J Adv Prosthodont.  2013 Nov;5(4):434-439. 10.4047/jap.2013.5.4.434.

Stress distribution of oval and circular fiber posts in amandibular premolar: a three-dimensional finite element analysis

• Er O
• Kilic K
• Esim E
• Aslan T
• Kilinc HI
• Yildirim S

• KMID: 2176535
• DOI: http://doi.org/10.4047/jap.2013.5.4.434

Abstract

PURPOSE
The aim of the present study was to evaluate the effects of posts with different morphologies on stress distribution in an endodontically treated mandibular premolar by using finite element models (FEMs).
MATERIALS AND METHODS
A mandibular premolar was modeled using the ANSYS software program. Two models were created to represent circular and oval fiber posts in this tooth model. An oblique force of 300 N was applied at an angle of 45degrees to the occlusal plane and oriented toward the buccal side. von Mises stress was measured in three regions each for oval and circular fiber posts.
RESULTS
FEM analysis showed that the von Mises stress of the circular fiber post (426.81 MPa) was greater than that of the oval fiber post (346.34 MPa). The maximum distribution of von Mises stress was in the luting agent in both groups. Additionally, von Mises stresses accumulated in the coronal third of root dentin, close to the post space in both groups.
CONCLUSION
Oval fiber posts are preferable to circular fiber posts in oval-shaped canals given the stress distribution at the post-dentin interface.

Keyword

Post and core technique; Finite element analysis

MeSH Terms

Bicuspid*
Dental Cements
Dental Occlusion
Dentin
Finite Element Analysis*
Post and Core Technique
Tooth
Dental Cements

Figure

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  Fig. 1 Geometry of the model for circular fiber post.

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  Fig. 2 Geometry of the model for oval fiber post.

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  Fig. 3 The meshed model had 262,160 elements and 401,161 nodes for oval fiber post and 263,443 elements and 402,608 nodes for circular fiber post.

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  Fig. 4 Model loading conditions. The boundary condition of the model was a fixed support at the surface of the gingiva.

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  Fig. 5 von Mises stresses measuring from three regions.

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  Fig. 6 (A) von Mises stresses measured along the apical extent of the post (post tip), (B) von Mises stresses measured combination of the core-root dentin interface from the labial to the palatal side, (C) von Mises stresses measured 3 mm above from the b point from the labial to the palatal side.

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  Fig. 7 von Mises stresses for oval fiber post.

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  Fig. 8 von Mises stresses for circular fiber post.

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