Comparison of dynamic mechanical properties of dentin between deciduous and permanent teeth

Purpose: Even though differences between deciduous and permanent dentin have been widely studied, their dynamic mechanical behavior has never been compared. The objective of the present study was to quantify the differences between deciduous and permanent dentin under cyclic mechanical loading, which is similar to masticatory stress. Materials and Methods: Deciduous and permanent teeth, respectively from children (9 ~ 12 years old) and young people (18 ~ 25 years old), were wet-sectioned perpendicular to the longitudinal axis and the central specimens of coronal dentin were evaluated by nanoscopic dynamic mechanical analysis (nanoDMA). Results: The average storage, loss, and complex moduli, as well as the hardness of deciduous dentin were significantly (p Conclusions: Compared with deciduous dentin, permanent dentin exhibits higher stiffness with reduced energy loss during deformation, and therefore superior mechanical characteristics for the mastication process.