Nanotechnology and its applications to medicine, known as nanomedicine, involve a wide use of nanomaterials to stimulate and guide the regenerative properties of cells. In particular, tissue regeneration can be promoted by enabling a controlled release of therapeutic agents, which can be done using nanoparticles. In this review article, the fundamentals of tissue regeneration are discussed, focusing on epithelial tissue, to demonstrate the importance of delivering therapeutic agents in an efficient, sustained and localized manner. Then, the methods for synthesizing metallic and polymeric nanoparticles are described. While polymeric nanoparticles can be loaded with an agent during synthesis, metallic nanoparticles must first be synthesized to later interact with therapeutic agents. This interaction can be fine-tuned by functionalizing metallic nanoparticles with organic molecules, which results in a more controlled attachment.This review highlights the importance of choosing the appropriate method of synthesis and functionalization, which must be designed considering both the type of tissue to regenerate and the nature of the agent to be transported.