Dr. Callahan was born in Pennsylvania and was raised in the Finger Lakes region of New York State. He completed his undergraduate work at S.U.N.Y. at Binghamton. He did a one year residency in general practice at Booth Memorial Hospital in Queens, New York. He then completed his training in Oral and Maxillofacial Surgery at Woodhull Hospital in New York City.
He has been in private practice in the Wilkes Barre/Kingston area since 1984 and is a board certified Oral and Maxillofacial surgeon.