1997 年 10 巻 4 号 p. 463-476
Mandibular reconstruction is performed with free bone grafts of the scapula, ilium, fibula, and ribs with vascular pedicles. Osseointegrated implants are currently set in the reconstructed mandible for functional restoration. In this study, vascularized bone grafts appropriate for mandibular reconstruction were evaluated for subsequent implant grafting in the reconstructed mandible. The cross sectional internal structures of the maxilla and mandible, as well as the scapula, ilium, fibula, and ribs, which were used as vascularized bone grafts, were examined by scanning electron microscopy, and their bone morphometric features were compared. The total cross sectional area of the bone and the area of the mineralized part of the bone were measured as the total bone tissue and the total mineralized bone respectively, and the percentage of mineralized bone in the total bone tissue was calculated. The following observations were made by comparison of these bone morphometric parameters in various donor bones with those in the maxilla and mandible.
The results were as follows:
1. The total amount of bone tissue is a parameter of the amount of bone. It was the largest in the ilium, in which it was comparable to that of the mandible, followed by the scapula, fibula, and ribs in that order.
2. The percentage of mineralized bone in the total bone tissue was 38.38% in the maxilla and 63.36% in the mandible, and the difference in the percentage of mineralized bone was considered to be a factor in the difference in the success rate of implant surgery between the maxilla and mandible.
3. Among the bone grafts used for mandibular reconstruction, the percentage of mineralized bone was the highest in the fibula followed by the scapula, ilium, and ribs in that order. The ilium, which is used frequently for reconstruction surgery, had a low percentage of mineralized bone.
4. The percentage of mineralized bone decreased with age in the maxilla, scapula, ilium, fibula, and ribs, but it did not change with age in the mandible.
5. The ribs were considered from their low total amount of bone tissue and percentage of mineralized bone to have inadequate strength as the base of implants for restoration of masticatory function.
