system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why can bones heal but teeth can not?
gpt
Your bones are surrounded with blood veins that can transport the nutrients necessary to repair your bones if they break relatively quickly. Your teeth lack this surrounding vein structure, so to repair holes on the surface they would need to transport the necessary nutrients through bone. Since bone is too rigid to do this at any perceptible pace, the acid damage from the bacteria will outpace any repair that does happen.