In-vivo-Testung eines neuartigen bFGF/TCP-Composite

Autologous bone graft is the golden standard for bone replacement materials. Unfortunately it is limited and has side effects in about 10%. Aim of the study was to determine bone-regenerative effects of a new bFGF/TCP-composite, consisting of basic fibroblast growth factor and a newly developed, in-situ hardening and resorbable tricalcium phosphate cement (TCP), and to compare it with autologous bone graft. Materials and methods: In the first part of the study a trepanation defect of 1,5 mm in the femur diaphysis of male rats was filled with pure TCP or with the bFGF/TCP-composite with different contents of bFGF (0, 2, 20 or 200 µg bFGF/cm³ TCP). As controls we used autologous bone graft and the untreated defect. After 1 or 3 weeks the slides were examined by fluorescence microscopy of an intravitale fluorescence staining to show the dynamic of bone ingrowth, histology, histomorphometry, electron microscopy, microradiography and biomechanically with a three point bending test. In the second part of the study a 9,4 mm trepanation in the distal femur epiphysis of adult sheep, was filled with the bFGF/TCP-composite with a content of 200 µg bFGF/cm³, pure TCP, autologous bone graft or left empty. After 12 weeks the bone probes were examined by x-ray, fluorescence microscopy, computertomography, histology, histomorphometry and microradiography. Results: In the first part of the study fluorescence microscopy showed a time-dependend ingrowth of bone up to the middle of the defect. Microradiographie showed the same results. Furthermore microradiography and electron microscopy showed a closed contact between cement and newly formed bone. Histology certified the results and besides resorption of the cement could be seen. Histomorphometry proved, as well as biomechanical testing, no significant differences between the different groups. In the second part of the study x-ray examination showed an extensive resorption of the cement. Fluorescence microscopy certified the results of the first part of the study. CT-scans, microradiography and histology showed a complete filling of the defect with trabecular bone in the defects treated with autologous bone. In the untreated defect only a small part of newly formed bone was detectable. In the group treated with the cement, as well as in the group treated with the composite, great parts of the cement are resorbed and newly formed bone was detectable up to the middle of the defect. Like in the first part of the study there was a closed contact between cement and newly formed bone. Histomorphometry showed an ingrowth of bone in the empty defect of 5.1 % in relation to the whole defect. Defects treated with autologous bone graft were filled with 19.9 % bone, treated with TCP with 25 % newly formed bone and 11.3 % cement. The bFGF/TCP composite showed significantly less bony ingrowth with 15.7 % newly formed bone (p<0.05) and 14.4 % cement. Conclusion: The TCP-cement is resorbable and suitable for stable bone defects. The bFGF/TCP-composite had no effect in the first part of the study. The bone ingrowth and the biomechanical test showed no statistic significant difference. In the second part of the study bFGF showed an inhibitory effect on bone ingrowth into the bFGF/TCP-composite compared with TCP alone and autologous bone graft. Furthermore, bFGF seems to have negative effects on resorption of the TCP cement. Pure TCP showed more bone ingrowth than the autologous bone graft. In conclusion, addition of bFGF to this tricalcium phosphate cement has negative effects on bone formation and resorption of the cement, so it is not useful as bone replacement material. The good results of the pure TCP-cement show, that this cement is a good alternative for the filling of stable osseous defects.

Grantor dc:publisher

Publikationsserver der RWTH Aachen University

Year dc:date

2002

Author dc:creator

• Maus, Uwe Martin

Contributors dc:contributor

• Niethard, Fritz Uwe

• info:eu-repo/classification/ddc/610
• Medizin

Statement dc:rights

• info:eu-repo/semantics/openAccess

Language dc:language

ger

Identifier

https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-119200%22

OAI identifier oai:identifier

oai:publications.rwth-aachen.de:57132