title: Scratch and abrasion properties of polyurethane-based micro- and nano-hybrid obturation materials.
abstract: Polyurethane-based micro- and nano-hybrid composites were produced with controlled porosity to be used as obturation materials. In addition to hydroxyapatite (HAp) micro-particles in the composites, two different ceramics particle types were also added: alumina micro-particles and silica nano-particles. Particles of different sizes provide the materials with improved mechanical properties: the use of micro- and nano-particles produces a better packing because the nano-particles fill the interstitial space left by the micro-particles, rendering an improvement in the mechanical properties. The silica and alumina particles provide the materials with appropriate abrasion and scratching properties, while the HAp provides the required bio-acceptance. The polymeric matrix was a mono-component solvent-free polyurethane. The porosity was selected by controlling the chemical reaction.
authors.affiliation: Centro de Fisica Aplicada y Tecnología Avanzada (CFATA), Universidad Nacional Autonoma de Mexico, Campus Juriquilla, Queretaro 04510, CP 76230, Mexico.
authors.forename: Miriam
authors.initials: M
authors.lastname: Estevez
authors.forename: J Rogelio
authors.initials: JR
authors.lastname: Rodriguez
authors.forename: Susana
authors.initials: S
authors.lastname: Vargas
authors.forename: J A
authors.initials: JA
authors.lastname: Guerra
authors.forename: Witold
authors.initials: W
authors.lastname: Brostow
authors.forename: Haley E Hagg
authors.initials: HE
authors.lastname: Lobland