Progressive unilateral mandibular swelling in adolescence: a diagnostic dilemma

Asymmetrical swelling of the mandible in adolescence may pose a significant diagnostic dilemma. The differential diagnosis ranges from traumatic, infectious, and metabolic processes to benign and malignant tumors. Among them, fibrous dysplasia, osteomyelitis, and malignancy may present with similar clinical and radiological features, making an accurate diagnosis quite difficult. This is an illustrative case involving a 14-year-old girl who initially presented with diffuse fibrous dysplasia of the mandible and in whom a superimposed osteomyelitis of the left side subsequently developed. Multiple investigations and several biopsies were required to arrive at a diagnosis. Similarities in clinical and radiographic findings of fibrous dysplasia, osteomyelitis, and malignancy are presented, and implications for treatment are discussed.