Paiva is the No. 112 defensive lineman in the country, per 247Sports composite rankings.
Steelers head coach Mike McCarthy will look to start from scratch as he works to shape Allar into an NFL talent.
The re-signing comes just days after Jacksonville released Wormley from the team.
Dean tallied 590 receiving yards and 11 touchdowns last season with Alcoa High School in Tennessee.
September 5 can't come soon enough.
Allen departs Penn State as the program's all-time leading rusher.