Caporusso signed a two-year entry level contract, while Silfverberg signed a three-year entry level deal.
Caporusso, from Toronto, was a member of the University of Michigan Wolverines team that reached the NCAA championship game this April.
The five-foot-10, 180-pound centre played 41 games for the Wolverines this season, scoring 11 times and adding 20 assists. In four years with Michigan, he had 68 goals and 76 assists while registering 96 penalty minutes in 160 games. He ranked second in team scoring in each of his sophomore, junior and senior seasons.
Silfverberg, from Gavle, Sweden, spent the last three seasons with Brynas of the Swedish Elite League. In 2010-11, the 20-year-old set career highs with 18 goals and 16 assists in 53 games.
The six-foot-one, 187-pound centre led Brynas in goals and was third on the team in scoring.
Caporusso was drafted by Ottawa in the third round of the 2007 NHL Entry Draft, 90th overall. Silfverberg was the Senators' first of two second-round picks -- 39th overall -- in 2009.
Silfverberg played for Sweden at the 2011 world championship and the last three junior hockey world championships, winning a silver medal in 2009 and a bronze in 2010.