Both appeared in four preseason games with the Heat. Dozier averaged 1.5 points and 3.3 rebounds in nearly 11 minutes per game, and Gladness averaged 1.3 points and 2.3 rebounds in about eight minutes per outing.
The reigning NBA champions announced the moves on Sunday, an off day from practice. Dozier was Miami's second-round draft pick in 2009. Gladness played in 26 NBA games last season, 18 of them with Golden State and eight with Miami.
The Heat roster now stands at 18 players. Teams must get down to no more than 15 to set their initial regular-season roster.