The aim of this study is to determine whether the technique of  interpositional grafting of the posterior mandible without the use of fixation device (using bone blocks alone) is superior to the conventional interpositional grafting with fixation (plates and screws). This study was conducted on 15 patients in which 16 mandibular segments were augmented, segments were randomly divided into 2 groups, control receiving interpositional segmental grafting of the posterior mandible with fixation and intervention group receiving same procedure but without grafting and fixed via chin bone blocks. Results revealed better overall clinical and radiographic results toward the intervention group in terms of graft resorption and application but was statistically non-significant, while the histological evaluation yielded to the postulation that no microscopic difference between both techniques in terms of the resultant bone. Thus concluding that interpositional grafting technique without the use of a fixation device was  a reliable technique for vertical ridge augmentation of the atrophied posterior mandibular ridges with promising rates of success, reduced complications and reduced bone resorption values compared to conventional interpositional grafting with fixation protocol.