Macroscopical, histological, and morphometric studies of porous bone-replacement materials in minipigs 8 months after implantation

ObjectiveThe aim of this investigation was to test the induction of bone formation and biodegradation of different biomaterials based on calcium phosphate (CaP). Up to now, hydroxyapatite and β-tricalcium phosphate ceramics have routinely been sintered at temperatures of 1300°C. The new CaP biomaterials tested are fabricated by a sol-gel process at only 700°C.Study designCritical-size defects (>5 cm3) in the mandible of 15 adult Goettingen minipigs were filled with 1 of the 2 new types of CaP biomaterials, or with 1 of 2 well-known old-type ceramics, or with a gelatin sponge (in the control group). Macroscopical, histological, and morphometric examination of the former defect areas were made 8 months postoperatively.ResultsEight months after implantation of the new CaP biomaterials, complete bone formation was observed in the defect area, and at the same time, the foreign material was resorbed almost completely. After implantation of the classical types of ceramics, only incomplete bone formation and a lesser resorption rate of the foreign bodies were noted. The difference in the bone formation rate was significant: more than 93% for the new CaP biomaterials versus less than 58% for the classical types of ceramics (P < 0.01).ConclusionThe biological behavior of the new CaP biomaterials was better than that of the old-type sintered ceramic bone-grafting materials. These new CaP matrices are suitable for filling bone defects and are of interest for dentists, including implantologists, craniomaxillofacial and orthopedic surgeons, as well as traumatologists.