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Chapter 13350important to note that in one case, the post-mortem dissection was poorly executed, resulting in the loss of the LPM enthesis. In two other samples, the bony enthesis was not retained yet instead the fibrocartilaginous enthesis was fixated onto the scaffold. Three sheep showed a purely fibrous tissue connection between the bony enthesis and the condylar scaffold. Again, in one sheep, the fibrocartilaginous enthesis was reinserted rather than the bony enthesis. Three sheep displayed both a partial bony and partial soft tissue reattachment. The total thickness of this soft tissue attachment was with an average thickness of 0.4mm markable thinner compared to the specimen that only showed a soft tissue connection. Lastly, two sheep showed a uniquely bony ingrowth of the enthesis into the scaffold. Interestingly, in one of these samples, only the fibrocartilaginous enthesis was preserved and reattached. The five specimens with a (partial) bony reattachment of the LPM were selected for further histological analysis. Despite our radiological findings, in only two samples an actual boney extension, albeit limited, into the condylar scaffold was objectified. These samples revealed several vital, isolated, bony islands within the scaffold, with the presence of osteocytes and active remodeling. However, these bony islands were not in contact with the bony LPM enthesis in the section plane that was analyzed. All samples had developed dense, storiform collagen within the scaffold, as well as a thin lamellar layer of collagenous tissue between the implant and the bone, ranging from 20 to 150µm, except for one sample where a maximal thickness of 500µm was found. The enthesis itself were found to be viable in all samples with active bone remodeling which was most apparent near the implant scaffold site. Despite this bone remodeling, no or very limited ingrowth into the scaffold was seen.For osseointegration to be possible, a good osteoconductive, -inductive and biocompatible environment needs to be provided. The implant and scaffold surfaces need to be sufficiently osteoconductive to stimulate bone cell growth. The environment also needs to be osteoinductive to promote differentiation of mesenchymal stem cells (MSCs) into (pre)osteoblasts. Good osteogenesis also must also be achieved (i.e., sufficient MSCs, osteoblasts, and osteocytes need to be present). As discussed previously, both the material choice and surface modifications aimed to achieve and improve upon both osteoconductivity and -inductivity. We concluded this Nikolas de Meurechy NW.indd 350 10-06-2024 11:12