Journal of implantology and applied sciences ISSN:2765-7833(Print) 2765-7841(Online) 대한구강악안면임플란트학회지

Titanium implant that had been designed to have different gap (50㎛, 100㎛, 150㎛, and 250㎛ respectively) in titanium-bone interface were inserted into tibia of rabbit for 1 week, 2 weeks 3 weeks and 4 weeks. And then the characteristics of the new bone ingrowth into the gap which had been made at the titanium-bone interface were studied. That is, we studied the pattern of bone healing, the proportion of contact length between titanium implant and bone, and the proportion of new bone volume grown into gap space. The results were as follows: 1. The histologic finding of the gap between titanium and bone during wound healing 1) In 1-week group, inflammatory cells, fibroblast-like cells, osteoblasts, polymorphonuclear leukocytes, and erythrocytes were observed in a mixed shape around the titanium implant. And the fibrin of blood clot was observed with erythrocytes, macrophages, and fibroblasts. New blood vessels were observed also. New bone tissue was being made along the osteoblast cell layer. 2) In 2-week group, ingrowth of the bone trabecula lined by active osteoblast was observed in the gap space, and many osteocytes were entrapped in bony trabecula though the trabecular pattern was not compact. 3) In 3-week group, it was observed that new bone was contact directly with titanium implant, but in many sites, the fibroblast-like cell layer was intervened. 4) In 4-week group, the trabecular pattern had been disappeared in many specimen and was changing into compact bone in some. The titanium layer of implant and bone tissue had direct contact, but almost all of 250㎛ gap group had lower level of ossification than the 100㎛ gap group and had the osteoblast or fibroblast-like cell layer interface. 2. In general, the remodeling of new bone was observed in 3-and 4-week group. 3. The smaller the gap was, the higher the contact length fraction between titanium implant and new bone was. But the difference of means became small on 4-week. 4. The bone ingrowth fraction was appeared to depend on the gap size, i.e. the smaller the gap size was, the higher the bone ingrowth fraction marked. Especially, the difference of the means between 100㎛ and 250㎛ gap group was significant. But the difference of the bone ingrowth fraction onto the size of gap became small time after time. 5. In 2-and-3-week group, bone ingrowth fraction had more difference upon the size of gap between titanium implant and bone than the difference of contact length fraction. So it was likely that gap size had more effect on bone ingrowth fraction than on contact length fraction.