Tel.+49 30 838 62450 Fax.+49 30 838 62522
The aim of this study, as a part of a project to test the effect of growth hormone on distraction osteogenesis in minipigs, was to compare the amount of pintractinfection in different biornaterials (titan and RFGD-silicone) in the different locations proximal and distal. A clinical score and daily body temperature measurements were tools for the clinical examination.The body temperature of the animals during the study varied very much. In the daily clinical examination of the pintracts it became obvious that the distal pins had less infections than the proximal pins.The implanted material and the surrounding tissue was histologically analysed, to investigate the growth of keratinocytes and their adhesion to the biomaterial.23 2 pins were implanted into the left lower leg of the minipigs. 76 pins had to be reimplanted because of pintractinfection. The clinical pintractinfection can also be seen in the mean of total score of each animal which is 59,1.At the end of the study (26 days) we found another 104 clinical pintractinfection, 26 noninfected siliconepins and 26 noninfected titanpins were examined histologically and morphometrically. Thus all the examined pintracts were clinically without any signs of infection, we had histologically signs of infection in each preparation. We also found growth of keratinocytes in each preparation.The postulated grow on of the keratinocytes at the percutaneous device did not occur. In five preparations a adhesion of the cells could be diagnosed (2x KT, 3x RS). In comparison of the two biomaterial surfaces there were little differences. There is slightly more tendency of keratinocyte adhesion in the RFGD-silicone.It became evident that the pins that were located distally at the limb had less infections, we could examine 3 2 pintracts of distal locations and only 20 pintracts of proximal location. The growth of keratinocytes in the distal locations was higher than in proximal locations (distal mean: 2,61 mm, proximal mean: 1,6). Four of the pins with adhesion of keratinocytes at the biomaterial were located distally and only one proximally.We compared the pinscores of the two locations to one another and found that the distal located pins had lower pinscores, that means less pintractinfection (distal median 34,0, proximal median 43,1). The comparison of the pinscores split by the biomaterials titan and RFGDsilicone showed that RFGD-silicone had higher scores (median: RFGD-silicone 46,0, titan31,0).