The general objective of this observational study is to clarify the clinical, microbial, and tissue characteristics, aetiology, and risk factors behind severe TMJ pathology. The main questions it aims to answer are:
* What are the clinical and histologic characteristics of patients with severe pathology of the TMJ? * Can microbial DNA be found in TMJ tissue from patients with severe pathology of the TMJ, and if so, does this correlate to the outcome of the surgery?
Patients subjected to open TMJ surgery such as arthroplastic surgery with or without autogen or allogen reconstruction
Preserved biobank material (resected bone and soft tissue).
Absence of biobank material.
Inability to give informed consent.