Abstract
BACKGROUND: Desmoplastic fibroma is a rare, benign but locally aggressive fibroblastic tumor of bone, accounting for less than 0.1% of primary bone neoplasms. The mandible is its most frequent site, and occurrence in children is exceptionally uncommon. Because of its infiltrative behavior and the potential for significant functional and aesthetic consequences in growing patients, determining the optimal treatment approach-particularly the role of emerging non-surgical therapies-remains a clinical challenge. CASE PRESENTATION: A 10-year-old boy presented with a one-year history of progressive, painless swelling of the right mandible. Imaging revealed an expansive mandibular lesion, and incisional biopsy confirmed desmoplastic fibroma. The family sought evaluation regarding both surgical and non-surgical management options, reflecting current therapeutic uncertainty surrounding this rare tumor in pediatric patients. Following multidisciplinary counseling, definitive surgical treatment was chosen. Using virtual surgical planning and patient-specific 3D-printed guides, a segmental mandibulectomy was performed, followed by immediate reconstruction with a vascularized fibula free flap and a prebent reconstruction plate. Microvascular anastomoses were successful, postoperative imaging demonstrated accurate anatomical restoration, and recovery was uneventful with a stable, well-perfused flap. CONCLUSION: This case highlights the diagnostic and therapeutic complexities of pediatric mandibular desmoplastic fibroma and underscores the ongoing debate regarding surgical vs. emerging systemic treatment strategies. Despite increasing interest in non-surgical modalities, wide resection with microvascular reconstruction remains the most reliable approach for achieving durable local control and restoring mandibular continuity in children. Early diagnosis, comprehensive imaging, and advanced virtual surgical planning are essential to optimizing outcomes in these rare and challenging cases.