Deproteinized bovine bone and freeze-dried bone allograft in sinus floor augmentation: A randomized controlled trial

The aim of this study was to investigate the effects of deproteinized bovine bone (DBB, Bio-Oss®) and freeze-dried bone allograft (FDBA, SureOss®) on bone healing during maxillary sinus floor augmentation (MSFA) using histology, immunohistochemistry, and gene expressions of the marker genes including Runx2, Opn, Ocn, Col1a1, Rankl, and Tnf-α.

Fourteen participants who required two-stage maxillary sinus augmentation were randomly assigned to DBB and FDBA bone grafting groups. Six months after the sinus augmentation procedure, bone samples were collected before implant placement with a trephine bur. Gene expression of Runx2, Opn, Ocn, Col1a1, Rankl, and Tnf-α of the bone samples was assessed by real-time polymerase chain reaction as a primary outcome. Histological analysis of H&E-stained sections, immunohistochemistry for OPN quantification, and CBCT-based bone tissue examination were performed to investigate the bone healing effects of DBB and FDBA substitutes.

The FDBA treated group showed higher gene expression when compared with the DBB treated group in Opn (2.83 ± 1.23 vs. 1.40 ± 0.69; p = 0.04), Runx2 (1.49 ± 0.44 vs. 0.67 ± 0.14; p = 0.01), and Rankl (2.34 ± 0.85 vs. 0.69 ± 0.39; p = 0.03). In the DBB treated group a downregulated expression was found of Ocn relative to maxillary edentulous bone (1.18 ± 0.40 vs. 2.51 ± 0.78; p = 0.02).

Two-stage maxillary sinus augmentation with FDBA upregulated specific bone remodeling genes when compared to DBB. The outcome of gene expression matched with the ones for OPN immunoreactivity, being higher in the FDBA group. FDBA had an expression pattern similar to native bone and showed stronger expression of bone forming related-genes suggesting it may be clinically preferable over DBB. This clinical trial was not registered prior to participant recruitment and randomization (clinical registration number TCTR20221217002).