Mandibular Diseases

* Full thickness Buccal bone lid approach is well known and well reported technique with a superiority on preserving bone volume and better bone healing especially when done using piezoelectrical devices when compared to conventional technique for management of mandibular pathosis, however periosteum disturbance have a negative role regarding vascularity and bone healing, by comparing the split thickness VS full thickness flap design with buccal bone lid approach, this study will highlight if the periosteum preserved attached to the lid improve the healing on mandibular bony pathosis. * Aim of the study: determine the effect of split thickness flap vs full thickness flap using a guided bone lid in hard mandibular pathosis in term of bone healing.