A potent inhibitor for bone resorption, the gem-bisphosphonate zoledronate, has been chemically associated with calcium-deficient apatites. The ability of such materials to release the zoledronate, resulting in the inhibition of osteoclastic resorption, is demonstrated using a specific in-vitro bone resorption model. The resorption activity is typically characterized by the formation of lacunae on the surface of dentin slices (see Figure).
This review focuses on bone substitute composites made by mixing ceramic biomaterials with fibrin sealants.Different biomaterials such as coral, bone-derived materials, bioactive glass ceramics, and synthetic calcium phosphate have been mixed with fibrin sealant, resulting in a combination of the biological properties of the two components.This type of association has not produced identical results in all studies.In the past for some, the addition of fibrin sealant to the biomaterial failed to produce any significant, positive effect on osteointegration, whereas others found a positive impact on bone colonization.Despite the negative biological effects reported previously, bioceramic-fibrin composites have been widely used in various types of bone surgery because they are easy to manipulate.In particular, the intra-operative preparation of these composites makes it possible to add bone growth factors or autologous osteoprogenitor cells prior to bone reconstruction.The bone growth factors and autologous osteoprogenitor cells associated with the bioceramic-fibrin composites should provide surgeons with tissue engineered grafts with enhanced osteointegrative properties.This review discusses both the advantages and disadvantages, as well as the future perspectives, of using bioceramic-fibrin composites in various clinical indications.
We have developed a novel macroporous calcium phosphate cement MCPC® that sets to poorly crystalline apatite after mixing the powder component with an aqueous solution and has interconnective macroporosity We performed cranioplasty on rat model by injecting the new macroporous calcium phosphate cement MCPC®. The mechanical property of the cement is about 12MPa after 24 hours (compression test). The cement matrix is totally transformed into poorly crystalline apatite in 48 hours. This study demonstrates that MCPC® cement was suitable and efficient for parietal bone reconstruction. Its injectability and moldability allows to be used in bone reconstruction surgery and its mechanical properties are compatible to support calvarial reconstruction. In addition, a bone ingrowth onto the BCP granules occurred on time.
Two Ca-P ceramics (MBCP: macroporous biphasic calcium phosphate and Bonap: sintered bovine bone) were implanted in rabbit bone and were studied at days 3, 7, 14 and 21 after implantation. Resorption of the biomaterials and of the newly formed bone was observed from day 7. Two multi- nucleated cell types were involved in the resorption process: giant multinucleated cells (GMNC) and osteoclast-like cells (OLC).
Hydroxyapatite (HA) ceramics are widely used as bone substitutes in the repair of bony defects. These ceramics sometimes differ in their sintering temperatures. High resolution transmission electron microscopy was used to characterize HA ceramics sintered at different temperatures. A new type of defect was observed for the first time for ceramics prepared at 900 degrees C but not on those prepared at 1250 degrees C. This may cause a difference in their in vitro dissolution and in vivo performance.
