Army Col. Richard J. McConnell, 43, a dentist and administrative officer, died March 21 in Mannheim, Germany, after apparently suffering a heart attack.

He had been commander of dental services of the 768th Medical Detachment hospital there for the last seven months.

Before that, Col. McConnell had served for two years with the Army Medical Historical Unit at Ft. Detrick, Md. In 1973 and 1974, he was management and studies officer in the office of the Army Surgeon General in Washington.

He was deputy commander of the Army Institute of Dental Research at Walter Reed Medical Center in 1971 and 1972. During his assignments here, the family lived in Silver Spring.

Born in Hallock, Minn., Col. McConnell attended the University of North Dakota and graduated in 1957 from the University of Minnesota Dental School.

He then entered the Army as a dentist, serving in Alaska and at Ft. Benning, Ga. He was in Vietnam in 1967 and 1968.

Col. McConnell studies with the Army hospital administrative program and taught at the Academy of Health Sciences at Ft. Sam Houston, Tex., before his assignment here. He received a master's degree in education from George Washington University in 1974.

He was a member of the American Dental Association and the American Hospital Association and was a fellow of the American College of Dentists.

He is survived by his wife, Shirley Ann, and two sons, Richard and Thomas, now living in San Antonio, Tex.; another son, James, of Denton, Tex., and his mother, Mrs. C.B. McConnell, and a brother, Dennis, both of Sequim, Wash.