Transforming Growth Factor-β3 Therapy Delays Postoperative Reossification and Improves Craniofacial Growth in Craniosynostotic Rabbits.

Postoperative reossification is a common clinical correlate following surgery. It has been suggested that an underexpression of transforming growth factor-beta 3 (TGF-beta 3) may be related to craniosynostosis and postoperative reossification. Adding TGF-beta 3 may delay reossification and improve postoperative growth. The present study was designed to test this hypothesis. Thirty 10-day-old New Zealand white rabbits with hereditary coronal suture synostosis were divided into three groups: (1) suturectomy controls (n = 14), (2) suturectomy treated with bovine serum albumin (n = 8), and (3) suturectomy treated with TGF-beta 3 protein (n = 8). At 10 days of age, a 3-mm x 15-mm coronal suturectomy was performed, and serial threedimensional (3D) computed tomography (CT) scans and cephalographs were taken at 10, 25, 42, and 84 days of age. Calvaria were harvested at 84 days of age for histomorphometric analysis. Mean differences were analyzed using a group by age analysis of variance. Analysis of the 3D CT scan data revealed that sites treated with TGF-beta 3 had significantly (P < .05) greater defect areas and significantly (P < .05) greater intracranial volumes through 84 days of age compared with controls. Histomorphometry showed that sites treated with TGF-beta 3 had patent suturectomy sites and significantly (P< .001) less new bone in the suturectomy site compared with controls. Serial radiograph data revealed significant (P < .05) differences in craniofacial growth from 25 to 84 days in TGF-beta 3-treated rabbits compared with controls. Data show that TGF-beta 3 administration delayed reossification and improved craniofacial growth in this rabbit model. These findings also suggest that this molecular-based therapy may have potential clinical use.