In this manuscript there are presented two cases, both with mandibular reconstruction with autograft harvested from the iliac crest, performed more than 40 years ago, but with different bone defect etiology, i.e., mandibular dysplasia and mandibular fracture, both having currently extensive tooth loss in the mandible, being in need for prosthetic rehabilitation. These cases confirm that reconstructive surgery of mandibular bone defects with autograft from iliac crest has a satisfactory long-term outcome, providing acceptable conditions for prosthetic rehabilitation. Bone resorption in the grafted area seems to be related to the etiology of bone defect, and influenced by preservation of dental occlusion and masticatory function. Reconstructive surgery made decades ago has sequelae that increase the difficulty of prosthetic treatment of edentulous patient, that need to be proper evaluated and included in the treatment plan, in an individualized approach, in order to obtain an acceptable functional outcome.