Soft denture liner of fluoroethylene copolymer and its clinical evaluation

The acrylic resins are acrylic copolymers to which plasticizers are added occasionally. Inasmuch as the monomers used are generally solvents for the denture base resins, reasonably good adhesion of the liner to the denture should be expected. On the other hand, acrylic soft resins absorb water, swell, and eventually deteriorate; the plasticizer molecules are leached out by the saliva, and the liners gradually harden. Their intraoral efficacy is short lived, and they are not satisfactory for extended clinical use. The silicone rubbers excel in their resiliency and their initial resistance to water absorption. However, in time they also will absorb water and begin to deteriorate. The liners are attached to denture base resins by an adhesive; but the bond is a poor one, and separations between the two materials often occur. Furthermore, they cannot be polished or trimmed properly. Another objection to the silicone lining materials is the possibility of microbial degradation. We developed fluoropolymer soft liners (Kurepeet, Kurecha Co., Tokyo, Japan) that are chemically stable and show good resistance to solvents and abrasion. In addition, their water absorption is low. We have used the liners clinically and observed their behavior in vivo more than 2 years. The objective of this