自家腸骨移植を用いた下顎骨再建方法の頭部Ｘ線規格写真による検討 Ｂａｒｓｋｙ法を基準として

Abstract

Mandibular resections are generally carried out for malignant tumors or nonmalignant tumors with tendencies to recur, such as ameloblastoma. Various artificial materials have been used for major discontinuity defects of the mandible combining with autogenous bone graft. Its method is valuable to compensate for disadvantages of inability to supply bone for very large mouth defects and difficulty in providing excellent surface facial contours because of its size and bulk for situations that require artificial material replacement of large defects, as shown in each method which is suitable under different circumstances. On the other hand, morbidity related to bone grafts harvested for reconstruction of major mandibular discontinuity defects have not been studied. It is thought that too long avascularized bone may cause infection, resorption, and partial necrosis.The present study was designed to investigate the relation between the mandibular resection size and the amount of ilium harvested by Barsky's procedure.Forty Indian dry skulls and ilium were used, in which landmarks of Pogonion (Pog), Gonion (Go), mental foramina (Me), mandibular foramina imaged at the cortical bone (Ma), the most prominent point of the iliac crest (A), a point of intersection between the tangent to iliac tubercle and tangent to external labium (B) were noted. Distances were measured of Pog-Go, Pog-Me, Me-Ma and A-B along the cortical bone. Linear measurements of cephalometric radiograph were shown with Pogm-Gom, Pogm-Mem, Mem-Mam, respectively. These linear values were measured along cl. vertical line perpendicular to the mandibular plane. Of the measurements performed on the dry bones, ratios of Pog-Go: Pogm-Gom, Pog-Me: Pogm-Mem, Me-Ma: Mem-Mam were 1.17, 1.53, 1.08 respectively. Ma-Me approximates to A-B. A-B has a relatively constant length, which can utilized as a Ma-Me length for planning a mandibular resection. The plate made based upon these ratios were used for mandibular reconstruction of two cases of odontgenic keratocyst and ameloblastoma. The most satisfactory and comfortable reconstruction for the patients were obtained in both esthetic and functional aspects.It is pointed out that it may be possible to design mandibular reconstruction with iliac bone transplantation using cephalometric measurements for large mandibular defects.