Biphasic calcium phosphate and polymer-coated bovine bone matrix for sinus grafting in an animal model

Autogenous bone grafting requires a donor site and may lose substantial volume during remodeling. Several bone replacement materials (BRMs) are under development to overcome these limitations, especially for indications for minimally intervention surgeries. The objective of our study was to assess the potential of an equine collagen cone reinforced with biphasic calcium phosphate (CC-BCP) particles and deproteinized bovine bone matrix (BBM) coated with polylactic acid, and poly-ε-caprolactone copolymer (BBM-PCC) and then to compare the outcomes with a deproteinized BBM and an equine CC without a filler in a sheep sinus grafting model in the Elleven female sheep were selected. Two experimental sites on each side of the animals were prepared using an extraoral approach for maxillary sinus wall. The four treatments were performed in each animal through a standardized 10-mm access window. While the BBM access was covered with a collagen membrane, all other sites were closed with an equine collagen membrane. All animals were euthanized after 16 weeks. New bone (NB), residual graft particles, and connective tissue were measured in undemineralized resin-embedded sections. As a result, one sheep did not survive the surgery. All sites in the remaining 10 sheep healed uneventfully. All CC and BBM-PCC grafts resorbed and failed to augment the sinuses. BBM and CC-BCP, in contrast, showed some histologic evidence of NB and surgical site augmentation. The NB fraction in the latter two groups accounted for 10 ± 9 and 4 ± 5%, respectively (p > 0.05). In conclusion, BBM-PCC and collagen cone performed poorly for sinus floor augmentation, while deproteinised BBM and reinforced collagen cone demonstrated comparable outcomes.