Lateral Sinus Floor Elevation Without Bone Graft: A Single- Center Retrospective Study of 216 Implants with a Mean 4-Year Follow-Up.

Background/objectives: This retrospective study aimed to assess the clinical outcomes of simultaneous implant placement using the lateral sinus floor elevation without bone graft (LSFEWoG) combined with the osseodensification (OD) technique.

Materials and methods: Clinical data from 124 patients who underwent LSFEWoBG combined with the simultaneous implant placement facilitated by the OD approach were retrospectively analyzed. Patients were followed for up to 6 years. Radiographs of the treated sinuses were obtained immediately after the surgery and at the most recent follow-up. Various parameters, including age, gender, smoking, diabetes, implant characteristics (surface modification and apex design), engaging bone height (EBH), number of implants per sinus lift, sinus floor morphology (favorable and unfavorable), elevation height (EH), and bone gain, were recorded and analyzed.

Results: A total of 216 implants were placed using the LSFEWoBG combined with OD approach. Nine membrane perforations (5.9%) were identified out of 152 procedures. The overall implant survival rate was 96.12%, irrespective of perforation or sinus morphology. All implant sites showed significant bone gain of more than 7 mm. Additionally, there was a strong positive correlation between bone gain and EH, with a 1 mm bone gain corresponding to an approximately 0.8 mm increase in EH. Individuals who received single implants experienced similar bone gain compared to those with multiple adjacent implants (P > 0.323). Patients with favorable sinus floor morphology had significantly greater bone gain (P < 0.001) compared to those with unfavorable morphology.

Conclusions: LSFEWoG combined with OD and simultaneous implant placement achieved a high survival rate up to 6 years, with substantial bone gain strongly correlated with sinus morphology. This technique appears effective and consistent, especially in patients with favorable sinus floor anatomy.