Repair of bony defect with combination biomaterials

Numerous possibilities are available for the reconstruction of facial bone defects. The materials used to fill such defects must satisfy various requirements. One of the most important is that they must undergo transformation into autologous bone tissue in the process of remodeling.

A report is given of the long-term results of augmentations of large bone defects performed with different bone-substitute materials in two patients.

In one case, augmentation was carried out with beta-tricalcium phosphate after the removal of a fibromyxoma. In the second case, three large cystic lesions in the mandible of a patient with Gorlin-Goltz syndrome were filled with beta-tricalcium phosphate, with a mixture of beta-tricalcium phosphate and platelet concentrate, or with hydroxyapatite of algal origin. The process of ossification was checked at 6-month intervals by means of clinical, radiologic (orthopantomograms and two-dimensional and three-dimensional computer tomograms), and histologic methods.

At 1 year after the intervention, the site of the augmentation was in all cases occupied by hard tissue of good quality. With the given imaging procedures, it was difficult to distinguish between the original bone and the region filled with bone-substitute material. The three-dimensional computer tomogram images indicated that the contours and quality of the new bone corresponded with the physiologic and anatomical conditions. The histologic examinations show the remodeling of the bone-substitute materials.

The bone-substitute materials applied in these cases fully satisfied the demands of transformation into bone (remodeling). The speed of remodeling seemed to be the fastest when the mixture of beta-tricalcium phosphate and platelet concentrate was used.