Colonel Fulsaas entered the active-duty Air Force on 6 July 1990 as a General Practice Resident at Bolling Air Force Base, Washington DC. In August 1991 he was assigned as a general dental officer at Lajes Field Dental Clinic, Azores Portugal. From November 1992 until June 1995, Colonel Fulsaas was assigned to the 52nd Fighter Wing at Spangdahlem Air Base, Germany as a staff dentist. Izmir Turkey was his next assignment from June 1995 until September 1996. He then proceeded to Keesler Air Force Base, Mississippi to await training in the 2-year Comprehensive Dentistry Program, from 1 July 1997 to 30 June 1999.