Go natural with Secure Denture Adhesive Secure Denture Adhesive (1x1.4 OZ). Conventional adhesives work by thickening saliva to improve suction between the denture and the gum. The dentures hold only by suction. Being water-soluble, these fixatives can dissolve and wash away when you're eating and drinking, causing dentures to slip and slide. Zinc is an important ingredient in making this work..