Abstract: Objective To explore the clinical effect of immediate implantation combined with osteotome sinus floor elevation (OSFE) without bone grafting at the posterior maxilla in the elderly patients with insufficient residual bone height (RBH < 5 mm) after tooth extraction. Methods A retrospective study was conducted on 40 elderly patients who underwent immediate implantation combined with OSFE at the posterior maxilla at Department of Implantology, Nantong Stomatological Hospital from June 2019 to June 2021, with a total of 40 implants. The patients were divided into no-bone-grafting group (20 implants) and bone-grafting group (20 implants). The implant survival rate, implant stability quotient (ISQ) immediately after surgery and 6 months after surgery, and the changes in RBH and bone volume at the implant neck 6, 12, and 24 months after surgery were compared between the two groups. Results Among the 40 implants, 39 were successful (97.5%), including 20 in the no-bone-grafting group (100.0%) and 19 in the bone-grafting group (95.0%), with no significant difference between the two groups (P>0.05). There was no significant difference in the ISQ value immediately after surgery and 6 months after surgery between the two groups (P>0.05). Both groups achieved effective sinus floor elevation. The bone height increase in the bone-grafting group was significantly greater than that in the no-bone-grafting group 6, 12, and 24 months after surgery (P<0.05). There was no significant difference in the bone volume at the implant neck 6, 12, and 24 months after surgery between the two groups (P>0.05). Conclusions For the elderly patients, immediate implantation combined with OSFE without bone graft has good clinical effect and meets the needs of elderly patients.

Key words: osteotome sinus floor elevation, immediate implantation, bone graft, short implant