Dental Implant Treatment for the Reconstructed Mandible Using a Custom-Made Titanium Mesh Tray and PCBM: 4-Case Report

Currently, large mandibular defects have been treated using autogenous vascularized bone grafts such as fibula, ilia, or scapula. However, this conventional method is technically difficult to reproduce the original mandibular configuration, and has donor site morbidity as a major drawback. Moreover, the establishment of reasonable intermaxillary relationship between the reconstructed mandible and maxilla is not easy. To overcome the mentioned difficulties, we fabricated a computer-assisted designed custom-made titanium-mesh (Ti-mesh) tray for mandibular reconstruction. During reconstructive surgery, we pack particulate cancellous bone and marrow (PCBM) harvested from the iliac crest into the Ti-mesh tray which configuration is almost same as the original mandible. After successful reconstruction, occlusal recovery was done by dental implants.

The objective of this study is to introduce the clinical course of 4 cases and to evaluate the usefulness of our mandibular reconstruction.

Case 1 is an 11-year-old girl with ossifying fibroma in the left mandible who underwent segmental mandibulectomy (#35 - ramus) and immediate mandibular reconstruction. Two dental implants were surely placed in the reconstructed mandible without additional alveoloplasty. Case 2 is a 47-year-old man with ameloblastoma in the right mandible who underwent segmental mandibulectomy (mandibular angle - #32) and immediate mandibular reconstruction. Four dental implants were surely placed in the reconstructed mandible with additional alveoloplasty. Case 3 is a 47-year-old man with ameloblastoma in the mid mandible who underwent segmental mandibulectomy (#46 - #33) and immediate mandibular reconstruction. Five dental implants were surely placed in the reconstructed mandible with additional alveoloplasty. Case 4 is a 57-year-old man with keratocystic odontogenic tumor in the right mandible who underwent segmental mandibulectomy (#31 - #47) and immediate mandibular reconstruction. Four dental implants were surely placed in the reconstructed mandible with additional alveoloplasty.

In each patient, their satisfaction level with postoperative facial contour and oral function was recorded. Bone density and implant stability at the implant placement were also investigated.

All surgical reconstructions were successful and the clinical design for placement of dental implants and superior prosthesis were not difficult. No patients encountered perioperative complications. No local recurrence of tumor was observed. In all cases, excellent new bone formation was recognized and expected results were radiologically achieved. Moreover, naturally symmetrical facial contour was re-produced. A total of 15 implants in 4 patients were placed without failure, and final prosthetic rehabilitations were completed. In all cases, bone density was the type Ⅲ or Ⅳ in accordance with the Lekholm and Zarb index. The primary stability at the time of implant placement was 60 to 81 with ISQ values, and secondary stability at the time of second stage surgery was 75 to 86 with ISQ values. A 23-33 month follow-up of the implants revealed no clinical or radiographic signs suggesting implant failure. All cases were fully satisfied regarding their facial contour and the functional aspects of their prosthetic restoration.

Therefore, our mandibular reconstruction is suggested to be useful for recovery of natural facial contour and occlusal reconstruction.

References:

1. Yamada H, Nakaoka K, Horiuchi T, Kumagai K, Ikawa T, Shigeta Y, Imamura E, Iino M, Ogawa T, Hamada Y: Mandibular reconstruction using custom-made titanium mesh tray and particulate cancellous bone and marrow harvested from bilateral posterior ilia. J Plast Surg Hand Surg, 48(3):183-90, 2014.
2. Matsuo A, Chiba H, et al. Bone quality of mandibles reconstructed with particulate cellular bone and marrow and platelet-rich plasma. J Cranio-Maxillofac Surg, 39 :628-32, 2014.