SRY-box transcription factor 9 and insulin-like growth factor 1 as potential regulators in the pathogenesis of unilateral condylar hyperplasia: a pilot study.

Unilateral condylar hyperplasia (UCH) is a rare growth disorder characterized by progressive mandibular asymmetry. The imbalance in bone activity within the mandibular condyles can lead to masticatory dysfunction and esthetic concerns. Although several associated factors have been proposed, the precise etiology of UCH remains unknown. In this prospective study, we analyzed the expression patterns of SRY-box transcription factor 9 (SOX9) and insulin-like growth factor 1 (IGF-1) in condylar tissues from 11 patients with UCH treated by proportional condylectomy and compared them to condylar samples from five control patients with other mandibular requiring normal condyles to be included in a mandibular resection benign pathology. Resected condyles were demineralized, paraffin-embedded, and subjected to histological and immunohistochemical analysis. Results demonstrated a marked overexpression of SOX9 (P = 0.0080) and IGF-1 (P = 0.0009) in UCH specimens compared to controls, and a significant association with histopathological type according Slootweg classification (r = 0.9017, P = 0.0014 for SOX9 and r = 0.6549, P = 0.0471 for IGF-1). These findings suggest that SOX9 and IGF-1 may be key players in the signaling pathways underlying UCH, providing new insights into its pathophysiology and offering potential targets for future therapeutic strategies in skeletal growth disorders.