The use of biphasic calcium phosphate with or without bone morphogenic protein-2 for bone regeneration during immediate implant placement in a micropig model: A pilot study

Abstract

PurposeThe aim of this pilot study is to investigate bone regeneration in a three wall defect during immediate implant placement, using porous biphasic calcium phosphate (BCP) granules with or without recombinant human bone morphogenetic protein – 2 (rhBMP-2). Materials and MethodsAlveolar defects were created in the mandible of five female, adult micropigs. The lower right 4th premolar was extracted and the buccal cortex removed. Immediate implants were placed and the defect was grafted. Control group (n = 2), received BCP granules and fibrin sealant. The test group (n = 3) received BCP granules in combination with fibrin sealant and rhBMP-2. A collagen membrane was placed over the graft and primary closure of the wound was achieved. The pigs were all euthanized at 6 months after the first surgery. Histology evaluation and histomorphometry analyses calculating % bone implant contact (%BIC) and % bone area (%BA) were performed. ResultsOne pig in the BMP group died prematurely at 3 months after the first surgery. At specimen harvest, there were no dehiscence of all surgical sites and implant survival rate was 100%. The control group demonstrated no new bone formation at the buccal surface of the dental implants at 6 months. The mean %BIC for the BMP group at 6 months was 75.53 ± 12.52%. The mean %BA for the BMP group 6 months was 52.82 ± 3.27%. ConclusionWithin the limitations of this pilot study, the use of rhBMP-2 resulted in significant new bone formation in a non-contained defect around an immediate implant.