Progressive Overgrowth of Costochondral Graft in a Case of Hemifacial Microsomia: A Rare and Severe Case.

Costochondral grafts (CCGs) are widely used for mandibular condyle reconstruction in children due to their growth potential, yet their unpredictable behavior remains a challenge. We present a rare case of progressive CCG overgrowth in a 17-year-old male with hemifacial microsomia, resulting in severe facial asymmetry despite prior corrective surgeries. Clinical assessment revealed a 2.5 cm ramus discrepancy and marked mandibular deviation. Management required staged surgical correction, including graft excision, osteotomies, and genioplasty. This case illustrates the potential for extreme CCG overgrowth beyond skeletal maturity and emphasizes the need for vigilant long-term surveillance and individualized treatment planning.