Nerve killing of milk teeth usually does not affect the nerve of the new tooth. Nerve killing is a root canal procedure that usually does not affect the growth of the new tooth because the nerve of the baby tooth and the embryonic nerve of the new tooth are two separate systems that do not interfere with each other under normal circumstances. Killing the nerves of the milk teeth usually only affects the texture of the milk teeth, while the new teeth have their own independent nerve system after growth. Therefore, killing the nerve of milk teeth will not affect the new teeth. If the decay of the milk tooth is very serious, before killing the nerve, the infection at the root of the milk tooth has spread to the surrounding area, affecting the new tooth germ below, in which case the new tooth may be affected and the new tooth may decay. Once periodontal disease is present in the milk teeth, parents are advised to bring their children to the clinic in time for active treatment under the doctor’s guidance, so as not to delay the condition and affect the eruption of the new teeth.