Histologic and ultrastructural analysis of regenerated bone in maxillary sinus augmentation using a porcine bone-derived biomaterial.

Background: The purpose of the present study was the histologic and ultrastructural evaluation of a biomaterial composed of cortical pig bone in the form of granules. Methods: After maxillary sinus augmentation using this biomaterial, 10 specimens were retrieved after 5 months in 10 patients using this biomaterial. The specimens were processed to be observed under light microscopy (LM) and transmission electron microscopy (TEM). Histomorphometric measurementswere presented bymeans – standard deviations. Results: LM showed that most of the particles were surrounded by newly formed bone. In some areas, the osteoid matrix was present; however, mainly compact bone was present at the interface. There was no evidence of an acute inflammatory infiltrate. The newly formed bone was 36% – 2.8% and marrow spaces were 38% – 1.6%, whereas residual graftedmaterial was 31% – 1.6%. Under TEM, all phases of bone formation (osteoid matrix, woven, and lamellar bone) were observed in proximity with the biomaterial particles. The bonebiomaterial interface showed a close contact between the porcine bone particles and the surrounding bone that had mainly features of mature bone with numerous osteocytes. A lamina limitans was sometimes present at this interface. Conclusions: According to our knowledge, this is the first study presenting data on TEMof a porcine bone–derived biomaterial used in sinus augmentation procedures in humans. Our findings show that this is a biocompatible biomaterial that can be used formaxillary sinus augmentation procedureswithout interferingwith the normal reparative bone processes.