Mandibular reconstruction using a calcium phosphate/polyethylene glycol hydrogel carrier with BMP-2


  • Conflict of interest and source of funding statement

    R. Gruber, S. Krohn, K. Lange, C. Perske, H. Schliephake declare that they have no conflict of interests. M. Dard is an employee of Institute Staumann AG, Basel, Switzerland. C. Mauth, A. Molenberg were employees of Institute Staumann AG, Basel, Switzerland. The study has been funded by the Institut Straumann AG, Basel Switzerland. The study has been supported by the Commission for Technology and Innovation CTI of Switzerland No. 9201.1 PFLS-LS.

  • R.M. Gruber and S. Krohn contributed equally to this work.



To test the hypothesis that a synthetic hydroxyapatite/β-tricalcium phosphate (HA/TCP) construct combined with polyethylene glycol (PEG) hydrogel including recombinant human bone morphogenetic proteins-2 (rhBMP-2) enhances new bone formation compared with bone morphogenetic proteins-2 (BMP-2) delivered using the HA/TCP construct alone.

Material and Methods

Bilateral mandibular partial thickness 20 × 8 × 8 mm (L × W × H) alveolar defects were surgically created in the edentulated posterior mandible in 18 female minipigs. Randomized into two groups of nine animals each, the alveolar defects either received HA/TCP or HA/TCP/PEG with or without BMP-2 (105 μg/defect) in contra-lateral sites using a split-mouth design. Primary outcome, bone density (%) within four regions of interest, was evaluated following a 4-week healing interval when the animals were killed for histometric analysis.


Bone morphogenetic proteins-2 loaded onto HA/TCP constructs significantly enhanced new bone formation compared with HA/TCP controls. Adding PEG apparently obstructed BMP-2 induced bone formation.


Polyethylene glycol compromises the osteogenic effect of BMP-2.