DeBoer and Moores will join MacTavish behind the bench at the tournament, which begins May 8 in Mannheim, Germany.
DeBoer is finishing his second season with the Panthers. He served twice as an assistant at the world junior championships.
Moores spent nine years as an assistant coach with the Oilers under MacTavish and is a scout for the team.
Canada general manager Mark Messier will start selecting players later this month. The team opens play against Italy.