Biomaterials in the Reconstruction of the Oral and Maxillofacial Region.

Reconstruction of maxillofacial bones has proven to be complex due to the aesthetic requirements and functional demands of the jaw. Although autogenous bone grafts and a wide range of biomaterials are routinely used for facial bone reconstruction, these methods are associated with a number of drawbacks, including the limited availability of autogenous grafts and the morbidity associated with bone graft harvesting, whilst biomaterials are also linked with a high failure rate. These limitations have inspired the search for innovative techniques for bone bioengineering and the development of more reliable biomaterials. Tissue engineering approaches yield powerful tools for long-term satisfying results enabling customized reconstruction and the support of natural healing processes. There is no doubt that further advances in tissue engineering are essential to achieve reliable and satisfactory clinical outcomes for patients. This chapter will highlight the clinical application of biomaterials and provide an overview of the current scientific concepts in the field.

Radiological assessment of bioengineered bone in a muscle flap for the reconstruction of critical-size mandibular defect.

This study presents a comprehensive radiographic evaluation of bone regeneration within a pedicled muscle flap for the reconstruction of critical size mandibular defect. The surgical defect (20 mm × 15 mm) was created in the mandible of ten experimental rabbits. The masseter muscle was adapted to fill the surgical defect, a combination of calcium sulphate/hydroxyapatite cement (CERAMENT™ |SPINE SUPPORT), BMP-7 and rabbit mesenchymal stromal cells (rMSCs) was injected inside the muscle tissue. Radiographic assessment was carried out on the day of surgery and at 4, 8, and 12 weeks postoperatively. At 12 weeks, the animals were sacrificed and cone beam computerized tomography (CBCT) scanning and micro-computed tomography (µ-CT) were carried out. Clinically, a clear layer of bone tissue was identified closely adherent to the border of the surgical defect. Sporadic radio-opaque areas within the surgical defect were detected radiographically. In comparison with the opposite non operated control side, the estimated quantitative scoring of the radio-opacity was 46.6% ± 15, the mean volume of the radio-opaque areas was 63.4% ± 20. Areas of a bone density higher than that of the mandibular bone (+35% ± 25%) were detected at the borders of the surgical defect. The micro-CT analysis revealed thinner trabeculae of the regenerated bone with a more condensed trabecular pattern than the surrounding native bone. These findings suggest a rapid deposition rate of the mineralised tissue and an active remodelling process of the newly regenerated bone within the muscle flap. The novel surgical model of this study has potential clinical application; the assessment of bone regeneration using the presented radiolographic protocol is descriptive and comprehensive. The findings of this research confirm the remarkable potential of local muscle flaps as local bioreactors to induce bone formation for reconstruction of maxillofacial bony defects.