Bone Ingrowth into Ti-Zr Porous Implant and Bone Bonding Strength

Abstract

On the basis of data obtained in a cell culture study on the ingrowth speed of bone formative group cells into Ti-Zr porous blocks, two kinds of implants with average pore sizes of 95 μm and 149 μm were used in this experiment. The Ti-Zr porous implants were installed in a beagleʼs upper and lower jawbones to investigate bone occupancy in the pore and bone bonding strength at 5 and 30 weeks post-implantation.
The pore size dependency on the bone occupancy and bonding strength were clearly proved by histometric investigations, statistically compared using ANOVA.5 weeks post-implantation, both pore sizes of 95 μm and 149 μm could not reach the adequate bone bonding strength of 600 N required to keep the implant fixed under functional biting. However, when the 149 μm pore size implants were immersed and cultured for 2 weeks in the medium (MEM＋10% calf serum) with bone formative group cells derived from bone marrow of the host dogʼs femur before the implantation, the implants demonstrated higher bone occupancy in the pore and higher bone bonding strength of 624 N 5 weeks postimplantation compared with 360 N of the 149 μm pore size implants without pretreatment of bone formative group cells. If early loading after implantation is required, it may be effective to treat the porous implant with 14-days-cultivated bone formative cells derived from the patientʼs bone.