A man went to the dentist to treat a terrible toothache he had.
The dentist sat him down and said: “Open wide.”
After a moment’s pause, the dentist gasped and said: “Good grief! You’ve got the biggest cavity I’ve ever seen… the biggest cavity I’ve ever seen.”
“Okay Doc!” replied the patient in annoyance. “I’m scared enough without you saying something like that twice.”
“I didn’t!” answered the dentist. “That was the echo.”