While eating at a Cracker Barrel Restaurant on Rt 130 in Hamilton NJ, I happened to take a close look at a Dentist's license that was hanging on the wall. It was part of the 'decorations'.
It was a license belonging to a FRANK IRVIN SHAFFER from the state of Pennsylvania on August 5th, 1907.
This information is also recorded in the PA record book V (5), page 2408.
Hope that this posting will be of help to someone.