title: Fracture resistance of cementum-extended composite fillings in severely damaged deciduous incisors: An in vitro study.
abstract: OBJECTIVE
  The aim of this study was to comparatively assess the fracture resistance of the cementum-extended and conventional composite fillings with or without intracanal composite posts in severely damaged deciduous incisors.
  
  
  METHODS
  This in vitro study was performed on 60 extracted deciduous maxillary incisors that were randomly divided into four groups: Group 1: Composite filling (CF); Group 2: Composite filling with composite posts (CF + CP); Group 3: Composite filling extended 0.5 mm to cementum (ceCF); Group 4: Composite filling extended 0.5 mm to cementum with composite posts (ceCF + CP). The fracture resistance was assessed by exerting a progressively increasing load with a cross-head speed of 0.5 mm/min in a Universal Testing Machine.
  
  
  METHODS
  Data were analyzed by SPSS-18 using one-way analysis of variance at α < 0.05.
  
  
  RESULTS
  The mean fracture resistance (MFR) values of the experimental groups were 410.57 ± 139.44 N, 564.44 ± 92.63 N, 507.5 ± 76.37 N and 601.08 ± 96.04 N. A significant difference was found between the MFR of Groups 1 and 2, Groups 1 and 4 and Groups 3 and 4 (P < 0.05).
  
  
  CONCLUSIONS
  A superior outcome was achieved by intracanal composite posts in both conventional and cementum-extended composite fillings.
authors.affiliation: Dental Research Center, Department of Pediatric Dentistry, Tehran, Iran.
authors.forename: Bahman
authors.initials: B
authors.lastname: Seraj
authors.affiliation: Dental Student's Scientific Research Center, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Sara
authors.initials: S
authors.lastname: Ehsani
authors.affiliation: Department of Pediatric Dentistry, School of Dentistry, Babol University of Medical Sciences, Babol, Iran.
authors.forename: Shirin
authors.initials: S
authors.lastname: Taravati
authors.affiliation: Laser Research Center of Dentistry, Department of Pediatric Dentistry, Tehran, Iran.
authors.forename: Sara
authors.initials: S
authors.lastname: Ghadimi
authors.affiliation: Department of Dental Biomaterials, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mostafa
authors.initials: M
authors.lastname: Fatemi
authors.affiliation: Dentist, Tehran, Iran.
authors.forename: Sahar
authors.initials: S
authors.lastname: Safa
keywords: Composite resins; deciduous teeth; fracture resistance; post and core technique