Application of Fixed Implant Superstructures Following Multistage Maxillary Reconstruction in Osteosarcoma Patients: A Case Report.

Extensive resections of the maxillary bone often result in significant defects that affect oral functions, such as speech and chewing. Although dentomaxillary prostheses are common, they frequently lead to instability and reduced chewing ability. Vascularized bone grafts, including the fibula, are increasingly used to address these challenges due to their anatomical suitability and functional restoration benefits. Despite advances, problems remain, including insufficient bone height for stable implantation. A 60-year-old Japanese woman presented with swelling of the right maxilla and nasal obstruction and was diagnosed with osteosarcoma. Following chemotherapy and partial maxillary resection, she experienced discomfort with dentomaxillary prosthetics, prompting subsequent reconstruction with fibula and particulate cancellous bone and marrow (PCBM) grafts. This patient was taking methotrexate regularly for rheumatoid arthritis, so there was concern that she would be immunosuppressed. Therefore, we did not choose a zygomatic implant, which would be difficult to control in the event of infection. In addition, the fibula alone was insufficient for reconstruction; sufficient vertical and horizontal bone augmentation was required, and we chose a combination of titanium mesh and PCBM that met these requirements. Sequential implant procedures culminated in fixed superstructures that significantly improved occlusal function and prosthetic stability over a 6-year follow-up period. This case highlights the challenges of prosthetic instability following maxillary resections and demonstrates the effectiveness of multistage reconstructions using fibula grafts and PCBM for alveolar ridge augmentation. The structured approach to maxillofacial reconstruction provides valuable insights into optimizing functional outcomes following surgical procedures and highlights the importance of tailored treatment strategies in complex maxillofacial cases.