Jose Mourinho's side are on course to win the competition for the 10th time.
Substitute Dybala put Roma ahead in the 64th minute, the former Juventus man sent a powerful shot from a tight angle inside the far post after replacing midfielder Lorenzo Pellegrini at halftime.
Earlier on Thursday, Fiorentina advanced to the quarterfinals with a 1-0 win over Sampdoria.
Serie A leaders Napoli host bottom-placed Cremonese on Tuesday. Atalanta, Lazio and Juventus play their last-16 ties next Thursday.