Peripheral nerve may regulate the jaw bone resorption after tooth extraction.

A various amount of alveolar ridge resorption is likely to occur after tooth extraction, making it difficult to restore the missing teeth with either endosseous dental implants or prosthodontics approaches. It is commonly thought that the bone resorption is due to the absence of the mechanical stimulation from the occlusal force. However, regulation of the bone mass is a complex homeostatic system involved in hormonal, paracrine/autocrine, mechanical and neuronal nature. Studies have shown that the central and peripheral nervous system play an important role in bone remodeling. The hypothalamus integrates peripheral and central signals, and sends efferent hormonal and neuronal signals in response to stimulation. Numerous neuropeptides detected in the bone marrow have effect on the osteoblast and osteoclast. After tooth extraction, great loss of the axons is observed in the edentulous bone. So we speculate that innervation in the alveolar bone regulates the bone resorption in edentulous area. Methods to promote the nerve regeneration are expected to prevent the jaw bone resorption. The hypothesis also implies that after the placement of the oral implant the abundant nerves in the alveolar bone can increase the bone healing ability and long term survival rate of the implant.