Application Of Computer Techniques In Repair Of Oblique Facial Clefts With Outer-Table Calvarial Bone Grafts

Background:Oblique facial clefts are catastrophic facial anomaly involving deformity of facial skin, muscles and craniofacial skeleton. Autogenous bone grafting is the main treatment to close bone cleft and to restore the continuity of the craniomaxillofacial skeleton. In the past, since lack of accurate preoperative design, the clinical outcome were always far from ideal.Objective:This research was aiming to apply the computer aided techniques and rapid prototyping techniques in preoperative design in order to improve the accuracy of surgery.Methods:Five patients with oblique facial clefts were repaired with outer table calvarial bone. Mirror technique and rapid prototyping techniques were applied to design and prefabricate the individualized template for repairing orbital inferior wall and the maxillary anterior wall defects preoperatively. Using computer software, the ideal region to take outer table calvarial bone was located according to the size and surface curvature of the individualized template. Surgical accuracy was evaluated by comparing the preoperative and postoperative3D reconstructed images.Results:All5patients had ideal clinical outcome, with few complications. The three dimensional images of preoperative design and postoperative were superimposed onto each other and fit well. Postoperative follow-up for6months to2years demonstrated that4patients had good aesthetic facial appearances,1patient had developed recurrence of lower eyelid shortage.Conclusion:Computer aided techniques and rapid prototyping techniques can offer surgeons ability to design individualized templates accurately for craniofacial deformity and to perform a simulated operation so that surgical accuracy can be improved greatly.Summary:Basing on clinical, this study applied computer-aided technology to the treatment of oblique facial cleft and solved the difficult problem that lack of accuracy of bone’s reparation. No relevant research has been found at home and abroad. In this study, the depth of excavation advantage of computer-aided technology has been used to solve the problem of the surface oblique fissure bone missing calculation and morphology; provides a new means to optimize the skull plate and orbital floor curvature; In addition, applying image matching function to the assessment of the effect of surgery is a more reliable quantitative evaluation method than the eyes.