Specialized channels to control the kinetics of ion release in hydrophobic resin

Abstract

Fluoride, as a model ion, has been clinically used to inhibit the development of secondary carious lesions at the interfaces of restored teeth and demineralization. Controlling of its release kinetic is important in the dental restorative composites with respect to enhance biological activities without side effects. To introduce the channels into composites as specialized channels for continuous and controllable fluoride release, this paper suggests the one-dimensional structure with controllable functions. This specialized structure is generated by the novel development of a coaxially aligned tri-nozzle electrospinning technique. The fluoride source, comminuted sodium fluoride nanoparticles, was encapsulated in poly(methyl methacrylate) sheath. Tuned fluoride release was achieved by hydrophilic poly(acrylic acid) incorporated with the NaF nanosuspension with a hollow structure introduced using an inner fluid (ethylene glycol) in the tri-nozzle system. The structures of the multi-functionalized channels were preserved during UV curing of the polymeric dental restorative composites. The resulting composite resins show long-term release profiles controllable by both poly(acrylic acid) content and the hollow structures, which are based on fluoride diffusion and water ingress. Therefore, the functionalized channel can be applied to control the long-term release of ions in hydrophobic matrix at desirable kinetic.