Amazed Dentist

"'Open wider' requested the dentist as he began his examination of the patient.

'Good Grief!' he said startled.

'You've got the biggest cavity I've ever seen -- the biggest cavity I've ever seen.'

'OK Doc!' replied the patient, 'I'm scared enough without you saying something like that twice.'

'I didn't!' said the dentist, 'That was the echo.'"