Osseointegration of dental implants in early regenerate bone produced by bone transport distraction osteogenesis

The purpose of this study was to evaluate the differences in structure between native canine mandibular bone and that of early regenerated bone, and to compare the osseointegration of dental implants placed in native canine mandibular bone to those placed in early regenerated bone, produced by bone transport distraction osteogenesis. Further, this study aimed to explore the accuracy of mu-CT technology when used to detect mineralized tissue in 3D around dental implants.;Ten adult foxhounds were divided into two groups of 5 animals each. In all animals, a 35-40 mm defect was created on one side of the mandible. A bone transport reconstruction plate was used to stabilize the mandible and regenerated bone. Six weeks after the distraction period was finished, dental implants were placed in regenerated and native mandibular bone. The animals were sacrificed after another six and twelve weeks of healing respectively.;Bone was successfully regenerated in all of the animals. Regenerated bone is still mineralizing and native bone appears denser because of a thick outer layer of cortical bone that is not yet formed in the regenerate. However, the regenerate showed a significantly higher number of thicker trabeculae that contribute to its biomechanical ability to function under the variable loads of mastication. The implants placed entirely in regenerated bone were osseointegrated. The regenerated bone around the implants becomes denser as healing time increases. This finding suggests implants placed entirely in regenerated bone are as well integrated as those in native mandibular bone by twelve weeks after placement.;Finally, the mu-CT analysis gives a limited 3D representation of the mineralized tissue around dental implants. The estimation of BV/TV decreased significantly closer to the implant surface because of the presence of x-ray beam artifact. High correlations were found with the 2D measurements of mineralized tissue between mu-CT and histology at 30mum distance from the implant surface.