ABSTRACT
O titânio é um dos 10 mais comuns elementos da terra, existem diferentes pesos atômicos, isótopos estáveis e radioisótopos conhecidos, está presente em ligas comerciais e semicomerciais, sendo que o titânio puro apresenta diferentes graus de pureza. Além disso, as ligas possuem classificações que agregam outros elementos neutros e/ou estabilizadores, são submetidas a diferentes tipos de tratamento de superfícies. Na fabricação dos implantes, o processo industrial da extração da rocha até a colocação na boca pode corromper o grau de pureza. A proposta do presente estudo foi avaliar qualitativamente buracos presentes em 5 implantes dentários brasileiros. As amostras foram preparadas em resina acrílica e realizados cortes sagitais com lâmina de diamante e analisadas no Microscópio Eletrônico de Varredura TM 3030 PLUS TABLESTOP MICROSCOPE HITACHI e reanalisadas no Microscópio Fei Quanta 400. Os resultados evidenciaram que os implantes apresentaram impurezas e estas impurezas podem ser os estabilizadores ou elementos neutros presentes no titânio ou nas ligas utilizadas. Implantodontistas devem ficar alertas sobre a qualidade do implante
Titanium is one of the 10 most common elements of the earth, there are different atomic weights, stable isotopes and known radioisotopes, it is present in commercial and semi-commercial alloys and pure titanium has different degrees of purity. In addition, alloys have classifications that add other neutral elements and/or stabi¬lizers, they are submitted to different types of surface treatments. In manufacturing the implants, the industrial process of extracting the rock into the mouth can corrupt the degree of purity. The purpose of the present study was to qualitatively evaluate holes present in 5 Brazilian dental implants. The samples were prepared in acrylic resin and sagittal cuts with diamond blade and analyzed in the Scanning Electron Microscope TM 3030 PLUS TABLESTOP MICROSCOPE HITACHI and Fei quanta 400. The results showed that the implants presented impurities and these impurities may be the stabilizers or neutral elements present in the titanium or the alloys used. Implant dentists should be alert to the quality of the implant
Subject(s)
Dental Implants , Health Surveillance , Immediate Dental Implant Loading , Consumer AdvocacyABSTRACT
The discovery of arsenic contamination in groundwater has challenged efforts to provide safe drinking-water to households in rural Bangladesh. Two nationally-representative surveys in 2000 and 2002 investigated water-usage patterns, water-testing, knowledge of arsenic poisoning, and behavioural responses to arsenic contamination. Knowledge of arsenicosis rose between the two surveys among women from 42% to 64% but awareness of consequences of arsenic remained limited; only 13% knew that it could lead to death. Behavioural responses to arsenic have been limited, probably in part because of the lack of concern but also because households are uncertain of how best to respond and have a strong preference for tubewell water even when wells are known to be contaminated. Further work conducted by the survey team highlighted the difficulties in providing alternative sources of water, with many households switching back to their original sources of water.