Is it possible for a fallen tooth to re-root itself back to its original state?

Fallen tooth ?: Re-root ? These are terms I am unfamiliar with. If you are asking if a tooth that is healthy that has been accidentally knocked out can be re-implanted and have it adhere to your bone, the answer is yes in most instances if it is done quickly. If you are asking if a periodontally diseased tooth can be re-implanted successfully, the answer is absolutely no.

Agree: Agree with previous answer. If a traumatically displaced tooth is reinserted promptly, it can re-attach. If loss due to periodontal problems, no.