To compare clinical and radiographic success rates of a modified primary root canal filling ( ingredients : zinc oxide-eugenol , iodoform and calcium hydroxide , MPRCF ) vs. zinc oxide-eugenol cement ( ZOE ) and calcium hydroxide/iodoform paste ( Vitapex ) in pulpectomized primary molars at the end of 6 and 12 months , and to evaluate the degradation of materials in the root canals and in apical area .