title: High-aspect ratio fillers: fiber-reinforced composites and their anisotropic properties.
abstract: OBJECTIVE
  To present an overview of fiber-reinforced composites (FRCs) that are a group of non-metallic dental biomaterials used in several fields of dentistry.
  
  
  METHODS
  A range of relevant publications from the past half century are surveyed, with emphasis upon recent publications.
  
  
  RESULTS
  FRCs vary according to the type of fiber fillers and orientation of fibers, the latter being responsible for several properties which can vary from isotropic to anisotropic. The length of the fibers, i.e. the aspect ratio of the filler, is another factor or variable that contributes to the properties and the development of new types of composite resins for restorative and prosthetic dentistry, as well as to reconstructive medicine.
  
  
  CONCLUSIONS
  Understanding the anisotropic nature of FRCs from the perspective of dental applications has increased in recent years. This review describes some fiber orientation related anisotropic properties of FRCs which contribute to the increased use of FRCs in clinical dentistry.
authors.affiliation: Department of Biomaterials Science and Turku Clinical Biomaterials Centre - TCBC, Institute of Dentistry, University of Turku, Turku, Finland. Electronic address: Pekka.vallittu@utu.fi.
authors.forename: Pekka K
authors.initials: PK
authors.lastname: Vallittu
mesh_terms: D016880:Anisotropy; D003188:Composite Resins / Q000737:chemistry*; D003764:Dental Materials / Q000737:chemistry*; D003799:Dental Stress Analysis; D008422:Materials Testing; D013499:Surface Properties
chemical_list: D003188:Composite Resins; D003764:Dental Materials
keywords: Anisotropicity; Composites; Fiber; Fiber-reinforced composite; Polymer