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 mm(2)) 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.