How does a baby root canal work?

Not given to babies.

ANOTHER ANSWER:

Sometimes a procedure called a 'pulpotomy' is performed on baby teeth. It is essentially the same as a root canal procedure on an adult tooth. The tooth is numbed with local anesthetic, the tooth is opened with a dental drill, the nerve and the infection is removed, and filling material is used to restore the tooth. It will typically preserve the baby tooth until the tooth is lost in the normal process of growth or 'exfoliation' where baby teeth are lost to make room for the permanent teeth.