Improvements have been made in regenerative medicine, due to the development of 
tissue engineering and cellular therapy. Bone regeneration is an ambitious 
project, leading to many applications involving skull, maxillofacial, and 
orthopaedic surgery. Scaffolds, stem cells, and signals support bone tissue 
engineering. The scaffold physical and chemical properties promote cell 
invasion, guide their differentiation, and enable signal transmission. Scaffold 
may be inorganic or organic. Their conception was improved by the use of new 
techniques: self-assembled nanofibres, electrospinning, solution-phase 
separation, micropatterned hydrogels, bioprinting, and rapid prototyping. 
Cellular biology processes allow us to choose between embryonic stem cells or 
adult stem cells for regenerative medicine. Finally, communication between cells 
and their environment is essential; they use various signals to do so. The study 
of signals and their transmission led to the discovery and the use of Bone 
Morphogenetic Protein (BMP). The development of cellular therapy led to the 
emergence of a specific field: gene therapy. It relies on viral vectors, which 
include: retroviruses, adenoviruses and adeno-associated vectors (AAV). 
Non-viral vectors include plasmids and lipoplex. Some BMP genes have 
successfully been transfected. The ability to control transfected cells and the 
capacity to combine and transfect many genes involved in osseous healing will 
improve gene therapy.