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

Volume : VII, Issue : V, May - 2018

Dr. Sharanya Gupta, Dr. Siddhi Tripathi, Dr. Samarth Kumar Agarwal, Dr. Manish Kumar

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 faicated 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.