Adipose stem cell tissue-engineered construct used to treat large anterior mandibular defect: a case report and review of the clinical application of good manufacturing practice-level adipose stem cells for bone regeneration

Abstract

Purpose: Large mandibular resection defects historically have been treated using autogenous bone grafts and reconstruction plates. However, a major drawback of large autogenous bone grafts is donor-site morbidity.

Patients and methods: This report describes the replacement of a 10-cm anterior mandibular ameloblastoma resection defect, reproducing the original anatomy of the chin, using a tissue-engineered construct consisting of β-tricalcium phosphate (β-TCP) granules, recombinant human bone morphogenetic protein-2 (BMP-2), and Good Manufacturing Practice-level autologous adipose stem cells (ASCs). Unlike prior reports, 1-step in situ bone formation was used without the need for an ectopic bone-formation step. The reconstructed defect was rehabilitated with a dental implant-supported overdenture. An additive manufactured medical skull model was used preoperatively to guide the prebending of patient-specific hardware, including a reconstruction plate and titanium mesh. A subcutaneous adipose tissue sample was harvested from the anterior abdominal wall of the patient before resection and simultaneous reconstruction of the parasymphysis. ASCs were isolated and expanded ex vivo over the next 3 weeks. The cell surface marker expression profile of ASCs was similar to previously reported results and ASCs were analyzed for osteogenic differentiation potential in vitro. The expanded cells were seeded onto a scaffold consisting of β-TCP and BMP-2 and the cell viability was evaluated. The construct was implanted into the parasymphyseal defect.

Results: Ten months after reconstruction, dental implants were inserted into the grafted site, allowing harvesting of bone cores. Histologic examination and in vitro analysis of cell viability and cell surface markers were performed and prosthodontic rehabilitation was completed.

Conclusion: ASCs in combination with β-TCP and BMP-2 offer a promising construct for the treatment of large, challenging mandibular defects without the need for ectopic bone formation and allowing rehabilitation with dental implants.