アパタイトセラミックス・インプラントの骨組織による保持に関する組織学的研究

Abstract

Investigation was conducted to determine the correlation of the osseous ability of the bone to retain the apatite ceramics implant with the structure of the mandible and the formation of the bone around the implant.First, the tensile strength between the bone and the implant was determined by the tension test between the apatite pellets placed in the dog tibia and the bone tissue around the implant. The highest tensile strength value obtained was 65.7 kg/cm2. Second, by the push-out test of the cylindrical apatite implant placed in the dog lower jaw, the strength of the bone to retain the implant was determind. The highest extrusive strength value obtained was 300kg.Histological observation of the implant specimens under the transmission light and electron microscopes after the mechanical test indicated that the strength of the bone to ratain the implant increased in the course of time and as the bone formation advanced. Fracture caused by the mechanical strength test was found to occur inside the bone or apatite ceramics, not at the interface between the bone and the material. The push-out test and histological observation produced particularly interesting results clinically : the strength of the bone to retain the implant depended greatly on the volume of the newly formed bone one month after the implantation and on the structure of the mandible afterward.