Adjunctive Photobiomodulation in Sinus-Lift Procedures Em-ploying Two Biomaterials of Different Origins: A Histological and Radiological Evaluation.

(1) Background: Atrophy of the alveolar ridge in the posterior maxilla in case of implant therapy often necessitates a sinus lift procedure, which is associated with complications and prolonged healing. Adjunctive therapies such as photobiomodulation with low-level laser have been proposed to enhance bone regeneration and patient outcomes. (2) Methods: Twenty patients undergoing maxillary sinus floor elevation using the open (lateral window) technique were randomly divided into four groups according to the grafting material used (allograft or xenograft) and the application or omission of diode laser photobiomodulation. After six months of healing, bone core biopsies were obtained during implant placement. The specimens were histologically evaluated, and panoramic radiographs were performed to assess bone gain. (3) Results: LLLT did not produce statistically significant differences but showed consistent positive trends in most evaluated parameters. Histological analysis revealed organized bone formation with minimal inflammation and ongoing mineralization among all groups. Radiographically, all groups demonstrated substantial vertical bone gain, with numerically higher values in LLLT-treated sites. (4) Conclusion: Although the observed effects were not statistically significant, LLLT appeared to modestly enhance osteogenesis and tissue maturation, suggesting its potential as a supportive therapy in sinus lift procedures with different grafting materials