Erosão dentária associada a distúrbios alimentares

Os distúrbios alimentares traduzem-se em comportamentos, quer pela falta, quer pelo excesso da ingestão de alimentos, sendo a anorexia nervosa e a bulimia as que mais frequentemente se verificam na população. O crescente aumento destes distúrbios, nomeadamente a obsessão pelos corpos magros, está relacionada com o impacto que os media têm na sociedade, uma vez que a magreza é vista como mecanismo de atracção sexual e de integração social. O diagnóstico das desordens alimentares não é fácil de ser efectuado, dado que os sinais são muitas vezes omitidos/ocultados pelos indivíduos. Os médicos dentistas podem ter um papel importante na sua detecção, dadas as manifestações precoces das alterações alimentares na cavidade oral. Há diversos sintomas comuns aos dois distúrbios alimentares como a erosão dentária, a hipersensibilidade dentinária, a hipertrofia das glândulas salivares e consequente hipossalivação, a cárie dentária, a doença periodontal, as mucosites, a candidíase oral e a queilite angular. Resultante do vómito induzido, há o aporte de ácido proveniente do conteúdo gástrico que induz alterações estruturais do esmalte e dentina, facilitando o processo de desgaste erosivo. Os fenómenos erosivos são uma das manifestações orais mais evidentes dos distúrbios alimentares. O conhecimento dos sinais, sintomas e da forma de evolução da erosão dentária, é imprescindível, e acaba por diferenciar a atuação profissional que possibilita um diagnóstico eficaz e o tratamento correto. A elaboração desta dissertação tem como objectivo reforçar a informação sobre estes fenómenos para que possam ser mais eficazmente prevenidos, diagnosticados e controlados/tratados. Para tal efectuou-se uma pesquisa na B-On, Medline/PubMed, sciELO, RCAAP e em livros, de informação válida sobre o tema. Interpôs-se limitação temporal e usaram-se as seguintes palavras-chave na seleção de artigos: “Dental erosion”, “Erosive wear”, “Anorexia”, “Bulimia”, “Eating disorders”.

A national coastal erosion risk assessment for Scotland

The geography of Scotland, with a highly undulating hinterland, long and indented coastline, together with a large number of islands, means that much social and economic activity is largely located at the coast. The importance of the coast is further highlighted by the large number of ecosystem services derived from the coast. The threat posed by climate change, particularly current and future sea level rise, is of considerable concern and the associated coastal erosion and coastal flooding has the potential to have a substantial effect on the socioeconomic activity of the whole country. Currently, the knowledge base of coastal erosion is poor, which serves to hinder the current and future management of the coast. This research reported here aimed to establish four key aspects of coastal erosion within Scotland: the physical susceptibility of the coast to erosion; the assets exposed to coastal erosion; the vulnerability of communities to coastal erosion; and the coastal erosion risk to those communities. Coastal erosion susceptibility was modelled here within a GIS, using data for ground elevation, rockhead elevation, wave exposure and proximity to the open coast. Combining these data produced the Underlying Physical Susceptibility Model (UPSM), in the form of a 50 m2 raster of national coverage. The Coastal Erosion Susceptibility Model (CESM) was produced with the addition of sediment supply and coastal defence data, which then moderates the outputs of the UPSM. Asset data for dwellings, key assets, transport infrastructure, historic assets, and natural assets were used along with the UPSM and CESM to assess their degree of exposure to coastal erosion. A Coastal Erosion Vulnerability Model (CEVM) was produced using Experian Mosaic Scotland (a geodemographic classification which identifies 44 different social groups within Scotland) to classify populations based upon 11 vulnerability variables. Dwellings were assigned a CESM and CEVM score in order to establish their coastal erosion risk. This research demonstrated that the issue of coastal erosion will impact on a relatively low number of properties compared to those impacted by flooding (both coastal and fluvial) as many dwellings are already protected by coastal defences. There is therefore, a considerable future liability, and great pressure for coastal defences to be maintained and upgraded in their current form. The use of the CEVM is a novel inclusion within a coastal erosion assessment for Scotland. Use of the CEVM established that coastal erosion risk is not distributed equally amongst the Scottish coastal population and highlighted that risk can be reduced by either reducing exposure or reducing vulnerability. Thus far in Scotland, reducing exposure has been the primary management approach, which has a number of implications with regards social justice. This research identified the existing data gaps that should be addressed by future research in order to further improve coastal management in Scotland. Future research should focus on assessing historical coastal change rates on a national scale, improve modelling of national scale wave exposure, enhance the information held about current coastal defences and, determine the direct and indirect economic cost associated with the loss of different asset types. It is also necessary to clarify the social justice implications of using adaptation approaches to manage coastal erosion as well as establishing a method to communicate the susceptibility, exposure, vulnerability and risk aspects whilst minimising the potential negative impacts (e.g. property blight) of releasing such information.

