Current aspects of alloplastic temporomandibular joint reconstruction

Since the advent of modern total alloplastic temporomandibular joint replacement systems (TMJ-TJR) which clinically offer favourable and stable long-term results, and with comparatively recently approved innovative systems, TMJ-TJR has once again become a principal focus of clinical interest. Although TMJ-TJR has traditionally been reserved for cases intractable to conservative and conventional surgical procedures, i.e. multiply operated and severely damaged TMJs (so-called "end-stage disease", or Wilkes stage V+), the range of clinical indications of TMJ-TJR has been continuously expanded. Previously, TMJ-TJR was considered a "last resort" for TMJ destruction as a part of temporomandibular disorders and for ankylosis. However, its present indications may suit rather earlier treatments, e.g. in the case of autoimmune diseases refractory to pharmacological therapy, as a reconstructive option for syndromic (e.g. Goldenhar syndrome) patients, or in the case of mandibular defects (e.g. after ablative oncological surgery, osteochemonecrosis, etc.). Subject to both well-balanced and well-established indications, as well as well-trained TMJ surgeons, TMJ-TJR can currently be considered an efficient and reliable tool, specifically for treating end-stage diseases. After being "hyped" over several years in the past, there is now a growing trend among TMJ surgeons urging for strict indications and a caveat to the use of TMJ-TJR as a "panacea". This narrative review delineates current aspects of TMJ-TJR based on evidence-based and consensus-based data (i.e. German S3 guideline, AWMF register number 007-106, 2020) with special interest placed on biomaterials, indications, contraindications, risks and complications.