Paulo César Freitas Santos-Filho1, Crisnicaw Veríssimo2, Luís Henrique Araújo Raposo3, Pedro Yoshito Noritomi MecEng4, Luis Roberto Marcondes Martins5. 1. Department of Restorative Dentistry and Dental Materials, Dentistry School, Federal University of Uberlandia, Minas Gerais, Brazil. Electronic address: paulocesarfs@foufu.ufu.br. 2. Department of Restorative Dentistry and Dental Materials, Dentistry School, Federal University of Uberlandia, Minas Gerais, Brazil. 3. Department of Occlusion, Fixed Prosthodontics and Dental Materials, Dentistry School, Federal University of Uberlandia, Minas Gerais, Brazil. 4. Renato Archer Information Technology Center, Ministry of Science and Technology, Campinas, São Paulo, Brazil. 5. Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas, Piracicaba, São Paulo, Brazil.
Abstract
INTRODUCTION: The aim of this study was to evaluate the influence of a ferrule, post system, and length on the stress distribution of weakened root-filled teeth. METHODS: The investigation was conducted by using 3-dimensional (3D) finite element analysis. A sound tooth and 8 3D models of a weakened root-filled central incisor were generated using computer-aided design/computer-aided manufacturing software. The models were created without a ferrule and with a 2.0-mm ferrule, restored with a relined glass fiber post or a cast post and core (Cpc), and 12.0- and 7.0-mm post lengths. Each 3D model was imported using ∗.STEP files to the finite element software for mesh generation. The models were subjected to 100-N oblique loading at the palatal surface, and the results were evaluated by von Mises criterion and maximum principal stress distribution. RESULTS: Finite element analysis showed that the Cpc models showed elevated stress levels in the root canal regardless of the presence of a ferrule. Relined glass fiber post models showed homogeneous stress distribution to the dentin external surface similar to the sound tooth model. Without a ferrule, Cpc with a 7- or 12-mm length promoted high levels of tensile stress inside the root canal. CONCLUSIONS: Ferrule presence promoted more satisfactory stress distribution to the roots. Post length influenced the stress distribution only for the models restored with a cast post and core. High levels of tensile stress inside the root canals were verified with a cast post and core, which should be avoided to rehabilitate weakened roots, mainly in the absence of a ferrule.
INTRODUCTION: The aim of this study was to evaluate the influence of a ferrule, post system, and length on the stress distribution of weakened root-filled teeth. METHODS: The investigation was conducted by using 3-dimensional (3D) finite element analysis. A sound tooth and 8 3D models of a weakened root-filled central incisor were generated using computer-aided design/computer-aided manufacturing software. The models were created without a ferrule and with a 2.0-mm ferrule, restored with a relined glass fiber post or a cast post and core (Cpc), and 12.0- and 7.0-mm post lengths. Each 3D model was imported using ∗.STEP files to the finite element software for mesh generation. The models were subjected to 100-N oblique loading at the palatal surface, and the results were evaluated by von Mises criterion and maximum principal stress distribution. RESULTS: Finite element analysis showed that the Cpc models showed elevated stress levels in the root canal regardless of the presence of a ferrule. Relined glass fiber post models showed homogeneous stress distribution to the dentin external surface similar to the sound tooth model. Without a ferrule, Cpc with a 7- or 12-mm length promoted high levels of tensile stress inside the root canal. CONCLUSIONS: Ferrule presence promoted more satisfactory stress distribution to the roots. Post length influenced the stress distribution only for the models restored with a cast post and core. High levels of tensile stress inside the root canals were verified with a cast post and core, which should be avoided to rehabilitate weakened roots, mainly in the absence of a ferrule.
Authors: Ana Belén Dablanca-Blanco; Juan Blanco-Carrión; Benjamín Martín-Biedma; Purificación Varela-Patiño; Alba Bello-Castro; Pablo Castelo-Baz Journal: Restor Dent Endod Date: 2017-08-03
Authors: Khalid M Abdelaziz; Cinderella K Keshk; Abdulkhaliq Alshadidi; Salman Mafraq; David F Murchison Journal: J Int Soc Prev Community Dent Date: 2018-02-22