title: Structure-property relationships in hybrid dental nanocomposite resins containing monofunctional and multifunctional polyhedral oligomeric silsesquioxanes.
abstract: Organic-inorganic hybrid materials, such as polyhedral oligomeric silsesquioxanes (POSS), have the potential to improve the mechanical properties of the methacrylate-based composites and resins used in dentistry. In this article, nanocomposites of methacryl isobutyl POSS (MI-POSS [bears only one methacrylate functional group]) and methacryl POSS (MA-POSS [bears eight methacrylate functional groups]) were investigated to determine the effect of structures on the properties of dental resin. The structures of the POSS-containing networks were determined by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. Monofunctional POSS showed a strong tendency toward aggregation and crystallization, while multifunctional POSS showed higher miscibility with the dimethacrylate monomer. The mechanical properties and wear resistance decreased with increasing amounts of MI-POSS, indicating that the MI-POSS agglomerates act as the mechanical weak point in the dental resins. The addition of small amounts of MA-POSS improved the mechanical and shrinkage properties. However, samples with a higher MA-POSS concentration showed lower flexural strength and flexural modulus, indicating that there is a limited range in which the reinforcement properties of MA-POSS can operate. This concentration dependence is attributed to phase separation at higher concentrations of POSS, which affects the structural integrity, and thus, the mechanical and shrinkage properties of the dental resin. Our results show that resin with 3% MA-POSS is a potential candidate for resin-based dental materials.
authors.affiliation: Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, People's Republic of China.
authors.forename: Weiguo
authors.initials: W
authors.lastname: Wang
authors.affiliation: Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, People's Republic of China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Sun
authors.affiliation: Department of General Dentistry and Emergency, School of Stomatology, Fourth Military Medical University, Xi'an, People's Republic of China.
authors.forename: Li
authors.initials: L
authors.lastname: Huang
authors.affiliation: Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, People's Republic of China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Gao
authors.affiliation: Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, People's Republic of China.
authors.forename: Jinghao
authors.initials: J
authors.lastname: Ban
authors.affiliation: Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, People's Republic of China.
authors.forename: Lijuan
authors.initials: L
authors.lastname: Shen
authors.affiliation: Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, People's Republic of China.
authors.forename: Jihua
authors.initials: J
authors.lastname: Chen
mesh_terms: D001696:Biomechanical Phenomena; D019554:Dental Restoration Wear; D006801:Humans; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D015394:Molecular Structure; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure; D050997:Nanomedicine; D017646:Organosilicon Compounds / Q000737:chemistry*; D012117:Resins, Synthetic / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D017646:Organosilicon Compounds; D012117:Resins, Synthetic
keywords: POSS; dental resin; hybrid material; methacrylate monomer; nanocomposite