Stress distribution on dentin-cement-post interface varying root canal and glass fiber post diameters. A three-dimensional finite element analysis based on micro-C data (original) (raw)
Related papers
Journal of applied oral science : revista FOB
The aim of the present study was to analyze the influence of root canal and glass fiber post diameters on the biomechanical behavior of the dentin/cement/post interface of a root-filled tooth using 3D finite element analysis. Six models were built using micro-CT imaging data and SolidWorks 2007 software, varying the root canal (C) and the glass fiber post (P) diameters: C1P1-C=1 mm and P=1 mm; C2P1-C=2 mm and P=1 mm; C2P2-C=2 mm and P=2 mm; C3P1-C=3 mm and P=1 mm; C3P2-C=3 mm and P=2 mm; and C3P3-C=3 mm and P=3 mm. The numerical analysis was conducted with ANSYS Workbench 10.0. An oblique force (180 N at 45º) was applied to the palatal surface of the central incisor. The periodontal ligament surface was constrained on the three axes (x=y=z=0). Maximum principal stress (σ(max)) values were evaluated for the root dentin, cement layer, and glass fiber post. The most evident stress was observed in the glass fiber post at C3P1 (323 MPa), and the maximum stress in the cement layer occurre...
Influence of Ferrule, Post System, and Length on Stress Distribution of Weakened Root-filled Teeth
Journal of Endodontics, 2014
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 12mm 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. (J Endod 2014;-:1-5)
Healthcare
Background: Endodontic shaping causes stress and strain in the root canal dentin. Dentin microcracks have the potential to be later followed by root fractures occurring under the occlusal load. The aim of our research was to theoretically determine the values of such dentinal states of stress and strain during the endodontic shaping of curved root canals using finite element analysis (FEA). Methods: To highlight the stress concentrations in dentin, two geometric models were created considering the volume of the curved dental root and the contact between the endodontic file and the root canal walls. The application of forces with different values was simulated both on a uniform curved root canal and on a root canal with an apical third curvature of 25° as they would be applied during the preparation of a root canal. Results: In the case of the first model, which was acted upon with a force of 5 N, the deformations of the root canal appeared along the entire working length, reaching t...
Analysis of stress distribution in a vertically condensed maxillary central incisor root canal
Journal of Endodontics, 1995
In this study, the stress distribution in a maxillary central incisor subjected to an endodontic treatment was determined by using a three-dimensional finite-element method. The tooth had a variable root canal cross-sectional area, and the canal was assumed to be filled with vertical condensation. The Clinical practice was simulated by considering the obturation in successive stages. The main aim of the study was to investigate the possibility of fracture due to the obturation process. It was found that, within the limits of the study, the likelihood of a root fracture in such a process is a remote possibility.
Journal of Endodontics, 2010
Introduction: The aim of this study was to investigate and compare stress distribution in various degrees of curved roots with different post and restorations by finite element analysis (FEA). Methods: Sixteen 3dimensional FEA models were created and adapted by using computer software based on external anatomy of mandibular second premolar. A 50-N load was applied. Tensile and compressive stresses were plotted. Results: The stress distribution pattern showed that degrees of root curvature in this study (15, 30, and 45 degrees) had little effect. When the elastic modulus of post and core materials was similar to that of root dentin, tensile stresses were low and concentrated on the external root surface. With higher elastic modulus of materials, tensile stresses were increased and concentrated on the post and post apex. Conclusions: Within the limitations of this study, the suitable restoration in endodontically treated mandibular premolar with limited loss of tooth structure was resin composite that was filled in the coronal third of the root canal. However, when the post and core were indicated, the glass-fiber post and resin composite core were the materials of choice for restoration. (
The Journal of prosthetic dentistry, 2017
In post-core crown restorations, the use of flexible posts concentrates stresses at the dentin and the use of stiff posts concentrates stresses at the interfaces. A class of inhomogeneous materials (called functionally graded materials) has been proposed for posts to resolve the weaknesses of both flexible and rigid posts. The purpose of this in vitro study was to design an inhomogeneous post and investigate its influence on the stress distribution of post-core crown restorations. An extracted tooth was mounted, sectioned, and photographed to create a 3-dimensional model of the first premolar tooth. The post-core crown restoration was modeled with and without a ferrule. The surrounding tissues of the mandibular tooth, periodontal ligament, and cortical and trabecular bones were modeled. Fiber-reinforced composite (FRC), metallic, and inhomogeneous posts were investigated by finite element analysis and the stress distribution results compared. FRC posts resulted in the highest maximu...
BMC Oral Health
The purpose of this study is to investigate the effects of different root canal irrigation protocols applied to the dentin and artificial aging procedures on the micro pushout bond strength (mPBS) between dentin and hybrid ceramic posts. Seventy-five single-rooted mandibular premolar teeth were divided into 5 groups (Gr1-5). 50 of the teeth were used for the mPBS tests (n = 10), whereas 25 were used for the smear layer examinations (n = 5). Post space were prepared and irrigated with different irrigation-protocols in each group. (Gr1:[SS], Gr2:[NaOCl] + SS, Gr3:[EDTA] + NaOCl + SS, Gr4:[MA] + NaOCl + SS, Gr5:[Ch] + NaOCl + SS). Post and core pattern were fabricated with pattern resin and a fiber post, after scanning, the posts were milled with Vita Enamic resin ceramic block, and cemented. After 7 days the roots were sliced at thicknesses of 1 mm; half of them were subjected to mPBS test, while the other half were tested after undergoing mechanical cycling for artificial aging. For ...
Stress Distribution in Roots Restored with Fiber Posts and An Experimental Dentin Post: 3D-FEA
Brazilian Dental Journal, 2016
The aim of this study was to compare the stress distribution in radicular dentin of a maxillary canine restored with either a glass fiber post, carbon fiber post or an experimental dentin post using finite element analysis (3D-FEA). Three 3D virtual models of a maxillary canine restored with a metal-ceramic crown and glass fiber post (GFP), carbon fiber post (CFP), and experimental dentin post (DP) were obtained based on micro-CT images. A total of 180 N was applied on the lingual surface of the incisal third of each tooth at 45 degrees. The models were supported by the periodontal ligament fixed in three axes (x=y=z=0). The von Mises stress (VMS) of radicular dentin and the intracanal posts was calculated. The structures of all groups showed similar values (MPa) and distribution of maximum von Mises stress. Higher stress was found in the apical third of dentin while the posts presented homogeneous stress distribution along the axis. The fiber and dentin posts exhibited similar stress values and distribution. Thus, the experimental dentin post is a promising restorative material.