To identify a person from his or her teeth, a forensic dentist must have a dental record or records from the deceased person's dentist. In the case of an incident involving multiple deaths, forensic dentists receive a list of possible individuals and compare available records with the teeth and find a match. Examining the teeth of an intact corpse often requires working in a morgue to expose the jaws surgically. Even if only a few teeth are available, a forensic dentist can still make a positive identification. The best comparisons come from X-rays , but even if those aren't available, notations on the tooth chart can tell the dentist if the teeth are the same.