Fluid-Dynamic Crestal Sinus Floor Elevation in Atrophic Posterior Maxilla Implant Rehabilitation with Hyaluronic Acid: A Prospective Study

Implant–prosthetic rehabilitation of the posterior edentulous maxilla is challenging due to inadequate bone volume resulting from alveolar ridge resorption and maxillary sinus pneumatization. This study explores the use of hyaluronic acid (HA) as a biomaterial in maxillary sinus elevation, particularly in combination with a fluid dynamic approach, as an alternative to traditional lateral approaches and granular biomaterials. Methods: A prospective study was conducted on 58 patients with posterior maxillary edentulism. Preoperative CBCT scans assessed residual bone height and sinus width. A minimally invasive surgical protocol utilizing a device for fluid-dynamic membrane elevation and injection of 2% cross-linked hyaluronic acid was employed, followed by simultaneous implant placement. Postoperative follow-up included a CBCT scan at 12 months to evaluate new bone height, measured mesially and distally. Implant stability was assessed using resonance frequency analysis at second-stage surgery. Results: A significant increase in bone height was observed at 12 months post-surgery, with an average bone gain of 7.5 mm. All 58 implants achieved primary stability, and no implant failures or signs of peri-implantitis were noted during the follow-up period. Higher bone gain was observed in wider sinuses. Conclusions: The fluid-dynamic transcrestal sinus floor elevation technique combined with hyaluronic acid appears to be a minimally invasive and effective method for achieving significant bone regeneration in the posterior maxilla, facilitating implant–prosthetic rehabilitation with potentially low risks and morbidity. Further large-scale studies are warranted to validate these findings across diverse clinical scenarios.