Sinus augmentation using rh BMP ‐2/ ACS in a mini‐pig model: Influence of an adjunctive ceramic bone biomaterial

Background Recombinant human bone morphogenetic protein‐2 in an absorbable collagen sponge carrier (rh BMP ‐2/ ACS ) has been shown to support significant bone formation when used to augment the maxillary sinus for implant dentistry. Nevertheless, bone biomaterials have been suggested to extend rh BMP ‐2/ ACS with limited support of the merits of such approaches. Objectives To evaluate local bone formation/dental implant osseointegration following implantation of rh BMP ‐2/ ACS combined with a ceramic bone biomaterial using a mini‐pig sinus augmentation model. Methods Twelve adult Göttingen mini‐pigs received rh BMP ‐2/ ACS (rh BMP ‐2 adjusted to 0.43 mg/cc) alone or combined with an off‐the‐shelf biphasic ceramic (15%/85% HA /ß‐ TCP ) biomaterial at 3:1, 1:1 and 1:3 ratios randomized to contra‐lateral maxillary sinus sites yielding rh BMP ‐2/ ACS fractions of 100%, 75%, 50% and 25%, respectively. A 4‐cc implant volume was used for all sites. Two threaded dental implants (ø4.0 × 11.5 mm) were placed at each site. The animals were euthanized at 8 weeks for histologic analysis. Results Surgical execution and healing were generally uneventful, infraorbital local swelling was observed in all animals until suture removal. rh BMP ‐2/ ACS combined with the ceramic biomaterial did not significantly enhance local bone formation (range 9.0 ± 1.5 to 9.7 ± 2.1 mm) compared with rh BMP ‐2/ ACS alone (8.6 ± 1.1 mm; p  >   0.05). Variations in rh BMP ‐2/ ACS to ceramic matrix ratios yielding rh BMP ‐2 doses approximating 0.4, 0.9, 1.3 and 1.7 mg/sinus did not appreciably influence bone formation/osseointegration. Conclusions Whereas rh BMP ‐2/ ACS supports significant bone formation/osseointegration in the mini‐pig sinus augmentation model and thus appears an effective alternative for sinus augmentation procedures, adding a ceramic biomaterial to rh BMP ‐2/ ACS does not produce meaningful biological advantages.