title: New functional and aesthetic composite materials used as an alternative to traditional post materials for the restoration of endodontically treated teeth.
abstract: OBJECTIVE
  To tailor composites of polyethylene-hydroxyapatite to function as a new intracanal post for the restoration of endodontically treated teeth (ETT).
  
  
  METHODS
  Silanated hydroxyapatite (HA) and zirconium dioxide (ZrO2) filled low-density polyethylene (LDPE) composites were fabricated by a melt extrusion process and characterised using infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). The flexural strength and modulus were determined in dry state and post ageing in simulated body fluid and fractured surfaces analysed by SEM. The water uptake and radiographic appearance of the experimental composites were also measured and compared with a commercially known endodontic fibre post. Data were submitted to one-way analysis of variance (ANOVA) and post hoc Tukey multiple comparison tests at a level of significance P<0.05.
  
  
  RESULTS
  The LDPE/HA composites were structurally flexible and the HA content had a significant effect on the flexural strength and modulus. A univariate analysis of variance showed no significant differences in modulus and strength (P<0.05) post accelerated ageing in simulated body fluid with very low water uptake. The melting point of the LDPE/HA composites ranged between 135 and 136°C, which would facilitate removal in case of retreatment using conventional dental heating devices. The inclusion of HA reduced the damping thereby enhancing dimensional stability, whilst the addition of zirconia yielded a semi-translucent material that was sufficiently radiopaque, comparable to commercial posts, thus yielding aesthetic materials.
  
  
  CONCLUSIONS
  Innovative materials for restoration of ETT were developed; offering considerable benefits over the currently available material in terms of biomechanical and thermal properties.
  
  
  CONCLUSIONS
  This study provided a new option for the development of a new intracanal post made up of functional and aesthetic composites.
authors.affiliation: Division of Tissue Engineering & Biophotonics, King's College London Dental Institute, London, UK; Department of Conservative Dentistry, College of Dentistry, University of Baghdad, Baghdad, Iraq.
authors.forename: A
authors.initials: A
authors.lastname: Almaroof
authors.affiliation: Division of Tissue Engineering & Biophotonics, King's College London Dental Institute, London, UK; Department of Conservative Dentistry, College of Dentistry, University of Baghdad, Baghdad, Iraq.
authors.forename: R
authors.initials: R
authors.lastname: Alhashimi
authors.affiliation: Department of Conservative Dentistry, King's College London Dental Institute, London, UK.
authors.forename: F
authors.initials: F
authors.lastname: Mannocci
authors.affiliation: Division of Tissue Engineering & Biophotonics, King's College London Dental Institute, London, UK. Electronic address: sanjukta.deb@kcl.ac.uk.
authors.forename: S
authors.initials: S
authors.lastname: Deb
mesh_terms: D003188:Composite Resins / Q000737:chemistry*; D017886:Durapatite / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D055595:Mechanical Phenomena; D008954:Models, Biological; D020959:Polyethylene / Q000737:chemistry; D019553:Tooth, Nonvital / Q000601:surgery*
chemical_list: D003188:Composite Resins; D020959:Polyethylene; D017886:Durapatite
keywords: Dental post; Melt-extrusion; Polyethylene–hydroxyapatite; Restoration of endodontically treated teeth