Zanna also had nine rebounds for the Panthers (16-1, 4-0 ACC), who won the battle of the boards 38-18 and shot 56.9 percent from the field.
James Robinson pitched in with 16 points and five assists. Cameron Wright scored 14.
Pitt trailed 35-32 at halftime but scored 49 points in the second half to grab their sixth consecutive win.
Trae Golden led Georgia Tech (10-7, 1-3) with 22 points and Marcus Georges-Hunt scored 13. Daniel Miller scored 12 from the center position and also blocked five shots. Georgia Tech has lost three of its last four games.