<b>DETERMINATION OF METAL IONS RELEASED BY STAINLESS STEEL ARCH BAR INTO BIO-FLUIDS</b>

Abstract

The amounts of cobalt, iron, manganese, nickel and chromium ions released from new and reused stainless steel arch bar used for maxillomandibular fixation was determined in Hank's solutions of different hydrogen and chloride ions concentrations, whole blood serum and phosphate buffered saline (PBS) in vitro, over a six-week immersion time at 37 o C, by atomic absorption spectrophotometry. The corrosion levels of the wires due to effects of media and incubation times in the bio-fluids were compared by Duncan's two-way ANOVA (P < 0.05). Pearson's correlation was used in establishing relationship in the amounts of metal ions released by new and reused arch bars. The study indicated that the reused wires released more ions than new ones at all time points. The variation of pH and chloride ions of the bio-fluids had a significant effect on the amount of Ni, Mn and Cr ions released. Ageing prior use of arch bars significantly increased Ni ions released into the bio-fluids.

Stretch to See: Lateral Tension Strongly Determines Cell Survival in Long-Term Cultures of Adult Porcine Retina

“…37,38 Other factors, such as possible metal toxicity, have been considered because nickel, in particular, is known to cause retinal necrosis in vivo. 39 However, based on a study of ion release from stainless steel into biofluids by Joseph et al in 2009, 40 we find it unlikely that the very low levels of metal ions released over the time period, coupled with medium change every second day, strong labeling of a few thin, disorganized fibers as well as some unidentifiable structures in the inner part of the specimen (F). At 10 DIV, stretchcultured explants show strong labeling at the Müller cell end feet as well as weak labeling of thin, slightly disorganized vertical fibers (G).…”

Organic Corrosion Inhibitors

“…There are five primary methods of corrosion control: (I) material selection, (II) design, (III) cathodic protection, (IV) coatings and (V) inhibitors. The simplest method for controlling the corrosion is the selection of the structural materials that change composition, change microstructure stress and eliminate tensile stress [39,40]. Another method is an application of rational design principles which can eliminate many corrosion problems and reduce the time and costs associated with corrosion maintenance and repair [39,40].…”

“…The simplest method for controlling the corrosion is the selection of the structural materials that change composition, change microstructure stress and eliminate tensile stress [39,40]. Another method is an application of rational design principles which can eliminate many corrosion problems and reduce the time and costs associated with corrosion maintenance and repair [39,40]. Cathodic protection is an Organic Corrosion Inhibitors http://dx.doi.org/10.5772/intechopen.72943 electrical method to reduce corrosion rate of metallic structures in electrolytes such as soil or water [42].…”

Synthesis, phase behavior, and simulated in vitro degradation of novel HTPB-b-PEG polyurethane copolymers

“…The Hank's solutions were prepared according to the following composition and mass (concentration) to simulate human body fluids: 26 8.0 g NaCl, 0.4 g KCl, 0.14 g CaCl 2 , 0.35 g NaHCO 3 , 0.1 g MgCl 2 ·6H 2 O, 0.06 g MgSO 4 ·7H 2 O, 0.06 g KH 2 PO 4 , 0.06 g Na 2 HPO 4 , and 1.0 g C 6 H 12 O 6 . All above constituents were dissolved in a certain amount of distilled water and diluted to volume to a 1 L volumetric flask, and the pH value is about 7.4.…”