PURPOSE: This study was performed in order to compare the osseointegration of 4 different surfaced implants in the dog's tibia which has thick dense cortical bone and loose marrow space. MATERIALS AND METHODS: Four mongrel dogs and four different surface types of implants, smooth surfaced AVANA implants, RBM surfaced AVANA implants, HA-coated Steri-Oss implants and SLA Bicon implants, were used in this study. The animals were divided into 4 groups on the basis of implant surface characteristics: Control group, RBM group, HA group, and SLA group. Three implants of each group were installed into the metaphysis of tibia of adult dogs. The animals were sacrificed at 8 weeks after implantation. The undecalcified specimens were prepared for histological examination and histomorphometric analysis of implant-bone contact ratios. RESULTS: Radiographically and histologically good osseointegration of implant was observed in the dense cortical bone, but poor osseointegration was observed in the marrow space. Histologically more bone apposition to implant surface was found in rough surfaced groups than the smooth surfaced, Control group. In histomorphometric findings of cortical bone the average bone-implant contact ratios of HA group (95.4%, p<0.01), RBM group (87.1%, p<0.05), and SLA group (86.0%, p<0.05) were significantly higher than that of Control group (75.9%). In marrow space the average bone-implant contact ratios of HA group (76.1%, p<0.01) and SLA group (45.4%, p<0.05) were significantly higher than that of Control group (29.6%). The ratio of RBM group was higher than that of Control group but there was no significantly difference between RBM group and Control group. CONCLUSION: These results suggest that the rough surfaced implants can obtain the better osseointegration than the smooth surfaced implant in the cortical and marrow space and that HA-coated implants can obtain the best osseointegration in the marrow space among them.
Adult ; Animals ; Bone Marrow ; Dogs* ; Humans ; Osseointegration* ; Tibia*

PURPOSE: In the present study, the effects of bFGF on the early responses of proliferation of UMR 106-01 osteoblast cells during cell cycle reentry from the latent(G0/G1) to the proliferative periods(S/M) were investigated. MATERIALS AND METHODS: The synchronized cell culture method using the serum starvation was utilized. After the addition of bFGF, the time courses of protein synthesis, DNA synthesis, thymidylate synthase(TS) activity, TS mRNA level and expression of c-fos were determined. RESULTS: 87% UMR 106-01 cells were synchronized to G0/G1 by serum starvation for seven days in the medium containing 0.1% serum. The protein level began to increase 3 hours after bFGF treatment and reached the maximum at 18 hours. TS activity began to increase 3 hours after the bFGF treatment and reached its peak at 6 hours while its mRNA level, determined by quantitative PCR, reached the maximum at 12 hours. The expression of c-fos protein, determined by western blot analysis and immunocytochemistry, increased 3 hours after bFGF treatment. On the contrary, these prominent changes and responses to bFGF were not observed in the case of using non-synchronized cells cultured in the medium containing 10% serum. CONCLUSION: Based on these data it can be concluded that bFGF-induced DNA synthesis in the early proliferative phase is due to increases in both TS activity and mRNA amount and that the increase in c-fos expression and TS activity occur before the increase in TS mRNA level.
Blotting, Western ; Cell Culture Techniques ; Cell Cycle ; DNA ; Fibroblasts* ; Immunohistochemistry ; Osteoblasts* ; Polymerase Chain Reaction ; RNA, Messenger ; Starvation ; Thymidylate Synthase*

PURPOSE: In the present study, the effects of bFGF on the early responses of proliferation of UMR 106-01 osteoblast cells during cell cycle reentry from the latent(G0/G1) to the proliferative periods(S/M) were investigated. MATERIALS AND METHODS: The synchronized cell culture method using the serum starvation was utilized. After the addition of bFGF, the time courses of protein synthesis, DNA synthesis, thymidylate synthase(TS) activity, TS mRNA level and expression of c-fos were determined. RESULTS: 87% UMR 106-01 cells were synchronized to G0/G1 by serum starvation for seven days in the medium containing 0.1% serum. The protein level began to increase 3 hours after bFGF treatment and reached the maximum at 18 hours. TS activity began to increase 3 hours after the bFGF treatment and reached its peak at 6 hours while its mRNA level, determined by quantitative PCR, reached the maximum at 12 hours. The expression of c-fos protein, determined by western blot analysis and immunocytochemistry, increased 3 hours after bFGF treatment. On the contrary, these prominent changes and responses to bFGF were not observed in the case of using non-synchronized cells cultured in the medium containing 10% serum. CONCLUSION: Based on these data it can be concluded that bFGF-induced DNA synthesis in the early proliferative phase is due to increases in both TS activity and mRNA amount and that the increase in c-fos expression and TS activity occur before the increase in TS mRNA level.
Blotting, Western ; Cell Culture Techniques ; Cell Cycle ; DNA ; Fibroblasts* ; Immunohistochemistry ; Osteoblasts* ; Polymerase Chain Reaction ; RNA, Messenger ; Starvation ; Thymidylate Synthase*