Patient-Specific 3D-Printed Mold System for Superior Semicircular Canal Third-Window Repair: Design, Fabrication, and...

Superior semicircular canal dehiscence (SSCD) is a pathological defect in the bony labyrinth of the inner ear that produces auditory and vestibular symptoms due to abnormal fluid mechanics. Conventional surgical methods, including canal plugging and resurfacing, often result in partial or total loss of vestibular function. This study reports the design, fabrication, and first clinical validation of a patient-specific, 3D-printed silicone mold system for the anatomical restoration of the superior semicircular canal. Using high-resolution computed tomography (CT), three-dimensional reconstruction, and computer-aided design (CAD), a sterilizable mold conforming to the superior semicircular canal was fabricated. The mold enables ex-vivo casting and shaping of polymethyl methacrylate (PMMA) bone cement to close the pathological third-window defect with precise anatomical alignment. Validation using a 3D-printed temporal bone model confirmed perfect fit and sealing accuracy. The system was then successfully applied in a clinical case, achieving full symptom resolution and preservation of vestibular function. This translational study demonstrates that additive manufacturing can be effectively applied to otologic surgery for patient-specific defect repair, marking a major step toward precision inner-ear reconstruction. Keywords 3D printing; Biofabrication; Patient-Specific Implant; Silicone Mold; Superior Semicircular Canal Dehiscence; Bone Cement; Translational Surgery.