there was a study in 2003 that showed it to be effective for frontal baldness as well. i'm not sure if it's as effective as it is on the crown, however
and i believe the only way to have "new" hair growth that doesn't require life long treatment is with hair grafts or flap surgery because its from a dht resistant area of the scalp. if you stop taking the dht inhibitors, your dht will come back and dht sensitive hair follicles will atrophy and fall out