Lateral ridge augmentation using particulated or block bone substitutes biocoated with rhGDF‐5 and rhBMP‐2: an immunohistochemical study in dogs

Abstract

AbstractObjectives: The aim of the present study was to immunohistochemically evaluate lateral ridge augmentation using a particulated (BOG) or block (BOB) natural bone mineral biocoated with rhGDF‐5 and rhBMP‐2 in dogs.Materials and methods: Three standardized box‐shaped defects were surgically created at the buccal aspect of the alveolar ridge in each quadrant of eight beagle dogs. After 2 months of healing, the chronic‐type defects were randomly allocated in a split‐mouth design to either (i) BOG or (ii) BOB biocoated with (a) rhGDF‐5 or (b) rhBMP‐2, respectively. Uncoated grafts served as controls. After 3 and 8 weeks, dissected blocks were prepared for immunohistochemical [osteocalcin (OC)] and histomorphometrical analysis [e.g. area (mm2) of new bone fill (BF), newly formed mineralized (MT) and non‐mineralized tissue (NMT)].Results: rhBMP‐2 biocoated BOG revealed significantly highest BF and MT values at 3 (upper and lower jaws – UJ/LJ – compared with BOG) and 8 weeks (UJ – compared with rhGDF‐5). Biocoating of BOB using both rhGDF‐5 and rhBMP‐2 resulted in significantly increased MT values at 8 weeks (UJ/LJ – compared with BOB). In all groups, NMT adjacent to BOG and BOB scaffolds revealed pronounced signs of an OC antigen reactivity.Conclusions: Within the limits of the present study, it was concluded that both rhGDF‐5 and rhBMP‐2 have shown efficacy; however, their bone regenerative effect was markedly influenced by the carrier.