Biological aspects of bone growth and metabolism in orthodontics

Bone growth and development is central to the practice of orthodontics and dentofacial orthopedics. This chapter reviews in detail the basics of bone biology of facial bones, its growth and development, its adaptive mechanisms to mechanical forces applied along with a note on temporomandibular joint (TMJ) adaptation and how dentofacial orthopedics brings in bone changes. The neural crest is divided into four functional domains, such as: cranial neural crest (CNC), trunk neural crest, vagal and saccral neural crest, and cardiac neural crest. One of the most distinctive features of bone remodeling of both cortical and trabecular bone is the precise coupling of bone resorption and formation. All remodeling activity plays a role in calcium metabolism: the balance of bone resorption and formation at any point in time controls the net balance of ionic calcium released into the extracellular fluid.