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Chapter 8230hindrances that were encountered during the sheep interventions. The importance thereof became clear during the radiological analysis of the reconstructed enthesis, as 8 out of 13 cases did not show proper approximation of the bony enthesis against the implant scaffold.(16) Obviously contact osteogenesis could not occur in these 8 ewes without proper approximation of the enthesis. A second prerequisite that is necessary for contact repair, is the absence of motion. Pilliar et al.(45) found that in case of repetitive micromotions of 150µm or more, fibrous tissue is formed between the implant and the adjacent bone. Further research concluded that micromotions between the implant and the adjacent bone should be limited to 28 µm or less in order to promote osteogenesis.(45–48) In absence of this stability, successful osseointegration between the implant and its bony contact surface will be severely limited, with the risk of development of pseudoarthrosis.(49) While both the ramal and fossa component were properly fixated through the use of titanium screws, achieving similar stability in the LPM enthesis was far more difficult, as fixation of the LPM onto the scaffold was limited to a PDS 0 suture. Thus it is very likely that an insufficient amount of stability between the LPM and scaffold was obtained in our experiment, with repetitive micromotions of more than 150µm having occurred in the LPM reconstruction during both chewing and rumination. We believe this to be the reason why no osseointegration, yet rather fibrous integration, occurred in the five selected samples, despite the radiological bony contact that was observed.(16) In order to attempt to prevent micromovements on the level of the LPM in humans, a liquid diet and restriction of movement could be maintained during the first six postoperative weeks. It should be remarked however, that this could in turn delay or even limit the restauration of the maximal ‘range of motion’ during the post-operative recovery.(50)It should be remarked that, despite this the absence of osseointegration, a good approximation of the enthesis against the scaffold was achieved in all samples, with the formation of dense storiform to lamellar fibrous Nikolas de Meurechy NW.indd 230 05-06-2024 10:14