Modern technology complements classic technique: 3D-printed inter-locking cutting guides for frontal sinus osteoma resection and reconstruction with split-calvarial bone graft.

Introduction: Frontal sinus osteomas are rare benign tumors that may cause functional or cosmetic concerns. Virtual surgical planning (VSP) offers promising adjuncts to classic craniofacial techniques to improve surgical precision and minimize long-term morbidity. Patient: A previously healthy 15-year-old male presented with a two-year history of headaches and a slowly enlarging mid-forehead mass. Imaging revealed a 3 × 2 cm frontal sinus osteoma with mucocele formation and erosion of both the anterior and posterior tables, with early mass effect on the frontal lobes. VSP was used to design bi-frontal craniotomy and split-calvarial bone graft cutting guides. A combined approach by plastic surgery and neurosurgery was performed using resorbable plating for reconstruction. Results: The operation proceeded without complication. The osteoma was excised, cranialization of the frontal sinus was completed, and the frontal bone was reconstructed using a split-calvarial bone graft secured with resorbable fixation. The patient recovered uneventfully and was discharged on postoperative day four. At six-month, one-year and two-year follow-up, he remained asymptomatic, with six-month imaging showing stable reconstruction and no tumor recurrence. Pathology confirmed a mixed-type osteoma. Conclusion: This case illustrates the successful application of VSP, split-calvarial grafting, and resorbable plating for the resection and reconstruction of a frontal sinus osteoma. The use of patient-specific guides allowed for precise resection and autologous reconstruction. This technique may serve as a valuable model for similar cases in craniofacial surgery.