Bone is a highly vascularized organ that not only plays multiple roles in supporting the body and organs but also endows the microstructure, enabling distinct cell lineages to reciprocally interact. Recent studies have uncovered relevant roles of the bone vasculature in bone patterning, morphogenesis, homeostasis, and pathological bone destruction, including osteoporosis and tumor metastasis. This review provides an overview of current topics in the interactive molecular events between endothelial cells and bone cells during bone ontogeny and discusses the future direction of this research area to find novel ways to treat bone diseases.

Pregnancy- and lactation-associated osteoporosis (PLO) is receiving increasing attention. During pregnancy and lactation, bone metabolism is dramatically changed to supply minerals to the fetus and infant, which is a major cause of PLO. Weaning of lactation is clinically a primary choice to treat lactation-induced osteoporosis since breastfeeding is a key regulator of the pathophysiology during lactation. However, breastfeeding is beneficial to the physical and mental development of infants. We also discuss the beneficial effects of breastfeeding on the oral and maxillofacial development of infants. Pharmacological treatment of PLO is also discussed. This review also discusses how dynamic regulatory changes in bone metabolism during pregnancy and lactation affect homeostasis of the temporomandibular joint (TMJ) and alveolar bone in mothers, from the perspectives of TMJ diseases and orthodontic treatment.