Tehran University of Medical Sciences Journal of Craniomaxillofacial Research 2345-5489 10 2 2023 10 16 82 85 EN Mojtaba Salehi Department of Oral and Maxillofacial Surgery, Sina Hospital, Tehran University of Medical Sciences, Tehran, Iran; Craniomaxillofacial Research Center, Tehran University of Medical Sciences, Tehran, Iran. Mahboube Hasheminasab Department of Oral and Maxillofacial Surgery, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran; Department of Orthodontics, University of the Pacific, Dugoni School of Dentistry, San Francisco, CA,USA; Craniomaxillofacial Research Center, Tehran University of Medical Sciences, Tehran, Iran. Narges Hajiani Department of Oral and Maxillofacial Surgery, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran; Craniomaxillofacial Research Center, Tehran University of Medical Sciences, Tehran, Iran. 2023 08 30 2023 09 30 Maxillary sinus lift is a common procedure to achieve adequate alveolar bone height in patients  with sinus hyper-pneumatization. Simultaneous implant placement with sinus floor augmentations  is possible when appropriate primary stability could be achieved. In severe atrophic posterior  maxillary ridge, vertical bone height is sometimes less than 4mm, which may hinder simultaneous  implant placements and necessitate two stage procedure. In current study, a novel technique is  described to perform a single stage implant placement with bicortical stability in severe atrophic  maxilla that can shorten the treatment time of an edentulous patient. During the procedure, to  achieve an adequate access a conventional lateral window osteotomy is performed. After elevating  the Schneiderian membrane using conventional instruments, an autologous ramus block is harvested  from the mandible and then the block will be fixed in correct location in the sinus using  screws withb appropriate length to build sufficient stability as superior cortex for simultaneous  implant insertion.  Keywords: Bone graft; Sinus lift; Immediate placement. https://jcr.tums.ac.ir/index.php/jcr/article/view/456 https://jcr.tums.ac.ir/index.php/jcr/article/download/456/381