Dr. Langan has been practicing dentistry for the last eleven years as an officer in the US Army Dental Corps. The first seven years were devoted to general dentistry, and the last four years were dedicated to the specialty of endodontics. While serving in the Army, Dr. Langan completed two tours in South Korea and one tour in Germany, in addition to stateside assignments at Fort Campbell, KY, and Fort Gordon, GA. Most recently, he served as Chief of Endodontics for the Fort Eustis, Virginia, Dental Activity from July 2002 to June 2004. While in the Army, Dr. Langan was awarded three Meritorious Service medals and one Army Commendation medal. In addition, he earned the Parachutist Badge and the Expert Field Medical Badge.

Dr. Langan is a 1989 graduate of the University of Pennsylvania where he earned a Bachelor of Applied Science. He attended Tufts University School of Dental Medicine from 1989-1993. Upon graduating from dental school, he then entered onto active duty with the Army. From 1993-1994, Dr. Langan completed the Army's 1-year Advanced Education Program in General Dentistry at Fort Campbell, KY. Dr. Langan received his endodontic specialty training at the US Army Residency Training Program in Endodontics at Fort Gordon, GA, from July 2000 to June 2002. Dr. Langan is an active member of the American Dental Association, and he is a board-eligible member of the American Association of Endodontists.

Dr. Langan is originally from Kinderhook, NY. His father, Daniel J. Langan, Jr., D.D.S., was a general dentist in Kinderhook for twenty years. He and his wife, Sun Ae, reside in Wynantskill, New York.