Patient-specific sub-periosteal zygoma implant for prosthetic rehabilitation of large maxillary defects after oncological resection.

A 74-year-old woman needed a subtotal bilateral maxillectomy due to squamous cell carcinoma of the palate. Immediate and secondary reconstruction of the defect was not feasible, so the defect was closed with an obturator prosthesis wired to the zygoma complex. To improve the patient's severely impaired speech and swallowing, a patient-specific sub-periosteal implant (psSPI) was designed that matched the remnants of the zygoma complex. First, the patient's post-surgical anatomy was visualized through segmentation of the pre- and post-maxillectomy computed tomography data. Next, based on the data, a customized zygoma-supported framework was designed to support the obturator prosthesis. Surgical guides for intraoperative navigation were designed and three-dimensionally printed, along with an obturator prosthesis to fit the planned outcome situation. The preoperatively manufactured psSPI and obturator prosthesis matched the intraoperative conditions. The postoperative results were favourable; within a week after surgery the patient could speak and swallow normally without nasal leakage. No problems occurred during follow-up. These results indicate that a psSPI-retained prosthesis can be considered for the restoration of speech and oral functioning in cases with a largely compromised maxillary bone anatomy, accompanied by impaired oral functioning and no feasible conventional reconstruction options.