EVALUATION OF SOFT-TISSUE REACTIONS AT THE INTERFACE OF TITANIUM LIMITED CONTACT DYNAMIC COMPRESSION PLATE IMPLANTS WITH DIFFERENT SURFACE TREATMENTS - AN EXPERIMENTAL SHEEP STUDY

Five types of limited contact dynamic compression plates (LC-DCPs) of pure titanium with different surface treatments and an electropolished stainless steel LC-DCP were tested. The surface roughness parameters and chemical surface conditions were determined and checked for probab le surface contamination. After an implantation period of 3 months on long bones of sheep, the soft tissue adjacent to the plates was evalua ted histomorphometrically. The difference in roughness parameters was statistically significant for most surface conditions. A correlation w as found between the surface roughness of the implants and the thickne ss of the adjacent soft tissue layer. The thinnest soft tissue reactio n layer with a good adhesion to the implant surface was observed for t he titanium anodized plates with coarse surface. Smooth implants, in p articular the electropolished stainless steel plates, induced statisti cally significant thicker soft tissue layers. Profilometer roughness m easurements combined with scanning electron microscopy techniques were useful methods to characterize the surface morphology.