Dr. Lehan earned his BS in Biology from Millsaps College in 1981 and in 1989 he received a Doctorate of Dental Medicine from the University of Mississippi School of Dentistry. After graduation, Dr. Lehan was accepted to a General Dentistry residency with the United States Army at Fort Campbell, KY. He served seven years on active duty with the United States Army practicing in Germany, Massachusetts, and Georgia. Upon leaving active duty in 1996, Dr. Lehan joined the Mississippi Army National Guard. He served as the State Dental Officer from 1999-2015, Commander of the Mississippi Army National Guard Medical Command 2015-2018, deployed multiple times to South America, Central America and Southwest Asia, promoted to Colonel in January 2007 and retired after 38 years of service in March of 2019.
Dr. Lehan also taught at the University of Mississippi Medical Center School of Dentistry as a part-time Clinical Assistant Professor from 2004-2017.