a dual component chlorhexidine dentifrice composition of improved shelf stability in which the first component is a gel containing a bis - biguanide antibacterial agent in which the gel vehicle is thickened with a cellulose polymer and the second component is a paste containing a silica abrasive wherein the bis - biguanide antibacterial agent provides undiminished antiplaque and antigingivitis effect with reduced staining when the physically separated components are combined and mixed upon application to dental tissue .