Dr. Debelian completed his specialisation in Endodontics at the University of Pennsylvania, USA, in 1991 and received the Louis I. Grossman Student Award in Endodontics. He taught as a clinical instructor and associate professor in the post-doctoral endodontic programme at the Department of Endodontics, University of Oslo, Norway, from 1991 to 2001 and from 2006 to 2010.

He concluded his PhD studies at the University of Oslo in 1997 on endodontic microbiology, which earned him two scientific awards in 1997, from the European Society of Endodontology (ESE) and the Norwegian Dental Association. He is an adjunct visiting professor in the postgraduate programme in endodontics at the University of Pennsylvania in Philadelphia, USA.

Dr. Debelian maintains a private practice limited to Endodontics and is the director of the endodontic microscopy centre, EndoInn. He has authored five book chapters and one book in Endodontics, and has written more than 60 scientific and clinical papers. He is currently a member of the scientific advisory panel for the Journal of Endodontics and the International Endodontic Journal, director of the Oslo Endodontic Study Club, and past vice-president of the Norwegian Endodontic Society.

Dr. Debelian lectures nationally and internationally on a range of biological and clinical topics in endodontics. He is also involved in hands-on courses on topics including NiTi instrument technologies and operative dental microscopy in conventional, retreatment and surgical endodontics.