'Chairman. Consensus Group. Department of Endodontics. School of Dentistry. University of North Carolina. Chapel Hill. North Carolina 27514. USA; 2Co-chairman, Consensus Group. NIOM. Forskningsveien I. 0371 Oslo 3. Norway; 3Session Chairman. Georgetown University, School of Dentistry. 3900 Reservoir Road, NW. Washington. DC 20007, USA; 4Session Chairman, University ofMichigan. School of Dentistry. Ann Arbor, Michigan 48109. USA; 5Session Chairman. Columbia University, School of Dentistry. Department of Endodontics. 630 West 168th Street. New York. New York 10032. USA; 6Session Chairman. University of Toronto. Faculty of Dentistry, 124 Edward Street, Toronto. Ontario. Canada M5G IG6; and "Session Chairman University of Pennsylvania, School of Dental Medicine, 4001 Spruce Street, Philadelphia. Pennsylvania 19104, USA •