Effect of bleaching agents containing fluoride or calcium on enamel microhardness, roughness and permeability

Aim: To evaluate the effect of different in-office bleaching agents on the permeability, roughness and surface microhardness of human enamel. Methods: For evaluation of roughness and microhardness, 40 hemi-faces of 20 premolars were subjected to initial roughness (Ra parameter) and microhardness (VHN) measurements. Thirty-two premolar’s crowns were used for permeability test. Then, all specimens were randomly divided into four groups: C - without bleaching (control), HP35 - bleaching with 35% hydrogen peroxide (HP), HPF38 - 38% HP+fluoride, HPC35 - 35% HP+calcium. Final roughness (FR) and microhardness (FM) measurements were evaluated. For permeability, the 32 crowns were immersed in 1% sodium hypochlorite (20 min) and silver nitrate solutions (2 h) and subjected to developing solution under fluorescent light (16 h). Three sections from the crowns were analyzed in light microscope (100x) to evaluate the scores of permeability: Score 0 - no tracer agent penetration; Score 1 - less than half the thickness of enamel penetration; Score 2 - tracer agent reaching half the enamel thickness; Score 3 - entire enamel depth penetration, without reaching dentin and Score 4 - tracer agent reaching dentin. For roughness and microhardness evaluation were used one-way ANOVA and Dunnet post-test for independent samples, and t test for paired samples. For permeability, the data were analyzed by Kruskal Wallis and Dunn tests. Results: A significantly higher permeability and surface roughness were observed in groups HP35, HPF38 and HPC35 compared to the C group, as well as decreased microhardness (p<0.05). Conclusions: All bleaching agents increased permeability and surface roughness, and decreased microhardness of human enamel; thus, the addition of fluoride or calcium was not beneficial.

Distinguishing predisposing factors for enamel hypoplasia and molar-incisor hypomineralization in children in Ile-Ife, Nigeria

Aim: To determine if the prevalence of enamel hypoplasia, molar-incisor hypomineralisation (MIH) and deciduous molar hypomineralisation (DMH) is associated with the socioeconomic status of the child and to determine the prevalence of enamel hypoplasia and MIH/DMH comorbidity in the study population. Methods: Information was collected on the sex and socioeconomic status of the 1,169 study participants’ resident in Ile-Ife, Nigeria, recruited through a household survey. The children were clinically examined to assess for the presence of enamel hypoplasia, MIH and DMH. Associations between sex, socioeconomic status and the prevalence of enamel hypoplasia, MIH and DMH were determined. The proportion of children with enamel hypoplasia and MIH/DMH co-morbidity was also determined. Results: Among the 1,169 study participants, 47(4.0%) had MIH, 15 (1.3%) had DMH and 161 (13.8%) had enamel hypoplasia. One (0.09%) study participant had MIH/DMH co-morbidity, 12 (1.0%) had DMH/enamel hypoplasia co-morbidity, and 9 (0.8%) had MIH/hypoplasia co-morbidity. There was no significant association between the socioeconomic status and presence of enamel hypoplasia (p=0.22), MIH (p=0.78) or DMH (p=1.00). Conclusions: The socioeconomic status cannot be used as a distinguishing factor for enamel hypoplasia, MIH and DMH. The possibility of co-existence of enamel hypoplasia and MIH/DMH makes it imperative to find ways to distinguish between the lesions.

