Foundation And Clinical Research Of Osteotomy Of The Outer Mandibular Cortex Combined With Coralline Hydroxyapatite Implantation For Treatment Of Hemifacial Microsomia

Purpose:1. To evaluate the effect of the osteogenesis of the compound of CHA+VEGF+FS as composite scaffold materials and study the effect of this new method. Using osteotomy of the outer mandibular cortex combined with the compound of CHA+VEGF+FS in miniature pigs to treat mandibular hypoplasia caused by hemifacial microsomia, provide the necessary theoretical basis for clinical application in the future.2. To observe the clinical effect of osteotomy of the outer mandibular cortex combined with CHA implantation for mandibular hypoplasia caused by Pruzansky Kaban type I or type Ⅱa hemifacial microsomia. To evaluate the postoperative effect of the method and analyse the range of application and the advantage of the method of the surgery may exist.Method:1.10miniature pigs at age9-12months were selected as the experimental animals which were divided into2groups randomly:group A and group B. In group A, the outer cortex of mandibular body and angle was split in one side and the compound of CHA+VEGF+FS was implanted into the gap between the outer and inner cortex of mandible, with the other side as control. In group B, two kinds of compounds (leftside:the compound of CHA+VEGF+FS:the compound of CHA+FS) was implanted into the gaps with the same methods separately. The osteogenesis and effect of this method by morphological, histological, radiological observation and biomechanical testing.2. There were6patients of Pruzansky-Kaban type I or type Ⅱa hemifacial microsomia treated with the method of osteotomy of the outer mandibular cortex combined with coralline hydroxyapatite implantation. Follow-up visits were conducted for6to24months to monitor4of the patients. To observe the postoperative effect by the imaging, skull X-ray, CT three dimensional reconstruction.Result:1. Both of the compound of CHA+VEGF+FS and the compound of CHA+FS after implantation could increase the width of the mandible effectively. But the compound of CHA+VEGF+FS was higher than the compound of CHA+FS in the degree of vascularization in the early time, and achieved bone mature much earlier after implantation by histological observation. On the bone resorption rate of the test, the compound of CHA+VEGF+FS was lower than the compound of CHA+FS. After6months, the two implant materials showed that there was no evident difference with normal bone tissue by the histomorphology, scanning electron microscopy of ultrastructure observation and the implant had no obvious effect on maximum stress.2. With the thickness of mandibular increased significantly after6months, significant improvements in the asymmetry of the mandible as well as in the aesthetic appearance of all the patients were observed.Conclusion:1. The results of this pilot study indicate that the osteotomy of the outer mandibular cortex combined with the compound of CHA+VEGF+FS may be useful for the augumentation of width of mandible. This study provided a theoretical basis for clinical use of this new method.2. The osteotomy of the outer mandibular cortex combined with CHA implantation is a useful method for Pruzansky-Kaban type I or type Ha hemifacial microsomia in patients with mandibular hypoplasia.