Filler leachability during water storage of six composite materials.

Six different dental composite materials were investigated regarding leaching of filler elements such as silicon, barium, and zinc. The leaching was conducted by storing the samples in distilled water at 60 degrees C for half a year. The results could not prove that the leaching behavior of filler elements in most of the investigated cases decreases with time. The practical implications of this study could be important. If other elements follow the same leaching pattern, therapeutic elements such as fluoride could be incorporated in filler particles. The tendency of composites to leach filler elements almost linearly with time, could be used to generate a constant release rate of such therapeutic elements over time. Such an application could have a major impact on controlling caries adjacent to composite restorations and sealants.