Document Type : Full Research Paper


1 Ph.D Student, Biomechanics Department, Faculty of Biomedical Engineering, Amirkabir University of Technology

2 Associate Professor, Biomechanics Department, Faculty of Biomedical Engineering, Amirkabir University of Technology

3 Dentist of Dental Research Center, Tehran University of Medical Sciences

4 M.Sc, Biomechanics Department, Faculty of Biomedical Engineering, Amirkabir University of Technology



Stress analysis is a proper tool in evaluation of vulnerable regions of dental tissues exposed to cyclic loading due to mastication and other physiological functions. In this study, effects of visco-elastic property of dental components on the distribution of stress are investigated in finite element models of upper central tooth prone to dynamic loading. Sensitivity of stress pulse to the visco-elastic property is studied. Results indicate reduction of stress pulse amplitude by elevation of visco-elastic parameter with highest effect in enamel-cementum junction and then in enamel-dentin junction. The visco-elastic property causes smoothening of the stress distribution in dental tissues. Such effect is due to reduction of stress wave amplitude and elevation of the ratio of minimum to maximum stress values. Increased visco-elasticity of components results in elevated phase shift between load and stress waves and higher attenuation of stress wave. This causes slow propagation of attenuated wave leading to lower maximum stress after reflection of stress wave in boundaries and junctions.


Main Subjects

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