Determination of the Levels of Some Metal Ions in the Blood, Liver and Kidney of Wistar-Albino Rat after Surgical Implantation of Stainless Steel Arch Bar

Abstract

The study was carried out to determine the accumulated levels of the anticipated major corrosion products of stainless steel (SS) arch bar used for maxillomandibular fixation and the affinity of the corrosion products of SS arch bar for some organs, when it is implanted into the mandible of Wistar albino rat (Rattus norvegicus) for six weeks. Ten experimental rats with implantation and ten control rats were each sacrificed at the end of the six weeks by a 1.5 mL lethal dose of chloroform. The concentrations of Co, Cr, Fe, Mn and Ni in the blood and oven-dried kidney and liver of the two groups were determined using atomic absorption spectrophotometry. The highest mean concentration of Fe ions was accumulated in blood (0.5423 ± 0.0150 mg/kg) and least in the liver (0.4675 ± 0.0060 mg/kg). The accumulated levels of Fe ions in the blood of the experimental and control rat (0.3897 ± 0.0703 mg/kg) are statistically different at P < 0.05. The concentration of Ni ions in the experimental rats was statistically elevated compared to the control. The total metal ions accumulated in the blood and kidney followed the ranking Ni > Fe > Co > Mn, this ranking showed a different trend from that accumulated by the liver Fe > Ni > Mn > Co; though the percentage composition of these metals in the arch bar has the ranking Fe > Ni >  Cr > Mn > Co. Ni showed a high affinity for kidney and blood of the rat, while Fe showed affinity for all the organs studied. Ni ions released from SS arch bar was statistically elevated in kidney and Fe ions in blood of the experimental animal model. The study affirms that SS arch wire like other medical implants corrode when bathe by bio-fluids with small amounts of metal ions being accumulated by surrounding organs.