Evaluation of Silver Ion Release from Silver-containing Elastomers in Artificial Saliva

Abstract

The aim of this in-vitro investigation was to determine the amount and pattern of silver ion release from silver-containing elastomers in artificial saliva. Open group (n=10, the cap of each bottle was opened on a regular basis during the experiment) and Seal groups (n=40, the cap of the bottle was remained closed throughout the experiment) consisted of polystyrene bottles containing 2mL of artificial saliva maintained at 37℃ in oven with 20silver-containing elastomers stretched over stainless steel brackets placed in each individual bottles. A polystyrene bottle containing only artificial saliva and 20 stainless steel brackets was used as control. The amount of silver ion release was measured once a day for 7 days (T1 - T7) and then once a week (T8 - T10) for the following 3 weeks in Open group. After the supernatant solution was decanted to measure the amount of ion release,fresh artificial saliva was added in each bottle. In Seal groups (S - 1, 2, 3, 4), cumulative silver ion was measured after 1, 2, 3 and 4 weeks for each group without changing sample solutions. Control was also measured after 4 weeks. Following results were obtained. The silver-containing elastomer showed a high initial silver ion release during the first week and showed declining tendency in the amount of silver ion release over the time period in both Open and Seal groups. Open group showed higher amount of daily ion release than Seal groups which may be attributed to the oxygen contact in Open group. Thus, the initial burst of silver ion release and the varying conditions of oral environment should be taken into consideration in the clinical use of silver-containing elastomer.