Bicalcium phosphate filling-up after calvarial unicortical harvesting in maxillofacial surgery

The calvarium is one of the most common donor sites for bone grafting in maxillofacial and craniofacial surgery. The quality of the bone and the few after-effects that arise in calvarium make it a very good choice for reconstruction, especially in preprosthetic surgery. Nevertheless, calvaria harvesting of the outer table can leave a depression on the scalp, which can be perceptible and palpable. This point is always difficult to assume for patients. This absence of outer-layer reconstruction of the skull could also lead to a modification of biomechanical characteristics and fragility of the skull. This is the reason why we decided to fill up the donor site with an osseoconductive biomaterial: bicalcium phosphate. To evaluate this reconstruction, we reviewed 20 patients who have undergone this procedure. All patients have been seen 6 months after surgery, 11 of them with computed tomographic scans of the donor site. An aesthetic evaluation of the result was made by the patient through a questionnaire. With computed tomographic scans, we made qualitative and quantitative evaluations of the donor site. For 2 patients of them, histologic examination was performed to evaluate newly formed bone. The results of this study suggest that filling in the donor site with bicalcium phosphate improves the tolerance of calvaria harvesting. Bone colonization of the osseoconductive biomaterials leads to the formation of a new outer table of the skull. Taking into account the quality of the calvarial bone and the restoration of the donor site, calvaria harvesting is, in our hands, one of the best choices in craniofacial and maxillofacial reconstruction.