Browsing by Author "Almeida, Paulo"
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- Currently used systems of dental posts for endodontic treatmentPublication . Machado, Joana; Almeida, Paulo; Fernandes, Sampaio; Marques, Arcelina; Vaz, MárioAn advanced stage of a tooth decay promotes an extremely damaged tooth that needs endodontic treatment to be restored. When satisfactory coronal tooth structure remains, an artificial crown can be placed without a post. On the other hand, the treatment of seriously damaged teeth often require an endodontic post. The main reason for using post is to enable rebuilding of the tooth structure prior to crown restoration. Dentists believe that endodontic posts provide a stable and solid restoration of the tooth, as well as providing strengthening of the tooth root, which constitutes the solid basis for a dental crown restoration. However, some authors reported that the strength of the tooth is directly related to the remaining dentin, and because of that, an endodontic treatment can present a higher risk of biomechanical failure. A number of different materials have been used for the manufacturing of dental posts. The fundamental posts requirements include high tensile strength, high fatigue resistance to occlusal and shear loading and a good distribution of the forces affecting the tooth root. The purpose of this article is to review the current literature and identify the various characteristics of a dental post, as well as some principles on the endodontic treatment for tooth decay.
- Currently used systems of dental posts for endodontic treatmentPublication . Machado, Joana; Almeida, Paulo; Fernandes, Sampaio; Marques, Maria Arcelina; Vaz, MárioAn advanced stage of a tooth decay promotes an extremely damaged tooth that needs endodontic treatment to be restored. When satisfactory coronal tooth structure remains, an artificial crown can be placed without a post. On the other hand, the treatment of seriously damaged teeth often require an endodontic post. The main reason for using post is to enable rebuilding of the tooth structure prior to crown restoration. Dentists believe that endodontic posts provide a stable and solid restoration of the tooth, as well as providing strengthening of the tooth root, which constitutes the solid basis for a dental crown restoration. However, some authors reported that the strength of the tooth is directly related to the remaining dentin, and because of that, an endodontic treatment can present a higher risk of biomechanical failure. A number of different materials have been used for the manufacturing of dental posts. The fundamental posts requirements include high tensile strength, high fatigue resistance to occlusal and shear loading and a good distribution of the forces affecting the tooth root. The purpose of this article is to review the current literature and identify the various characteristics of a dental post, as well as some principles on the endodontic treatment for tooth decay.
- Halal tourism market in the city of PortoPublication . Liberato, Pedro; Almeida, Paulo; Liberato, DáliaTendencialmente, os turistas halal procuram destinos turísticos onde existe uma predominância religiosa muçulmana. Contudo, em anos transatos, têm desenvolvido curiosidade em relação a regiões com diferentes estruturas culturais. Além de ser um mercado com uma grande expressividade populacional, é também um dos que mais assegura a circulação de capital. Um dos grandes beneficiários deste movimento tem sido o continente europeu, cuja taxa de visitas de turistas muçulmanos tem observado um aumento gradual. Portugal poderá estabelecer-se como um destino interessante para o turista halal, pois partilha de um legado cultural deixado pelo povo muçulmano durante a sua ocupação da Península Ibérica. O presente estudo tem como objetivo compreender se a cidade do Porto reúne as condições necessárias para acolher o turista halal. Nessa perspetiva, foram listados um conjunto de serviços e produtos, especialmente relacionados com a alimentação e alojamento, que servem não só a população muçulmana viajante, mas também a população muçulmana local. Pretende-se, ainda, averiguar se os stakeholders associados ao setor do turismo têm a consciência dos conceitos “halal” e “turismo halal”, avaliando o interesse da cidade em relação ao segmento estudado. Serão enumeradas as limitações e obstáculos que um viajante muçulmano poderá sentir ao visitar a cidade do Porto. Por forma a assegurar a avaliação dos objetivos propostos, optou-se por uma metodologia qualitativa, utilizando como instrumento de recolha de dados a entrevista semiestruturada. Foram aplicadas dez entrevistas a representantes da comunidade muçulmana local, gestores de unidades hoteleiras, proprietários de restaurantes e ainda agentes de entidades públicas locais. Apesar de existirem serviços e produtos que satisfazem minimamente os requisitos do turista halal, presentemente a cidade do Porto não reúne as condições necessárias para acolher um súbito incremento de procura turística associada à população muçulmana. Torna-se evidente que não há diversidade de oferta ao nível de restaurantes fornecedores de alternativas lícitas de carne. Acresce a inviabilidade para que as unidades hoteleiras apresentem um roteiro de serviços que satisfaça totalmente um cliente islâmico. Se por um lado a falta de procura do cliente muçulmano não motiva financiamento público ou privado aplicado ao segmento halal, por outro, existe a consciência generalizada que a exploração do mercado seria benéfica para a cidade, quer em termos de procura turística, quer ao nível da comunidade local. É visível a postura reativa das Destination Management Organizations (DMOS) regional e local, no Porto, assumindo uma posição dependente das motivações e interesses do turista halal.
