Résumé
BACKGROUND:Zinc-modified calcium silicate (CaSiO3) bioceramics coating on the titanium surface prepared in preliminary experiments has good chemical stability and antibacterial property. OBJECTIVE:To observe the effects of zinc-modified CaSiO3 bioceramics coating on osteointegration. METHODS:MC3T3-E1 cels were respectively cultured on the titanium with zinc-modified CaSiO3 bioceramics coating (experiment group), titanium with CaSiO3 bioceramics coating (control group) and pure titanium (blank control group). Then, cel adhesion, proliferation, calcification rate and the expression of type I colagen and osteocalcin were detected. The implant materials mentioned above were respectively inserted into the femurs of New Zealand white rabbits, and after 1.5 months, the osteoproliferation and osteointegration between the implants and the host were tested. RESULTS AND CONCLUSION:In vitro experiment: The number of adhesive cels at 12 hours after co-culture was significantly increased in the experimental group compared with the control group and blank control group (P < 0.05). At 14 days after co-culture, cel proliferation ability and ability of calcium nodule formation in the experiment group were significantly better than those in the other groups (P < 0.05). At 21 days after co-culture, there was no significant difference in the expression of type I colagen, but the expression of osteocalcin in the experiment group was higher than that in the control group and blank control group (P < 0.05).In vivo experiment: In the experiment group, a large amount of bone substances were detected, the coating materials directly contacted with the bone interface, new bone tissues and little fibrous tissues were observed at the interface. In contrast, there was a small amount of bone hyperplasia in the control group and almost no bone hyperplase in the blank control group. Moreover, a small part of the implant directly contacted with the bone interface and the most part was separated from bone trabeculae by fibrous tissues. These findings indicate that zinc-modified CaSiO3 bioceramics coating can enhance the ability of osteointegration between titanium implants and the host.
Résumé
OBJECTIVE: Injuries and pathological changes of hard tissue(bone, tooth,etc.) are common clinical affairs. If the injuries or pathological changes are too serious to be treated with medication, they should be repaired or replaced by hard tissue replacement implants. Researches of hard tissue replacement implants have become an important research direction in biomaterial field at present. This paper is aimed to summarize the type, mechanical feature and biological properties of human hard tissue replacement implants for the indication of the direction in its development.STUDY SOURCES: Time of the search was from January 1998 to July 2004. Search range: 30 types of periodicals from CNKI digital library (Chinese Periodical Full Text database) and Science Direct digital library. Search words were hard tissue replacement implants, artificial bone,artificial root of tooth, bioceramic, and biological coat, etc. Search methods included electronic search and manual search, etc.STUDY SELECTION: Totally 200 corresponding literatures on human hard tissue replacement implants were selected for analysing and summarizing.DATA EXTRACTION: To summarize the corresponding information in the obtained research articles regarding hard tissue replacement implant.DATA SYNTHESIS: To comparatively analyze the mechanical and biological properties of each hard tissue replacement implant as well as their effects in practical application. The existing hard tissue replacement implants including metal materials, macromolecular materials, ceramics and their composite materials have been widely applied in clinics; however, their mechanical and biological properties have not been perfectly combined.CONCLUSION: It is always a key point(key point in researches) in biomedical material academia to find a replacement implant, of which the mechanical and biological properties perfectly suitable for the human hard tissues. The new generation of hard tissue replacement implants established by the application of biomimetic process, nano-technology, composite materisls and tissue engineering could hopefully satisfy the increasingly elevated demand of human beings.