Page 354 - Demo

Chapter 13352Although no osseous ingrowth was found, clinical, radiological, as well as the histological analysis of the treated sheep and the selected samples revealed that the specific scaffold design allowed for the enthesis of the lateral pterygoid muscle to produce a strong and functional fibrous reattachment to the implant, allowing for lateral mandibular movement, thus improving functionality compared to currently available TMJR.In vivo analysis – Implant integration Besides the reattachment of the LPM, both the condylar and fossa components were also radiologically evaluated for proper integration. All condylar components revealed good radiological integration. In addition, 2 ramal components were histologically evaluated, revealing bony ingrowth into the porous structure. In both samples, a multitude of haversian canals and osteocytes, with bone remodeling was seen, indicating viable osseous tissue and thus a successful osteointegration of the ramal component. As stated earlier, a latero-inferior displacement of the fossa component was seen in 3 sheep. We hypothesized this was due to the use of 2mm diameter fixation screws for the fossa component, as determined for human subjects, despite the fossa being subjected to more laterotrusive movement. This might have led to excessive stress in the bone surrounding the screws, with gradual bone resorption and thus micromovement of the fossa component, resulting in this displacement.(96–98) Nevertheless, the bearing surface as well as function of the TMJ remained intact in these sheep. One sheep showed a slight infero-dorsal displacement, yet the fixation screws remained intact, thus this displacement is likely due to improper placement and fixation.Clinical application and future considerationsFollowing the successful animal trail, 11 patients and 16 joints were treated with a ‘regular’ custom designed TMJR. Five patients, equaling six TMJ were treated with an ‘extended’ TMJR (eTMJR). As stated earlier, the use of a custom designed TMJR allows for several additional corrections to be ‘worked into’ the prosthesis, thus preventing the need for additional surgery.(68,71,72) Whilst little difficulties were encountered in the first Nikolas de Meurechy NW.indd 352 10-06-2024 11:12