SDI Company introduces a new generation of ammonia-free water-based silver fluoride solution - Riva Star Aqua. Riva Star Aqua (contains 38% AgF) is a two-step, non-invasive, patented system that serves to provide immediate relief from tooth sensitivity and is effective at stopping the formation of carious lesions. A clinical study confirms a two-year sensitivity reduction effect after a single application of Riva Star Aqua.