title: Stress analysis of different post-luting systems: a three-dimensional finite element analysis.
abstract: BACKGROUND
  The longevity of endodontically treated teeth is usually determined by the adequacy of root canal treatments, coronal seal and favourable stress distribution within the remaining tooth tissues. The aim of this study was to investigate the influence of post material and luting cement on the biomechanics of endodontically treated teeth using three-dimensional finite element analysis (3-D FEA).
  
  
  METHODS
  A 3 mm section of endodontically treated canine tooth was scanned and reconstructed for 3-D modelling and FE analyses. A metal post (MP) and a glass fibre post (GFP) were tested individually with four luting cements [zinc phosphate (ZPH), glass ionomer (GI), resin modified glass ionomer (RMGI) and resin based cements (RC)]. A push-out test was conducted by subjecting all models to 100 N perpendicular loading at the post.
  
  
  RESULTS
  The maximum stresses generated along the MP-cement interface were significantly higher than corresponding stresses in the GFP-cement interface regardless of the cement type. GFP generated seven times higher stresses within the root dentine than metal posts when ZPH and GI were used, and three times higher when RMGI and RC were used. The displacement of GFP was double (50 μ) the displacement of MP (20 μ) in all groups.
  
  
  CONCLUSIONS
  The low elastic modulus of GFP generated lower stresses along its interface and higher stresses within the root dentine, therefore the probability of debonding and root fracture in the GFP group was lower.
authors: King's College London Dental Institute, Denmark Hill Campus, London, United Kingdom. shihab.romeed@kcl.ac.uk
authors: S A
authors: SA
authors: Romeed
authors: S M
authors: SM
authors: Dunne
mesh_terms: D003481:Cuspid; D003738:Dental Cements; D003739:Dental Cementum; D003799:Dental Stress Analysis / Q000379:methods*; D020342:Finite Element Analysis; D005899:Glass Ionomer Cements; D006801:Humans; D011176:Post and Core Technique; D019279:Resin Cements; D012390:Root Canal Therapy; D014092:Tooth Root; D019553:Tooth, Nonvital
chemical_list: D003738:Dental Cements; D005899:Glass Ionomer Cements; D019279:Resin Cements