Dentistry and Dental Materials

This keynote will give an overview of hydrogels use for regenerative dental medicine. Hydrogels are three dimensional networks that have the ability to retain large amounts of water. More than 90% of the body is composed of macromolecules physically or chemically crosslinked in high water content and soluble compounds. Hydrogels have structural similarities with extracellular matrices (ECMs) and versatility that make them the ideal candidates in tissue engineering, drug delivery systems, and  specifi c medical devices. 20 years ago, we designed injectable bioactive suspensions in water of calcium phosphate ceramics for bone and periapical regenerations. Because of leakage of these suspensions, we focused on injectable hydrogels before to set in situ by physical or chemical crosslinking to form 3D scaff olds. Finally, we set up a platform to develop a series of innovative hydrogels for bone, periodontal and endodontic tissue regeneration. We based our strategy on polysaccharides macromolecules because they are renewable materials, that originate from biological sources and generally are biocompatible, non-toxic and biodegradable. We developed a family of silanized and methacrylated macromolecules able to react forming biocompatible hydrogels. Th e silanized polymer are self-setting hydrogel able to covalently crosslink under pH variation, without addition of toxic crosslinking agent. Th e methacrylated polymers allow the in-situ photo crosslinking under standard dentistry lamp using cytocompatible photoinitiators. All these macromolecules could be combine in multicomponent hydrogels, representing a strategy for improving mechanical properties of biomaterials or to tailor particular properties to meet specifi c needs. For mineral scaff olding, we realized composites of calcium phosphates particles or cements with hydrogel, increasing the ductility and creating macroporous scaff old to propose foam bone cements. For endodontic applications we started to explore crushed dentine in high pH hydrogel for local autologous growth factors release and to investigate specifi c galenic formulation for dual molecules delivering. Future perspectives of our strategy are moving towards 3D printing and bio printing techniques. We will use our hydrogel platform to prepare tunable (bio) inks well adapted for specifi c applications in personalized dental medicine.