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Bony fixation of implants during the early phase of healing is important in order to get secondary stability of the implant assuring the success of the treatment. Because the successful placement of the implant is limited by the quality and quantity of bone, other agents which stimulate bone formation in the peri-implant spaces has been illustrated. Platelet-derived growth factor (PDGF) has been shown to regulate DNA and protein synthesis in bone cells in vitro and to interact synergistically to enhance soft tissue wound healing in vivo. The purpose of this study was to evaluate bone promotion around implants which were augmented with sagittal split osteotomy or autogenous veneer bone graft using the platelet derived growth factor(PDGF). After placement of newly designed twenty four screw-type implants, which were 12mm in length and 4mm in diameter in 6 dogs. 4microgram of PDGF B/B was applied with surgicel carriers. The dogs were sacrificed at 3 days, 1, 2, 3, 6, and 12 weeks after implantation. Specimens were examined clinically, radiographically, histologically, and histomorphometrically. The results were as follows: 1. Clinically and radiologically, there was no significant difference in bone formation and healing pattern between experimental and control group. 2. In autogenous veneer bone graft group, bone formation was observed at 1st week in the experimental groups but 2nd week in the control groups. At 3rd week, the expeimental groups showed more bone formation comparing to the control groups. 3. In sagittal split osteotomy group, bone formation was observed at 1st week in both groups. But the experimental groups showed more bone formation comparing to the control groups after 2nd week. 4. The bone growth rate of experimental group was more rapid than that of control group. These results indicated that PDGF did not affect the initiation of new bone formation, but it accelerated the bone formation at the early period.
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