Secondary caries and restoration fracture remain the two most common problems. The objectives of this study were to develop stress-bearing, fluoride-releasing nanocomposites. Novel CaF2 nanoparticles (56-nm) were synthesized via spray-drying and incorporated into resin with glass co-fillers. F-release increased with increasing nano-CaF2 content, or with decreasing pH (p<0.05). F-release rates at 70-84 days were 1.13 g/(cm2 day) and 0.50 g/(cm2 day) for nanocomposite containing 30% and 20% nano-CaF2, respectively. They matched the 0.65 g/(cm2 day) of a commercial resin-modified glass ionomer (p>0.1). Nanocomposites had flexural strengths of 70-120MPa, after 84-day immersion at pH4, pH5.5, and pH7. These strengths were 3-5 fold that of resin-modified glass ionomer, and matched/exceeded a commercial composite with little F-release. In summary, novel nano-CaF2 with high surface area produced high F-release at low filler-levels, thereby making room in resin for reinforcement glass. This yielded nanocomposites with high F-release and stress-bearing properties, which may help reduce secondary-caries and restoration fracture.
Citation: Journal of Dental Research
Pub Type: Journals
Dental nanocomposite, CaF2 Nanoparticles, Fluoride Release, Stress-bearing, Tooth Caries.