Erosão dentária na adolescência

Com o presente trabalho, pretende-se perceber qual a relação do estilo de vida, hábitos alimentares e doenças sistémicas dos adolescentes com a erosão dentária, e quais são as melhores formas de prevenção e tratamento. É na fase da adolescência que começa a haver uma maior preocupação com o corpo e que começam a surgir alguns extremos de consumo alimentar, que podem caracterizar-se em desordens alimentares afetando diretamente a saúde oral, podendo causar erosão dentária. É também na adolescência que a prática de atividade desportiva aumenta, podendo também ter impacto no desenvolvimento desta patologia. A erosão dentária começa com a desmineralização das camadas superficiais do esmalte, podendo evoluir para perda significativa da estrutura dentária. Os ácidos responsáveis pela erosão dentária podem ter origem extrínseca ou intrínseca. Enquanto os fatores extrínsecos estão relacionados com hábitos alimentares e estilo de vida, os fatores intrínsecos podem ser provocados por doenças sistémicas. O fator fundamental da prevenção da erosão dentária é a diminuição da frequência e da severidade do ataque ácido. No entanto, pela sua etiologia multifatorial, muitas vezes este controlo torna-se difícil. Em relação ao tratamento, existem diferentes opções dependendo do grau da lesão, mas um diagnóstico precoce é o fator chave neste processo. É importante referir que a monitorização e o controlo periódico do paciente deverão ser realizados com o objetivo de promover a sua saúde e prevenir o aparecimento de novas lesões.

EROSION DE SUELOS ENCERVATANA DE PURISCAL 1990-1995

Durante el periodo de 1990-1995 en la localidad de Cerbatana de Puriscal, Costa Rica, Se instalo un experimento en parcelas y microcuencas de escorrentía y erosión con el objetivo de monitorear sistemáticamente la pérdida de suelo en cultivos de café, maíz, frijol- tabaco y en pastizales bajo las condiciones habituales de manejo utilizadas por el agricultor. Los resultados resaltan que las obras de conservación aplicadas para los cafetales son eficientes en la reducción de la erosión y escorrentías a montos relativamente aceptables y (manejables); mientras que estas mismas obras de conservación no son suficientes para reducir la erosión en cultivos de rotación como el maíz-frijol-tabaco, ya que el factor de cobertura vegetal insuficientes para amortiguar el poder de desprendimiento de las gotas de lluvia. De igual manera se deduce de los resultados que los pastos son una buena alternativa para la protección de los suelos, siempre y cuando su espacio se aproveche en combinación con coberturas arbóreas como cítricos y se evite el sobrepastoreo. Se demuestra, además, que para la zona de Puriscal, el factor uso y manejo de suelo y cultivos es el que mayor influencia tiene sobre la perdida de suelos, en comparación con las particularidades correspondientes a las condiciones climáticas y características fisicoquímicas de los suelos.

LA ECUACION UNIVERSAL DE EROSION

La erosión de los suelos agrícolas, la protección del manto vegetal en laderas inclinadas, la conservación de la fauna son temas de actualidad nacional y de problemática incluida como tema de análisis o discusión en los programas de varias carreras universitarias. El autor desea aportar elementos de juicio para enfrentar científicamente el problema de la erosión edáfica; para “ el control de un fenómeno físico o mecánico no se lleva a buen termino si el proceso de desarrollo del fenómeno no es entendido, los factores que lo determinan no pueden ser medidos y las mediciones presentadas en una ecuación”. En este artículo se hace revisión de los intentos para cuantificar el fenómeno mediante la aplicación de la Ecuación Universal de Perdida de Suelo. ABSTRACT The erosion of agricultural soils, protection of the natural cover on sloping and wild life conservation are now national issues and they are principal subjets of several courses in the universities. The author wants to contribute with some viewpoints or how to scientifically take up the problem of edaphic erosion. For him, “the control of the physical ormechanical phenomenon is not well carried out if the processes involved in the phenomenon itself are not undertood, or the determining factor are not measured and written down in a equation”. This paper reviews the attempts of quantifying the phenomenon by the application of the Universal Equitation of Equation of Soil Loss.

EROSION Y CONSERVACIÓN DE SUELOS EN COSTA RICA. ALGUNOS RESULTADOS DEL TALLER DE EROSIÓN DE SUELOS

En este artículo, se resumen los resultados de las discusiones sostenidas durante el Taller de Erosión de Suelos, celebrado en el mes de julio de 1991 en la Universidad Nacional, Heredia, Costa Rica.    Una gran parte de la discusión se centró en la aplicabilidad de modelos para el análisis de la erosión en condiciones tropicales.  En este campo, se debe cambiar de la Ecuación Universal de Pérdida de Suelo, que está fuera de su rango de calibración y que produce valores no confiables, a modelos físicoss como OPUS, EPIC o con más aplicabilidad, los modelos del WEPP.  Como alternativas para un análisis muy preliminar de la susceptibilidad a la erosión en regiones con poca información deben analizarse métodos morfométricos y goemorfológico.  Las coberturas parecer ser la mejor y más barata protección del suelo contra la erosión y daños en el sitio, las supuestas desventajas deben analizarse a más detalle.  Deben analizarse y protegerse los caminos y carreteras en una manera más amplia, por que son muchas veces las fuentes principales de escorrentía superficial. 

