IJSR International Journal of Scientific Research 2277 - 8179 Indian Society for Health and Advanced Research ijsr-7-5-15295 Original Research Paper Effect of pH of Immersion Media and Length of Immersion Period on Elemental Ion Release from Commercially available Ni-Cr Alloys: An in vitro study Sharanya Gupta Dr. Dr. Samarth Kumar Agarwal Dr. May 2018 7 5 01 02 ABSTRACT

 Purpose: Biocompatibility of dental casting alloys is of paramount importance in rendering successful treatment to the patients. Controversies

have been cited in literature related to elemental ion release based on pH and length of immersion period. Hence the study was conducted with the
purpose of evaluating the effect of the pH of immersion media and length of immersion period on the release of elemental ions from the
commercially available Ni–Cr alloys.
Materials and Methods: A total of 270 disc shaped specimens (5 mm x 3 mm) were prepared from 2 commercially available Ni–Cr alloys. One
hundred and thirty five samples were fabricated per alloy which were divided into three groups of 15 each. The samples were immersed in
immersion media of pH 4.0, 6.8 and 8.0 for time intervals of 1 hour, 1 day and 1 month. The elemental ion release was estimated using inductively
coupled plasma atomic spectrophotometer.
Results: The elemental ion release of the major elements increased significantly (p < 0.05) from both alloys with decrease in the pH of the
immersion media. Maximum ion release was seen at pH 4.0 followed by pH 8.0 and 6.7. Significant increase (p < 0.05) in the elemental ion release
was seen only at an acidic pH of 4.0 when the release at 1 month was compared with 1 hour and 1 day.
Conclusion: Decrease in pH of immersion media and increase in the length of immersion period led to increase in the elemental ion release from
commercially available Ni–Cr alloys.