Influence of restorative procedures on endodontically treated premolars: Finite element analysis of a CT-scan based three-dimensional model

Abstract

An endodontically treated tooth with mesial-occlusal-distal (MOD) cavity is often restored with composite resin. Palatal and buccal cusp reduction (MODP, MODPB), and/or fiber-reinforced composite posts (P), are used in an attempt to improve the longevity of the restoration. The aim of this study was to determine the effects of these procedures on von Mises stress values and distribution in dental tissues and restorative materials using finite element analysis. Based on CT scans of an extracted second upper premolar, six 3D endodontically treated tooth models (MOD, MODP, MODPB, MOD+P, MODP+P, MODPB+P) were created. Each model was subjected to a summary force of 150 N on the occlusal surface simulating the normal biting pattern and maximal von Mises stresses were calculated. MODP seems to reduce von Mises stress values in dental tissues and P seems to transfer some of the stresses from dental tissues to the composite filling.

Finite element and in vitro study on biomechanical behavior of endodontically treated premolars restored with direct or indirect composite restorations

“…Actually, the crown cement layer in the EC models showed a similar maximum strain value as the enamel in the DR models. Hence, it seems that the cement layer “buffered” the strain of enamel under the endocrown, possibly due to the lower elastic modulus compared to both the crown and the enamel, which could lead to better preservation of the enamel tissue during fatigue loading in teeth restored with endocrowns compared to direct restorations 3 .…”

“…Research was performed in accordance with the Declaration of Helsinki. The detailed model generation procedure was described elsewhere 3 , 4 . In brief, there were 42 sections in the z-axis that represented tooth tissues and were transferred to a segmentation software (Amira; Thermo Fisher Scientific, Waltham, MA, USA) in the DICOM format.…”

Effect of Fiber Posts on Stress Distribution of Endodontically Treated Upper Premolars: Finite Element Analysis

“…Moreover, the preparation of an endodontic access cavity increases the possibility of cusp fractures following the cusp deflection during function [ 69 ], which is higher for endodontically treated premolars with MOD preparations [ 70 , 71 ]. In fact, it has been observed how the loss of the marginal walls makes these teeth extremely prone to fracture [ 10 , 28 , 52 ]. For all the above reasons, premolars might hypothetically require fiber posts more often than molars, especially in the presence of MOD cavities [ 5 , 52 ].…”

“…Recently, on the other hand, an increasing number of papers have been advocating the use of direct composite restorations without any post for ETT [ 28 , 29 , 30 , 31 , 32 ], stressing the concept that the purpose of a post should be just to retain the core (whenever required) instead of increasing the intrinsic resistance of the root [ 33 , 34 ]; the introduction of innovative and advanced resin-based restorative materials would probably make such a clinical approach even more reliable. Nowadays, in fact, emerging nanotechnologies and improved nanoscale knowledge allows the characterization and control of materials at the atomic or molecular level on a scale of less than 100 nm [ 35 , 36 ].…”

A literature review on the linear elastic material properties assigned in finite element analyses in dental research

“…, 41.4 GPa (36,37), 46.8 GPa (38), 48.0 GPa (39), 50.0 GPa (40), 60.0 GPa (41), 72.7 GPa (42)(43)(44) 75-100 GPa (45), 77.9 GPa (46)(47)(48), 80.0 GPa (49)(50)(51)(52)(53)(54)(55)(56), 82.0 GPa (41), 82.5 GPa (57), 83.0 GPa (58) 84.0 GPa (59)(60)(61)(62)(63)(64), 84.1 GPa (5,46,61,, 85.0 GPa (107), 0.002 (77) 0.2 (75,76,78,85,86,96,97,102), 0.23-0.30 (108), 0.30 (25-27,29,30,32,34-38,40,49-51,53,56,61,62,73,74,79,87,88,93,95,98,99 ,103,109,110), 0.31 (28,52,89,111,…”