Farm it right : the sustainable farming simulation

Farm It Right is an innovative creative work that simulates sustainable farming techniques using ecological models prepared by academics at Bradford University (School of Life Sciences). This interactive work simulates the farming conditions and options of our ancestors and demonstrates the direct impact their actions had on their environment and on the ’future of their cultures’ (Schmidt 2008). Specifically, the simulation allows users to explore and experiment with the complex relationships between environmental factors and human decision making within the harsh conditions of an early (9th century) Nordic farm. The simulation interface displays both statistical and graphical feedback in response to the users selections regarding animal reproduction rates, shelter provisions, food supplies etc. as well as demonstrating resulting impacts to soil erosion, water supply, animal population sizes etc.---------- 'Farm It Right' is now used at Bradford University (School of Life Sciences) as a dynamic e-Learning resource for incorporating environmental archaeology with sustainable development education, improving the engagement with complex data and the appreciation of human impacts on the environment and the future of their cultures. 'Farm It Right' is also demonstrated as an exemplar case study for interaction design students at Queensland University of Technology.

Case-control study of early childhood caries in Australia

The aim of this case-control study of 617 children was to investigate early childhood caries (ECC) risk indicators in a non-fluoridated region in Australia. ECC cases were recruited from childcare facilities, public hospitals and private specialist clinics to source children from different socioeconomic backgrounds. Non-ECC controls were recruited from the same childcare facilities. A multinomial logistic modelling approach was used for statistical analysis. The results showed that a large percentage of children tested positive for Streptococcus mutans if their mothers also tested positive. A common risk indicator found in ECC children from childcare facilities and public hospitals was visible plaque (OR 4.1, 95% CI 1.0-15.9, and OR 8.7, 95% CI 2.3-32.9, respectively). Compared to ECC-free controls, the risk indicators specific to childcare cases were enamel hypoplasia (OR 4.2, 95% CI 1.0-18.3), difficulty in cleaning child's teeth (OR 6.6, 95% CI 2.2-19.8), presence of S. mutans (OR 4.8, 95% CI 0.7-32.6), sweetened drinks (OR 4.0, 95% CI 1.2-13.6) and maternal anxiety (OR 5.1, 95% CI 1.1-25.0). Risk indicators specific to public hospital cases were S. mutans presence in child (OR 7.7, 95% CI 1.3-44.6) or mother (OR 8.1, 95% CI 0.9-72.4), ethnicity (OR 5.6, 95% CI 1.4-22.1), and access of mother to pension or health care card (OR 20.5, 95% CI 3.5-119.9). By contrast, a history of chronic ear infections was found to be protective for ECC in childcare children (OR 0.28, 95% CI 0.09-0.82). The biological, socioeconomic and maternal risk indicators demonstrated in the present study can be employed in models of ECC that can be usefully applied for future longitudinal studies.

Evaluation of piezoelectric PVDF polymers for use in space environments. II. Effects of atomic oxygen and vacuum UV exposure

The effects of atomic oxygen (AO) and vacuum UV radiation simulating low Earth orbit conditions on two commercially available piezoelectric polymer films, poly(vinylidene fluoride) (PVDF) and poly(vinylidene fluoride-trifluoroethylene) P(VDF-TrFE), have been studied. Surface erosion and pattern development are significant for both polymers. Erosion yields were determined as 2.8 � 10�24 cm3/atom for PVDF and 2.5 � 10�24 cm3/atom for P(VDF-TrFE). The piezoelectric properties of the residual material of both polymers were largely unchanged after exposure, although a slight shift in the Curie transition of the P(VDF-TrFE) was observed. A lightly cross-linked network was formed in the copolymer presumably because of penetrating vacuum ultraviolet (VUV) radiation, while the homopolymer remained uncross-linked. These differences were attributed to varying degrees of crystallinity and potentially greater absorption, and hence damage, of VUV radiation in P(VDFTrFE) compared with PVDF.