Human teeth are in fact the only part of the body that heal or repairthemselves.
Repairing means either re-growing what was lost or replacing it with scar tissue and the human teeth do not undergo this. They are not made of live tissue and are coated in enamel, which can’t spontaneously regenerate.
The human brain for example will not regrow damaged brain cells but can repair an area by laying down other scar-type tissue.