- Influence of an innovative dental post approach in dentin mechanical behaviorPublication . Lopes, Carla; Machado, Joana; Almeida, Paulo; Fernandes, Sampaio; Marques, Maria Arcelina; Vaz, MárioThe restoration of seriously damaged teeth often requires an endodontic post. A number of different materials and shapes of dental posts have been manufactured, which leads to different mechanical behaviors. The currently used post systems frequently result in failure or fracture of the tooth, due to the difference between tooth and dentin mechanical properties. Recently, a bundle of fine individual posts made of reinforced fiberglass has been developed. This new approach is not a single-post and it can be spread apart, being individually distributed in the tooth canal. With this configuration, the fine posts can adapt to suit into any root canal anatomy. Biomechanical properties similar to the dentin are being reported as an advantage for the use of this new dental post. The purpose of this study is to understand if the bundle post introduces an improvement in the results of endodontic treatment, compared with the currently used post systems. This study was carried out using the finite element method to determine the influence of stress distribution on dentin, when these two different approaches are used. The results show that stresses at the dentin changed with the dental post used. The use of bundle post appears to better accommodate the developed stress, reducing the stresses in the tooth.
- Population structure of the brazilian carapeba eugerres brasilianus in a complex of lagoon systems from southwest atlantic ocean Inferred from otolith elemental and shape signatures †Publication . Almeida, Paulo; Costa, Marcus; Oliveira, Raiane; Pinto, Edgar; Almeida, Agostinho; Azevedo, Rui; Monteiro-Neto, Cassiano; Correia, Alberto TeodoricoThe Brazilian mojarra, Eugerres brasilianus, is an economically important species for the artisanal fisheries that exist in the estuarine environments along the Southwest Atlantic Ocean. Despite this, knowledge about its population structure is scarce, and no management strategies have been applied to ensure the sustainability of E. brasilianus fisheries in Brazil. Thus, the present study intended to understand the population structure of E. brasilianus in a complex system of lagoons in the Southwest Atlantic Ocean. A total of 90 individuals were collected in the lagoons of Piratininga-Itaipu (IP), Saquarema (SQ) and Araruama (AR) between December 2019 and March 2020. For the analyses, 30 individuals per location from the same age group (2 years old), following age estimation by counting the annual growth increments, were used. The contour of the shape of each otolith was evaluated using elliptical Fourier descriptors (EFD). Multi-elemental signatures (MES) of the whole otoliths were obtained using solution-based inductively coupled plasma mass spectrometry. Data were analyzed using univariate and multivariate statistics to assess the degree of separation between individuals from different lagoons. EFD data showed differences between regions. MES exhibited distinct regional patterns, mainly driven by differences in Sr/Ca, Mg/Ca, Mn/Ca, Li/Ca and Cu/Ca ratios. Reclassification accuracy rates obtained from linear discriminant function analyses using both EFD and MES of otoliths were 100% (IP), 90% (SQ) and 97% (AR). Therefore, a clear distinction between the population groups was observed, probably related to the inherent characteristics of each lagoon system, their semi-restricted connectivity with the adjacent coastal zone, as well as the estuarine-opportunistic behavior of the species. Thus, the results suggest that these fisheries should be managed as different population-units.