Influence of customized composite resin fibreglass posts on the mechanics of restored treated teeth

• Published in: International endodontic journal 2012-02, Vol.45 (2), p.146-155
• Main Authors: Anchieta, R. B., Rocha, E. P., Almeida, E. O., Freitas Junior, A. C., Martin Junior, M., Martini, A. P., Archangelo, C. M., Ko, C.-C.
• Format: Article
• Language: English
• Subjects: Adenylate cyclase; Atrophy; Biomechanical Phenomena; Cement; Cementation - methods; Composite Resins - chemistry; Computer programs; Computer Simulation; Dental Materials - chemistry; Dental Prosthesis Design; Dental Pulp Cavity - ultrastructure; Dentin - ultrastructure; Dentistry; Elastic Modulus; fibreglass post; Finite Element Analysis; Glass - chemistry; Humans; Image Processing, Computer-Assisted - methods; Imaging, Three-Dimensional - methods; Incisor - ultrastructure; Incisors; Materials Testing; Mathematical models; Maxilla; Mechanical properties; Mechanical stimuli; mechanics; Models, Biological; periodontal ligament; Periodontal Ligament - physiology; Polymerization; Post and Core Technique - instrumentation; Resin Cements - chemistry; resin-dentine interface; Resins; Retinoblastoma protein; root canal; Shear Strength; software; Stress; Stress, Mechanical; Surface Properties; Teeth; X-Ray Microtomography - methods
• ISSN: 0143-2885; 1365-2591
• DOI: 10.1111/j.1365-2591.2011.01955.x

Anchieta RB, Rocha EP, Almeida EO, Freitas Junior AC, Martin Junior M, Martini AP, Archangelo CM, Ko C‐C. Influence of customized composite resin fibreglass posts on the mechanics of restored treated teeth. International Endodontic Journal, 45, 146–155, 2012. Aim  To evaluate the mechanical behaviour of the dentine/cement/post interface of a maxillary central incisor using the finite element method and to compare the stresses exerted using conventional or customized post cementation techniques. Methodology  Four models of a maxillary central incisor were created using fibreglass posts cemented with several techniques: FGP1, a 1‐mm‐diameter conventionally cemented post; CFGP1, a 1‐mm‐diameter customized composite resin post; FGP2, a 2‐mm‐diameter conventionally cemented post; CFGP2, a 2‐mm‐diameter customized composite resin post. A distributed load of 1N was applied to the lingual aspect of the tooth at 45° to its long axis. Additionally, polymerization shrinkage of 1% was simulated for the resin cement. The surface of the periodontal ligament was fixed in the three axes (X =Y = Z = 0). The maximum principal stress (σmax), minimum principal stress (σmin), equivalent von Mises stress (σvM) and shear stress (σshear) were calculated for the dentine/cement/post interface using finite element software. Results  The peak of σmax for the cement layer occurred first in CFGP1 (1.77 MPa), followed by CFGP2 (0.99), FGP2 (0.44) and FGP1 (0.2). The shrinkage stress (σvM) of the cement layer occurred as follows: FGP1 (35 MPa), FGP2 (34), CFGP1 (30.7) and CFGP2 (30.1). Conclusions  Under incisal loading, the cement layer of customized posts had higher stress concentrations. The conventional posts showed higher stress because of polymerization shrinkage.