A 4-month-old infant in Maryland was the first person to have had teeth form in his brain because of a very rare type of brain tumor, according to a new report of the case. The boy is doing well now that his tumor has been removed, and doctors say that this is a very unique and rare case. At first the doctors thought that something might be wrong because the head of the child appeared to be growing faster than is typical for children who are his age. A scan of his brain revealed a tumor containing structures that looked very similar to teeth normally present in the lower jaw. The child underwent brain surgery in which the tumor was removed, during which doctors found that the tumor contained several fully formed teeth, according to the report.