[Establishment of immediate implant animal model in mongrel dog's fresh extraction socket]

The purpose of the study was to establish the animal models which had clinical characteristics in bone defect sizes around immediate implants. The mesial region of dogs' fresh extraction sockets were made with 3 mm x 3 mm x 5 mm size bone defects around implants with a round bur, then observed their osseous changes at 2 weeks, 4 weeks, 8 weeks, 12 weeks with and without demineralized freeze-dried bone allograft (DFDBA) filled. The results showed that the bone defects in DFDBA grafted group were substituted by new bone, but the defects in ungrafted group were only substituted to 3/5. Such animal models had the advantages of simple preparations and similar clinical characteristics, so they were beneficial to investigation of the immediate implantation.