Three-dimensional finite element modeling from CT images of tooth and its validation

Division of Biomaterials, Kyushu Dental College, 2-6-1 Manazuru, Kokurakita, Kitakyushu 803-8580, Japan.
Dental Materials Journal (Impact Factor: 0.97). 04/2009; 28(2):219-26. DOI: 10.4012/dmj.28.219
Source: PubMed


The aim of this study was to develop a three-dimensional (3D) finite element (FE) model of a sound extracted human second premolar from micro-CT data using commercially available software tools. A detailed 3D FE model of the tooth could be constructed and was experimentally validated by comparing strains calculated in the FE model with strain gauge measurement of the tooth under loading. The regression coefficient and its standard error in the regression analysis between strains calculated by the FE model and measured with strain gauge measurement were 0.82 and 0.06, respectively, and the correlation coefficient was found to be highly significant. These results suggested that an FE model reconstructed from micro-CT data could be used as a valid model to estimate the actual strains with acceptable accuracy.

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Available from: Kiyoshi Tajima
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    • "However, it is difficult to systemize the data, as tooth dimensions and experimental conditions are not usually included. From a theoretical standpoint, many studies have been made of stress distributions in loaded teeth using conventional finite element modeling (FEM) codes [24] [25] [26] [27] [28] [29] [30] [31] [32], but these can say virtually nothing about how stable fractures evolve. They certainly cannot account for any stages of crack arrest in the enamel and subsequent penetration into the dentin interior [13]. "
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    • "Dessa forma a disponibilidade de modelos da mandíbula, tanto dentada quanto desdentada, pode facilitar diversas pesquisas na área, além de favorecer possíveis análises comparativas que utilizam o mesmo modelo geométrico. Os exames de micro tomografias, devido à sua alta precisão, seriam teoricamente o melhor método para obtenç ão de modelos anatômicos geometricamente precisos [7] [8] [9] [10], entretanto, devido ao alto custo, alta exposiç ão à radiaç ão e limitaç ão quanto ao tamanho da zona analisada, esses são contraindicados para utilizaç ão em seres humanos vivos. Aumento na dose de radiaç ão está diretamente relacionado à qualidade da imagem obtida, com melhora no contraste e diminuiç ão de artefatos [11] [12] e micro tomógrafos utilizam níveis de radiaç ão muito maiores que o aceitável para aplicaç ão em pacientes vivos. "
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    • "Twodimensional or three-dimensional approaches have been used for modeling purposes [6]. Two-dimensional models are criticized as they result in oversimplified geometries of complex structures that in turn may compromise the reliability of predicting the mechanical behavior of the object [7] [14] [15]. "
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