This paper reports on a segmental osteotomy procedure with an interpositional graft in the posterior maxillary region with 9 years of follow-up.
The techniques used to overcome a lack of alveolar bone height rely on the placement supplemented by various vertical guided bone regeneration (GBR) procedures [4, 5] and the use of alveolar distraction osteogenesis , titanium mesh , or onlay bone graft . Gains in ridge height of between 3.6 and 9.2 mm depending on the materials used have been reported, and these were associated with 5-year implant survival rates of 97 to 100%, depending on the method employed . On the other hand, it has also been reported the number of complications (e.g., flap dehiscence, barrier exposure) and failures of the augmentation procedure (e.g. infection, graft bone necrosis) [3,4,5,6,7,8]. Additionally, the biomaterials used as substitutes for the bone require a longer healing time than autologous bone because the substitutes in general are not osteoinductive .
Although a certain amount of slow appositional bone growth from the bony walls into the defect is observed, this growth depends on the growth of new blood vessels between each particle. In the alveolar crest, it spontaneously stops at a distance of few millimeters above the defect bone wall. The more distant particles instead heal within fibrous tissue to form a scar. This is expected to have a negative effect on the long-term survival of the restoration .
The use of short implants is another possibility when alveolar bone height is inadequate for regular implants. The use of such implants can reduce treatment time, cost, and postoperative morbidity compared to bone augmentation procedures. The first EAO consensus conference (2006) had defined short implants as a device with a design intrabony length of 8 mm or less  and had demonstrated high success rates and predictable clinical outcomes for placement of short implants [12,13,14], but there were still controversies regarding the long-term consequences of peri-implant bone loss around short implants and its impact on the long-term implant success rate at that time.
In this case, the alveolar ridge was Seibert class II, and septa and a thickened sinus membrane were evident within the maxillary sinus. Sinus floor elevation was limited because of the condition of the floor morphology, the presence of septa, and the thickness of sinus floor membrane [22, 23]. Considering these issues, we selected the interpositional bone graft technique using autologous bone in preference to short implants or the use of a biomaterial.
The inlay bone graft technique, first described by Schettler and Holtermann in 1977  which presented the reconstruction of a severely atrophic edentulous mandible, has great potential for bone graft incorporation. The technique is relatively simple and provides satisfactory results both in terms of surgical success and predictability [15,16,17,18,19]. The technique is predicable because the four walls of the graft are in contact with live tissue, increasing vascularization and reducing resorption . A box-style gap opens between the segments, which borders on an open bone marrow cavity on two sides. This space offers excellent conditions for vascularization of the graft and bone healing. Thus, a temporary prosthesis can be used in the early postoperative period. Since that first report, several reports on research outcomes, technological progress, and the good results obtained with this technique have been published. This technique is now regarded as a good way to correct vertical deficiencies prior to placement of dental implants [15,16,17,18,19].
On the other hand, alveolar augmentation depends on the operator’s experience and is technically sensitive . The most common difficulty is how to manage the soft tissues to preserve the blood supply to the cranial segment; releasing incisions make tension-free closure possible so that the segment does not move palatally.
Nevertheless, in this case, the procedure was carried out successfully, and two regular implants were successfully placed in the alveolar ridge after its enhancement with an autologous bone graft. Those implants survived over 9 years of follow-up.