关键词: 骨组织, 精氨酸-甘氨酸-天冬氨酸, 微种植体, Beagle犬

Abstract:

Objective To investigate the expression levels of collagenⅠ (ColⅠ) and osteocalcin (OC) in the bone tissue around the arg-gly-asp(RGD) peptide coated micro-screw implants in the Beagle's maxilla at different healing time, and to clarify the promotion of RGD-coated surface on the osseointegration of micro-screw implants. Methods Six male adult Beagles were included in this study.Thirty-six micro-implants were randomly divided into two group:experimental group (with RGD) and control group (without RGD)(n=18).A micro implant was inserted in any one of the maxilla implantation regions(furcation zone of second premolar, third premolar, forth premolar) respectively at the 0 week, 4 weeks, and 6 weeeks after experiments by the self-contrast methods, one side was used as the experimental group and another side as the control group.At the 8th week, all animals were sacrificed and the bone specimens were prepared for HE and immunohistochemical staining, and the expression levels of ColⅠand OC in the bone tissue around the micro-implant were detected. Results The Results of HE staining showed that there were more osteogenesis activity both in experimental group and control group at the 2nd and 4th weeks, while lamellar bone could be seen in two groups at the 8th week.The expression levels of ColⅠand OC in the bone tissue around the micro-screw implants in experimental group were obviously higher than those in control group at the 2nd and 4th weeks(P<0.05);but there was no significant difference at the 8th week between two groups(P>0.05).The expression levels of ColⅠin the bone tissue around the micro-screw implants in experimental group were significantly higher at the 4th week than those at the 2nd and 8th weeks(P<0.05), but there was statistical difference only between the 2nd and 8th weeks in control group(P<0.05).The OC expression levels in two groups were increased progressively at the 2nd week and the 4th week, and reached the highest level at the 8th week, and they were obviously higher at the 8th week than those at the 2nd week(P<0.05).When compared with the 2nd week, the OC expression levels in the bone tissue around the micro-screw implants in experimental group at the 4th week had the statistical difference (P<0.05), while no significant difference was found in control group(P>0.05). Conclusion The RGD-coated surface can increase the expressions of ColⅠand OC in the bone tissue around the micro-implants, and it plays a key role in improving the initial osseointegration of micro-implants.

Key words: bone tissue, arg-gly -asp, micro-implant, Beagle dog