Effectiveness of Short Implants Versus Long Implants With Sinus Floor Elevation in Patients With Atrophic Posterior Maxilla: A Systematic Review and Meta-Analysis

Abstract

Maxillary sinus floor augmentation (MSFA) has become the standard technique, aiming to increase vertical bone volume to accommodate standard-length implants, typically 10 mm or longer, with a predictable treatment modality. Data have sparked interest in short implants for patients with atrophic jaws. This systematic review and meta-analysis aimed to evaluate the clinical results of short implants compared to long implants with sinus floor elevation. A systematic search of PubMed, Scopus, Web of Science, and the Cochrane Library was conducted from inception to June 2025 to identify randomized controlled trials (RCTs) comparing short implants with long implants and sinus floor elevation in patients with atrophic posterior maxillae. The primary outcome was the mean change in marginal bone loss. Secondary outcomes included rates of implant survival, biological complications, and prosthetic complications. A random-effects model was adopted to pool mean differences (MD) and odds ratios (OR), with 95% confidence intervals (CI). STATA MP version 18 was used for all statistical analyses. Seven RCTs comprising 393 patients and 474 implants were included. Short implants resulted in a significant reduction in marginal bone loss (MD = -0.26 mm, 95% CI: -0.43 to -0.09, p < 0.001; I² = 56.29, p = 0.04) and lower rates of biological complications (OR: 0.39, 95% CI: 0.18 to 0.85, p = 0.02; I² = 0.00, p = 0.92) compared to long implants with sinus floor elevation. Moreover, there was no significant difference between short implants or long implants with sinus floor elevation in terms of survival rates of implants used (OR: 0.96, 95% CI: 0.74 to 1.25, p = 0.76; I2= 0.00, p = 1) or prosthetic complications (OR: 2.18, 95% CI: 0.82 to 5.82, p = 0.12; I2= 25.62, p = 0.44). In conclusion, short implants (<8 mm) may offer an alternative to standard grafting implants. However, further long-term RCTs are needed to draw clear conclusions on survival rates.