On the Use of a Sticky Bone Substitute in the Presence of a Ruptured Sinus Membrane During Sinus Elevation Procedures: An Experimental Rabbit Study

Purpose: To assess the efficacy and safety of a sticky dual-phase porcine-derived bone substitute compared to a similar dual-phase xenogeneic non-adhesive bone graft in the presence of induced perforations of the sinus membrane during sinus elevation procedures in a split-mouth rabbit model. Materials and Methods: Bilateral sinus floor elevations were performed in 12 rabbits. The sinus mucosa was intentionally perforated using a blade on both sides and randomly filled with either a corticocancellous bone embedded in a 20% thermosensitive gel (sticky bone test group [GTO]) or a corticocancellous bone and 10% collagen (control group [mp3]). Healing progress was evaluated after 2 and 10 weeks in 12 animals (6 in each group) with CBCT imaging, microcomputed tomography (microCT), and histologic assessments. Results: One animal of the 2-week group died but was substituted. No other complications were observed. At the 2-week time point, CBCTs revealed that biomaterial particles were observed in the vicinity of the sinus membrane in two out of six sinuses of each group but never dispersed into the sinus. MicroCT and histology consistently revealed few granules beyond the elevated region. Histologically, five sinuses in the mp3 group and two sinuses in the GTO group exhibited granules outside the elevated region but in the vicinity of the perforations. In the 10-week groups, the number of affected sinuses decreased to one in the mp3 group and two in the GTO group. Throughout all observations, the graft granules consistently resided proximate to the elevated region. MicroCT demonstrated a reduction in the volume of the elevated region by approximately 12% after 2 weeks and 50% to 54% after 10 weeks. Conclusions: The use of both sticky and non–sticky bone substitutes was observed to prevent a substantial amount of particles from extruding through an induced perforation of the sinus membrane. This suggests that it could be possible to use a sticky bone substitute as an alternative to a barrier membrane to avoid the extrusion of bone granules in the presence of accidental perforation of the sinus membrane in clinical practice. After 10 weeks of healing, the volume of the elevated region decreased by approximately 50%, possibly due to biomaterial resorption and loss through the surgically created perforation.