Bioinspired inverse enamel-like columnar composites reproducing the mechanical properties and tribological performance of human enamel

The development of high-performance dental materials that mimic human enamel is urgently required for clinical applications, but remains a key challenge. Herein, we present a biomimetic design strategy for creating inverse enamel-like columnar composites that replicate the mechanical properties and tribological performance of the natural enamel. Inverse to the enamel consisting of hard rods and surrounding relatively soft inter-rod, the composites are assembled from a cellular-structured ceramic scaffold and resin columns. This architecture helps to avoid dramatic stiffness and hardness decreases due to the presence of flexible substances and provides an elegant combination of mechanical properties that strikingly resemble that of natural enamel. Consequently, the inverse enamel-like columnar composites have encouraging tribological performance characterized by an enamel-matched coefficient of friction and wear rate, as well as low abrasive potential to opposing natural teeth, demonstrating great promise for next-generation dental restorations/replacements and other applications. More importantly, the proposed design strategy can be extended to other biological prototypes, thus facilitating the development of various high-performance functional materials.