title: Effects of resin formulation and nanofiller surface treatment on the properties of experimental hybrid resin composite.
abstract: This study evaluated the effects of nanofiller surface treatment and resin viscosity on the early and long-term properties of experimental hybrid composites. Three resin formulations (low, medium and high viscosity) were prepared by varying the ratio of TEGDMA:UDMA:bis-GMA (47:33:16 wt%; 30:33:33 wt%; 12:33:51 wt%). Composites contained 71.3 wt% silanated strontium glass (1-3 microm) and 12.6 wt% of either silanated or unsilanated silica (OX-50; 0.04 microm). Specimens (n=10) for flexural strength, flexural modulus, fracture toughness and Knoop hardness were tested after 24 h, 1 and 6 months exposure to water at 37 degrees C. Degree of conversion (DC) was determined 24 h after photoinitiation using FTIR. Resin viscosity only had a marginal influence on the mechanical response of composites but it can be adjusted to achieve a balance between DC and mechanical properties. Adding non-bonded nanofiller to hybrid composites had no systematic effect on DC. Non-bonded nanofillers had no significant effect on the long-term properties of hybrid composites.
authors.affiliation: Department of Biomaterials and Biomechanics, Oregon Health and Science University, 611 SW Campus Dr., Portland, OR 97239, USA. musanjel@ohsu.edu
authors.forename: Lawrence
authors.initials: L
authors.lastname: Musanje
authors.forename: Jack L
authors.initials: JL
authors.lastname: Ferracane
mesh_terms: D020099:Coated Materials, Biocompatible / Q000138:chemical synthesis / Q000737:chemistry*; D003188:Composite Resins / Q000138:chemical synthesis / Q000737:chemistry*; D004548:Elasticity; D005898:Glass / Q000737:chemistry*; D006244:Hardness; D008422:Materials Testing; D036103:Nanotechnology / Q000379:methods*; D012822:Silicon Dioxide / Q000737:chemistry*; D013499:Surface Properties; D014783:Viscosity
chemical_list: D020099:Coated Materials, Biocompatible; D003188:Composite Resins; D012822:Silicon Dioxide