Th purpose of this study is to compare the possibility of the clinical sue of titanium dental implant together with allogeneic bone powders or with other bone substitutes. The allogeneic bone powders which were freeze dried and demineralized in
Korea
Biomaterial Research Institute. Dankook University, resorbable hydroxyapatite (HA) particles, or nonresorbable HA particles combined with plaster were transplanted at the bone defect around the implant fixture which was inserted in the femur of
the
dogs. The dogs were sacrificed 1, 3. and 6 months postoperatively and the bonding strength were examined between the titanium implants and the surrounding new bone. The histological response of the tissue surrounding the implants were observed
with the
LM, SEM, and TEM.
@ES The results were as followed:
@EN 1. In Experimental Group each torque strength was gauged 3, 13, 28 NCm at 1, 3, 6 month, in Control group was 2, 19, 22 NCm, in comparative Group I was 3, 16, 24 NCm, and in Comparative Group II 2, 16, 32 NCm.
2. New bone was partially attached at the surface of the titanium dental impiant 1 month postoperatively in all Groups. Laminate bone was observed at the large portion of the surface of the implant in all groups 6 months postoperatively.
3. In Experimental Group. the large portion adjacent to the implant fixture was replaced by the new bone trabeculae 1month postoperatively. Harversian canals seemed to be in remodelling process 6 moths posto peratively, and the laminated
structures
were also seen in the bone adjacent to implants.
4. In the marrow far from the implant fixture, the large multinucleated cells osteoclasts and the mononucleated simple cuboidal cells were aligned at the surface of the bone particles, and the mononucleated cells were observed being bridged
between two
particles. The lacunae of the bone particles were filed with the osteocyte.
5. In comparative Group II, nidus of bone was seen around the HA particles 1 month postoperatively. Laminated bone was observed around the implant fixture and new bone formation was seen around the nonresorbable HA particles 3,6 months
postoperatively.
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