In vivo graft performance of an improved bone substitute composed of poor crystalline hydroxyapatite based biphasic calcium phosphate

Abstract

The ability to promote new bone formation of poor crystalline hydroxyapatite (PC-HA) based biphasic calcium phosphate (BCP) bone substitutes were investigated. Various ratios of porous PC-HA/β-TCP (70/30, 60/40, and 0/100) grafts were fabricated. SEM and XRD measurements were performed to study the morphology and crystalline structure. Cylindrical artificial bone defects (3×6 mm²) were produced in alveolar bone at premolars extraction site and then filled with sterilized bone grafts. Commercial MBCP^® and unfilled empty defect served as control groups. At 8 weeks postoperation, samples were harvested from each artificial defect site for histological analysis. New bone formation of all the PC-HA/β-TCP groups was significantly greater than that of the empty control group (p<0.05), but without statistical difference from that of MBCP^® group. The degree of uniformity of new bone formation within defect region for PC-HA/β-TCP (60/40) was higher than that for MBCP^®. The PC-HA/β-TCP grafts showed enhanced bone regenerations with a more even dispersion of new bone formation than the other materials without causing inflammation, suggesting that these materials may be an alternative choice for bone void fillers in dental applications.