[Present conception and future of implants in Japanese oral and maxillofacial surgery].

In recent, dental implants have been developed and practiced among many dental practitioners depending on the increase of success rate. Also some types of dental implants have been imported from foreign countries in order to obtain more increased masticatory function and esthetics in Japan. On the other hand, some kinds of implant materials such Co-Cr, titanium, ceramics and artificial materials are provided to reconstruct the mandible combined with autogenous bone graft following excision of tumors in the Japanese oral and maxillofacial surgery field. It is my opinion that the success of reconstructive surgery is based on the reconstruction of mandibular bone and the reconstruction of masticatory function by dental implant on the point of oral rehabilitation to reach that the patient should live in comfort. It is well known that not every reconstruction can be satisfactory due to postoperative infection, implanted substances exposed to intra-oral and/or extra-oral sites and/or resorption of the grafted bone under a long term observation. Based on these reasons, we have reconstructed the mandible with revascularized osteomyocutaneous flaps using the microvascular anastomoses technique to reconstruct the defect and to prevent bone resorption. However, even if the reconstruction was achieved successfully, post-operative problems could come into existence due to masticatory, swallowing or speech dysfunctions. These are often caused by loss of soft tissue, deformities of the alveolar ridge or contour of the mandible. Therefore, some kinds of dental implants have been tried in some countries for the reconstruction of the edentulous mandible in order to improve the post-operative functions. The TM-Implant (Transmandibular Implant), which was deviced by Dr. Hans Bosker, Netherland, is one of these dental implants. We tried to apply for two oral cancer cases who had been resected and/or reconstructed mandibles using this implant as the first experience in our country (Fig. 5). The first patient segmentally resected mandible was reconstructed by the revascularized iliac bone, the second patient was marginal resected mandible with tumor (Fig. 6-13). Results of these two implant cases, using TM-Implant, showed significant improvement of oral function thanks of the stability of dentures after the second phase of reconstruction. Dental implants can attribute the functional improvement for oral cancer patients in the future. Strict diagnosis of the bone condition before surgery and careful surgical procedure, whenever dental implants are used, are required to avoid postoperative complications.(ABSTRACT TRUNCATED AT 400 WORDS)