Long-term Safety and Performance of Materialise's Patient-specific TMJ System.

The study begins with patient inclusion and pre-operative examination, where eligibility is assessed based on inclusion and exclusion criteria. Informed consent is obtained, and if a participant drops out before implantation, a new patient is enrolled. Pre-operative assessments include (CB)CT imaging, collection of demographic details, medical history, and co-morbidities using the Charlson Comorbidity Index (CCI). Other pre-operative evaluations include maximal inter-incisal opening (MIO), occlusion, diet consistency, and several questionnaires to assess quality of life, jaw function, and speech. Pre-operative (CB)CT scans are used for surgical planning and device design.

During surgery and hospital stay, the index procedure marks the patient's enrollment. Surgical details are documented, including the approach, device characteristics, operation time, and complications. Intraoperative adverse events, such as allergic reactions or hematoma, are recorded. A post-operative (CB)CT scan is performed within a week, and patient and surgeon satisfaction, both functional and aesthetic, are recorded. Any post-operative complications are tracked.

For follow-up, the study includes 9 follow-up visits at intervals of 1 week, 4 weeks, 3 months, 6 months, 1 year, 2 years, 3 years, 5 years, and 10 years. At each visit, MIO, occlusion, diet consistency, and jaw function are assessed, and patients complete the EQ-5D-5L, OHIP-14, and Helkimo Clinical Dysfunction Index questionnaires. A (CB)CT scan is performed at specific follow-ups, and any post-operative complications, adverse events, or re-interventions are reported. Medication intake is recorded as well.

• Safety endpoint: Occurrence rate of periprosthetic infection [Time frame: From implantation up to 10-year follow-up, with evaluations at Week 1, Week 4, Month 3, Month 6, Year 1, Year 2, Year 3, Year 5, and Year 10, or until device removal or re-intervention due to implant-related or non-implant-related complications.]
• Radiological Parameter Endpoint: Presence of Ectopic Bone [Time frame: From implantation through 10-year follow-up, with (CB)CT scans performed at Week 1, Week 4, Year 1, Year 3, Year 5, and Year 10, or until device removal.]
• Performance Endpoint: Mean Interincisal Opening (MIO) [Time frame: From baseline (pre-implantation) through 10-year follow-up post-implantation, with evaluations at baseline, discharge, Week 1, Week 4, Month 3, Month 6, Year 1, Year 2, Year 3, Year 5, and Year 10, or until device removal.]
• The relationship between the device's success rate and the underlying medical condition [Time frame: Up to 10-year follow-up post-implantation, with evaluations at Week 1, Week 4, Month 3, Month 6, Year 1, Year 2, Year 3, Year 5, and Year 10, or until device removal due to mechanical or biological failure, stratified by underlying medical condition]
• Mean implantation time [Time frame: From implantation until device removal or up to 10-year follow-up post-implantation.]
• Surgical operation time [Time frame: At procedure (intraoperative).]
• Total hospital post-operative stay [Time frame: From surgery completion untill discharge date, when the patient is deemed clinically stable and released from hospital care, assessed up to 30 days post-operatively, with the duration varying based on underlying conditions and recovery progress.]
• Perioperative complications [Time frame: The perioperative period, encompassing the pre-operative (before surgery), intra-operative (during surgery), and post-operative (after surgery) phases, from patient admission for surgery until discharge home.]
• Intraoperative blood loss (mL) [Time frame: At procedure (intraoperative)]
• Technical success of the implantation [Time frame: At procedure (intraoperative), and at first post-operative imaging (CB)CT at Week 1 for comparison with the pre-operative plan.]
• Radiological Parameter Endpoint: Displacement of Ramus Component [Time frame: From implantation through 10-year follow-up, with (CB)CT scans performed at Week 1, Week 4, Year 1, Year 3, Year 5, and Year 10, or until device removal.]
• Safety endpoint: Occurrence rate of weakness of the temporal branch of the facial nerve [Time frame: From implantation up to 10-year follow-up, with evaluations at Week 1, Week 4, Month 3, Month 6, Year 1, Year 2, Year 3, Year 5, and Year 10, or until device removal or re-intervention due to implant-related or non-implant-related complications.]