTech -Science and Technology for Competitive and Sustainable Industries, co-financed by Programa Operacional Regional do Norte (NORTE2020), through Fundo Europeu de Desenvolvimento Regional (FEDER). info:eu-repo/semantics/publishedVersion

The wooden cellular slabs are lightweight structures, easy to assemble, and with excellent architectural features, as thermal and acoustic conditions. The wooden cellular slabs with perforations are typical and very common engineering solutions, used in the ceiling or flooring plates to improve the acoustic absorption of compartments, and also have a good insulation and relevant architectonic characteristics. However, the high vulnerability of wooden elements submitted to fire conditions requires the evaluation of its structural behavior with accurately. The main objective of this work is to present a numerical model to assess the fire resistance of wooden cellular slabs with different perforations. Also the thermal behavior of the wooden slabs will be compared considering material insulation inside the cavities

Dental implant is used to replace the natural dental root. The process to fix the dental implant in the maxillary bone needs a previous drilling operation. This machining operation involves the increasing of temperature in the drilled region which can reach values higher than 47°C and for this temperature is possible to occur the osseous necrosis [I]. The main goal of this work is to implement an optimization method to define the optimal drilling parameters that could minimize the drilling temperature. The proposal optimization method is the Taguchi method. This method has been used with success in machining processes optimization of metallic materials [2]. However, the Taguchi method is also used in medical applications, namely in dental medicine [3].

Wood is a natural and traditional building material, as popular today as ever, and presents advantages. Physically, wood is strong and stiff, but compared with other materials like steel is light and flexible. Wood material can absorb sound very effectively and it is a relatively good heat insulator. But dry wood burns quite easily and produces a great deal of heat energy. The main disadvantage is the high level of combustion when exposed to fire, where the point at which it catches fire is from 200–400°C. After fire exposure, is need to determine if the charred wooden structures are safe for future use. Design methods require the use of computer modelling to predict the fire exposure and the capacity of structures to resist those action. Also, large or small scale experimental tests are necessary to calibrate and verify the numerical models. The thermal model is essential for wood structures exposed to fire, because predicts the charring rate as a function of fire exposure. The charring rate calculation of most structural wood elements allows simple calculations, but is more complicated for situations where the fire exposure is non-standard and in wood elements protected with other materials. In this work, the authors present different case studies using numerical models, that will help professionals analysing woods elements and the type of information needed to decide whether the charred structures are adequate or not to use. Different thermal models representing wooden cellular slabs, used in building construction for ceiling or flooring compartments, will be analysed and submitted to different fire scenarios (with the standard fire curve exposure). The same numerical models, considering insulation material inside the wooden cellular slabs, will be tested to compare and determine the fire time resistance and the charring rate calculation.

Este trabalho tem como objetivo avaliar o efeito da temperatura no osso devido ao aquecimento provocado pelo processo de furação. Foram realizadas visitas a duas clínicas para acompanhamento da técnica de implantologia dentária e recolhidas imagens termográficas para a leitura da temperatura gerada na broca após o processo de furação. Na colocação de implantes dentários por exemplo, as variáveis que interferem no processo de furação do osso são: a velocidade, o material, o diâmetro, o comprimento e a geometria da ponta da broca. Com este trabalho pretende-se verificar, experimental e numericamente, as variáveis que interferem no aquecimento da estrutura óssea. Para isso, são utilizados materiais compósitos com características similares ao osso cortical e trabecular. A metodologia apresentada revela-se útil e diferenciadora de outros trabalhos, pois são utilizados materiais com características similares aos materiais in vivo. Os métodos experimentais utilizados em laboratório são baseados nas técnicas de termografia e termopares durante a furação dos diferentes materiais. Paralelamente, são utilizados modelos teóricos numéricos, com o recurso à técnica de elementos finitos, para a discussão de resultados. Após a elaboração do trabalho conclui-se que a temperatura na broca é superior à temperatura no osso e aumenta consoante a estrutura do material, isto é, se o material possuir cavidades na sua estrutura a temperatura na broca não é tão elevada como no material compacto.

Em diferentes áreas da medicina existem processos cirúrgicos que envolvem a furação de tecido ósseo, dependendo o seu sucesso da conjugação de diversos parâmetros. A previsão e o controlo dos parâmetros envolvidos são fundamentais para a redução do dano no tecido ósseo. Este trabalho de investigação tem como objetivo avaliar o estado de tensão gerado durante o processo de furação utilizando materiais sólidos de espumas de poliuretano rígidas com características similares ao osso humano. Durante a furação dos materiais sólidos são utilizados métodos experimentais, baseados na extensometria e na termografia, para análise das deformações e da temperatura na broca. Os parâmetros envolvidos na furação são a velocidade de rotação e a geometria da broca constantes em diferentes testes, sendo variável a velocidade de avanço. Em simultâneo, foi desenvolvido um modelo numérico de formulação explícita, com recurso ao método de elementos finitos, através do programa LS-DYNA. Os resultados permitem obter o campo de tensões nos materiais sólidos em função dos diferentes parâmetros de furação. Para a mesma velocidade de rotação e geometria da broca, a diminuição na velocidade de avanço provoca o aumento do nível de tensão. Em relação à resistência mecânica da espuma de poliuretano rígida utilizada, e para a zona de medição instrumentada, não há registo de dano material. O dano é provocado na zona de furação pela remoção do material.

The 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. This research was supported by the Portuguese Foundation of Science and Technology under the research project UID/EMS/50022/2013. The third author acknowledges the funding of Project NORTE- 01-0145-FEDER-000022 -SciTech -Science and Technology for Competitive and Sustainable Industries, cofinanced by Programa Operacional Regional do Norte (NORTE2020), through Fundo Europeu de Desenvolvimento Regional (FEDER).

In 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 and leads to the irreversible death of cells. Decrease the heat generation has a great demand as it helps in better fixation and healing of bone tissue. info:eu-repo/semantics/publishedVersion