Experimental Study Of The Biomechanics And Related Research In The Surface Of A New Type Prosthesis (Titanium-Sponge Sinterring)

Objective To study on the method of combining rhBMP2 with Titanium -Sponge Sinterring implants (TiSS),and compared the histological and biomechanical results of 4 types of implants by being inserted into the femur of canine. Methods4 types of implants which are Titanium — Sponge Sinterring(TiSS) +BMP +NB (Nano-HA/Collagen/PLA Composite bone ) ., porous coated implants ( PCA) ,TiSS implants combined with BMP.. PCA with hydroxyapatite and HA coatedcylindrical implants had been inserted into the femur of 16 rates . After 4 , 8 and 12 weeks the femur of the canines with the implants were retrieved Bone ingrowth and shear strength of the interface was studied and analysed by the means of X-ray , soft X-ray , fluorescence tag , non-decalcification bone ground section , computer aided image analysis procedure and biomechanical test. Results X-ray , soft X-ray , fluorescence tag , non-decalcification bone ground section and computer aided image analysis procedure was used in histological study , and it showed that bony ingrowth into interface more than the other groups , even the maturation of newly formed bone Non-decalcification bone ground section observation and computer aided .there was significant difference between (TiSS) +BMP +NB group and each of the other group statistically( P < 0.05) .Results of biomechanical study using push out test showed that shear strength of each group appeared to rise with time and there was also statistical difference between (TiSS) +BMP +NB group and each of the other group ( P < 0105) And the new bone formation ratio and shear strength of (TiSS) +BMP +NB group at 4 ,8 ,12 weeks post-implantation was still higher than the other group . Conclusions Porous-coated implants combined with(TiSS) +BMP +NB can enhance bone ingrowth at bone-implant interface especially at the early period post-implantati on Porous-coated implants combined with (TiSS) +BMP +NB can not only shorten the time of new bone formation and bone ingrowth but also enhance shear strength ofbone-implant interface.Part 2Unsaturated polyphosphoester(UPPE) containing unsaturated double bonds in main chain was synthesized with Fumaric acid, 1,2-propylene glycol and phosphorous oxychloride as the initiation materials. Three kinds of isomers of bis(l,2-propyleneglycol) fumarate were detected in main chain of UPPE by FTIR and NMR. The effect of reaction time on condensation polymerization reaction was investigated with GPC. High and uniform molecular weight polymer can be obtained by extending poly reaction time. The molecular weight is 5956g.mol-l and the poly dispersion degree is 1.12 after refiuxing for 18 hours. The temperature curve of UPPE crosslinked with l-vinyl-2- pyrroljdone indicated that the maximum temperature isfrom 51.0°C to 63.6°C, and the setting time is between 6.37 minutes and 7.85 minutes.Part 3To observe and analyze the characteristics and mechanism of the bone regeneration guided by the complex of PPE and PPF .Twenty-four rabbit withbilateral radius bone defect were divided into three groups : A^ B and C. In the rightside, the defect was covered with the PPE/ calcium phosphate ^ PPF/ and calciumphosphate the calcium phosphate. The left defect was covered nothing and regarded as control. The rats were killed at the 4nd, 8th, 12th, 16th week. Samples were treatedfor radiological and histological studies. In the experimental sides the bone defects were healed. New bone appeared in the way of intramembranous ossification and entochondrostosis. The complex of PPE and PPF has the effects on preventing from nonunion. In the speed and quality of bone regeneration.