title: Effects of filler type and content on mechanical properties of photopolymerizable composites measured across two-dimensional combinatorial arrays.
abstract: Multicomponent formulations coupled with complex processing conditions govern the final properties of photopolymerizable dental composites. In this study, a single test substrate was fabricated to support multiple formulations with a gradient in degree of conversion (DC), allowing the evaluation of multiple processing conditions and formulations on one specimen. Mechanical properties and damage response were evaluated as a function of filler type/content and irradiation. DC, surface roughness, modulus, hardness, scratch deformation and cytotoxicity were quantified using techniques including near-infrared spectroscopy, laser confocal scanning microscopy, depth-sensing indentation, scratch testing and cell viability. Scratch parameters (depth, width, percent recovery) were correlated to composite modulus and hardness. Total filler content, nanofiller and irradiation time/intensity all affected the final properties, with the dominant factor for improved properties being a higher DC. This combinatorial platform accelerates the screening of dental composites through the direct comparison of properties and processing conditions across the same sample.
authors.affiliation: National Institute of Standards and Technology, Gaithersburg, MD 20899-8543, USA. slgibson@nist.gov
authors.forename: Sheng
authors.initials: S
authors.lastname: Lin-Gibson
authors.forename: Lipiin
authors.initials: L
authors.lastname: Sung
authors.forename: Aaron M
authors.initials: AM
authors.lastname: Forster
authors.forename: Haiqing
authors.initials: H
authors.lastname: Hu
authors.forename: Yajun
authors.initials: Y
authors.lastname: Cheng
authors.forename: Nancy J
authors.initials: NJ
authors.lastname: Lin
mesh_terms: D020650:Combinatorial Chemistry Techniques / Q000379:methods*; D003188:Composite Resins / Q000737:chemistry* / Q000528:radiation effects*; D055119:Elastic Modulus; D006244:Hardness; D006245:Hardness Tests; D008027:Light; D055115:Light-Curing of Dental Adhesives / Q000379:methods; D008422:Materials Testing; D010777:Photochemistry / Q000379:methods; D013314:Stress, Mechanical; D013499:Surface Properties
chemical_list: D003188:Composite Resins