Yes. If the cavity is deep into the tooth and reaches the nerve just doing a filling will cause more harm than good. Your child could begin to experience pain and swelling. A root canal on a baby tooth is called a pulpotomy. It is much simpler, quicker, and less expensive than a root canal on an adult tooth. During a pulpotomy, the infected nerve and tissue inside of the tooth is removed. The stainless steel cap protects the restored tooth from breaking. If the tooth is removed instead, a space maintainer needs to be worn to leave room for the permanent tooth that will grow in later.