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O objetivo deste estudo é realizar uma revisão sistemática, fazendo uma comparação entre dois tipos de cimentos biocerâmicos, MTA e Biodentine™ no selamento da reparação de perfuração de furca, tanto em dentes decíduos como permanentes, avaliando a sua eficácia. Efetuou-se pesquisa eletrónica na base de dados Pubmed, combinando os termos: perforation repair, dental root perforation, mineral trioxide aggregate, Biodentine, MTA, perforation. A pesquisa identificou 212 artigos, dos quais 12 foram considerados relevantes para este estudo. Materiais à base de silicato de cálcio, como MTA, Biodentine™, podem ser vantajosos como materiais de reparação. A capacidade de selamento desses materiais torna-se importante quando são escolhidos para a reparação de uma grande perfuração de furca. Portanto, é clinicamente relevante avaliar e comparar a capacidade de selamento dos materiais mencionados. Podemos concluir que não há diferença significativa entre o cimento MTA e o Biodentine™ na selagem das perfurações de furca. The aim of this study is to perform a systematic review, making a comparison between two types of bioceramic cements, MTA and Biodentine™ in sealing the repair of perforation perforation in deciduous and permanent teeth, evaluating their effectiveness in this aspect. An electronic search was conducted in the Pubmed database, combining the terms: perforation repair, tooth root perforation, mineral trioxide aggregate, Biodentine, MTA, perforation. The search identified 212 articles, of which 12 were considered relevant for this study. Calcium silicate based materials such as MTA, Biodentine™ may be advantageous as repair materials. The sealing ability of these materials becomes important when they are chosen for the repair of a large drill hole. Therefore, it is clinically relevant to evaluate and compare the sealing ability of the mentioned materials. We can conclude that there is no significant difference between MTA cement and Biodentine™ in sealing the perforation holes.

Introduction : pour une Political Ecology des débits environnementaux Le nouveau « modèle mondial de gestion de l’eau » et ses trois piliers (la Gestion Intégrée des Ressources en Eau, les partenariats public-privé et la marchandisation de l’eau), qui émergent à l’échelle internationale à partir des années 1970, ont fait l’objet d’une importante littérature critique en sciences sociales (Bakker, 2010 ; Goldman, 2007 ; Trottier, 2012). Cependant cette attention portée aux nouveaux paradigmes, ...

En 2019, près de 60 % de la population de l’Afrique subsaharienne n’a pas un accès minimal à l’eau, soit près de 800 millions de personnes. Même dans les pays les plus riches, comme l’a montré la crise de l’eau dans la ville du Cap en 2018, la situation est précaire et marquée par de fortes inégalités. Naturalisation — le manque d’eau serait dû à la sécheresse — et fatalisme — la pénurie serait structurelle en Afrique — dominent les discours. Il y a plus de 25 ans, la conférence internationale sur l’eau et l’environnement de Dublin de 1992, avait proposé un « modèle » mondial de gestion de l’eau, fondé sur la gestion intégrée des ressources en eau, les partenariats public-privé et la marchandisation de la ressource en eau. Mais ces politiques ont prouvé leurs limites en Afrique lorsqu’elles ont été appliquées dans des territoires où les configurations hydro-sociales étaient très différentes de celles des pays du Nord où elles avaient été pensées. Les douze chapitres de ce livre, regroupés autour de trois thèmes (compétitions, conflits et coopérations autour de l’accès et des usages de l’eau ; échelles et modalités de la gestion de l’eau ; justices et injustices) montrent, au contraire, l’émergence de nouvelles conditions diversifiées d’accès à la ressource, qui reposent sur des formes de solidarités anciennes ou émergentes, et qui intègrent les configurations hydro-sociales locales. L’objectif de cet ouvrage est d’explorer, à partir de situations concrètes fondées sur des données empiriques récentes, ces formes nouvelles d’organisation, et de voir dans quelle mesure elles pourraient apporter des solutions alternatives aux nombreux problèmes actuels liées à l’accès inégal à l’eau en Afrique.

At the end of Apartheid, South Africa has been pioneering the recognition of a right to water. This right is now enshrined in the democratic Constitution of the country (1996). South Africa is also perceived as a world leader with one of the most ambitious water Act, granting " water for the environment " (or an " ecological reserve ") alongside a human reserve (minimum water for daily human needs). This kind of environmental flow requirement has been experimented elsewhere too, in France amongst other countries. Yet, comparing environmental flows across countries can prove tricky as environmental flow indicators describe a reality that can differ greatly depending on the socio-historical context. In this paper, we put into perspective, in both countries, the implementation of environmental flows undertaken by water agencies in France and by their equivalent in South Africa, catchment management agencies. Despite enjoying different prerogatives, both organisations share the task of performing functions at the periphery of State regulatory action, which implies most often than not to master a more accommodating governing style. Indeed, in South Africa, if environmental flow requirements were initially determined by hydro-ecology experts commissioned by the department of Water Affairs, soon they were re-conceptualised by water managers who had to operationalise environmental flows when dealing with water allocation demands by different users. Environmental flows thus shifted from a hydro-ecology science towards more socio-hydrology knowledge taking into consideration various economic uses and mitigating ecological requirements with socio-economic goals for each river. It eventually led to a more adaptive management approach applied to environmental flows. In France, and more specifically in the southwest, designing and implementing minimum flows indicators can be understood as a dynamic process of co-production between specific knowledge about -and representation of- rivers on the one hand, and water sharing mechanisms between users on the other hand. Such indicators and the regulatory science that inform them, are instruments deployed by the Adour-Garonne Water Agency for the last 50 years. Their goal is to negotiate water flows that have been significantly framed, temporally and spatially, by electricity producers and by irrigators. These indicators are quite regularly contested within diverse local arenas. This, however, never leads to broadening the debate on the logics and legitimacy of the productive activities such indicators support. It has also often contributed to disarm environmental concerns. Such paradox can be explained because, in both countries, environmental flows not only produce knowledge about rivers but simultaneously they tend to sanction specific allocations of water amongst users-–although in a more concealed and discreet way-. Eventually we reflect on how environmental flow indicators rests on a type of knowledge allowing more space for trade-offs and negotiations among water users.