In this task, you're given a story (which contains five sentences only). Your task is to find all the characters which are available in the given story.
Q: Sentence1: Tom needed to get braces. Sentence2: He was afraid of them. Sentence3: The dentist assured him everything would be fine. Sentence4: Tom had them on for a while. Sentence5: Once removed he felt it was worth it.
A:
Dentist, Tom