**2. Nanobiomaterials**

Nanobiomaterials cover a wide variety of biomaterials including natural and artificial materials, used for various applications in tissue engineering [34–36]. These materials can be classified into two categories, i.e., organic nanobiomaterials and inorganic nanobiomaterials, where the former is characterized by the presence of carbon-containing constituents. Organic–inorganic hybrids are much more effective biomaterials than pure polymers, bioglasses, metals, alloys, and ceramics [37] as they try to combine best properties of constituents following the general concept of composite material. Section 2.1 will review the different types of organic nanobiomaterials, while Section 2.2 will review the different types of inorganic nanobiomaterials.
