Ivan N. Bastos

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OBJECTIVE Dental implants are usually made from commercially pure titanium or titanium alloys. The aim of this investigation was to determine the influence of surface treatments of commercially pure titanium samples on in vitro bioactivity. METHODS Commercially pure (cp) titanium (Ti) sheets were submitted to three different surface treatments, including,(More)
In this study Ti-6Al-4V samples were used as substrates and Ca-P layers were deposited using sol-gel technique and covered by spin-coating. The efficiency of hydroxyapatite (HA) coatings as drug carrier was also evaluated by immersion in gentamicin sulphate solution and the release profiles were obtained by cumulative method of the coating samples. Three(More)
Several experimental measurements are expressed in the form of one-dimensional profiles, for which there is a scarcity of methodologies able to classify the pertinence of a given result to a specific group. The polarization curves that evaluate the corrosion kinetics of electrodes in corrosive media are an application where the behavior is chiefly analyzed(More)
Dynamics of surface roughness during polycrystalline pure iron electrodissolution is investigated at constant current density by means of ex situ atomic force microscopy. The scaling of the local surface width reveals that surface kinetic roughening is anomalous with both the exponents of local roughness, alpha(loc) , and growth, beta , close to 1 pointing(More)
STATEMENT OF THE PROBLEM Fixed prosthesis and partial dental prosthesis frameworks are usually made from welded Ni-Cr-based alloys. These structures can corrode in saliva and have to be investigated to establish their safety. PURPOSE The purpose of this study was to evaluate the corrosion behavior of joints joined by tungsten inert gas (TIG) welding and(More)
Titanium alloys are used in biomedical implants, as well as in other applications, due to the excellent combination of corrosion resistance and mechanical properties. However, the tribocorrosion resistance of titanium alloy is normally not satisfactory. Therefore, surface modification is a way to improve this specific performance. In the present paper,(More)
The kinetic roughening of dissolving polycrystalline pure iron has been studied. A depth analysis of surface images has shown two consecutive growth regimes characterized by different scaling anomalous properties: an initial intrinsic anomalous scaling evolving in the thick film limit towards the theoretically conjectured faceted anomalous scaling. This(More)
Photocured dental resins are used extensively in restorative procedures in dentistry. Inadequate curing reduces the lifetime of the dental restoration, and consequently it is essential to precisely measure the polymerisation kinetics. In this study, two techniques, Quartz Crystal Microbalance (QCM) and Photoacoustic Spectroscopy (PAS), were used to monitor(More)
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