Ongoing diagnostics and therapy of the craniomandibular and musculoskeletal system (TMS/MSS)
Autoren: Dr. Werner Schupp, Dr. Julia Steinmaier (geb. Funke), Dr. Wolfgang Boisserée
Introduction
Die Ruheposition des Kiefergelenks (TMJ), auch als „zentrische Relation“ bekannt, ist ein kontrovers diskutiertes Konzept, für das es bislang keine eindeutige Definition gibt. Nach aktuellem Verständnis befinden sich die Kondylen beidseitig in der anterosuperioren Position über dem Gelenkhöcker, während die Bänder der Kapsel maximal entspannt sind. In dieser Ruheposition ist die Muskelaktivität auf einem minimalen Niveau. Da diese Position von vielen Faktoren abhängt, ist eine exakte Definition schwierig. Besonders in pathologischen Situationen gestaltet sich die Bestimmung der Ruheposition als herausfordernd. Eine reversible Therapie mittels Aufbissschiene kann jedoch helfen, eine initiale Position für die Behandlung festzulegen.
Discussion of the centric relation of the temporomandibular joint
There is no universally valid definition for the centric relation. However, a clear definition of this physiological jaw relation is necessary for successful treatment. The position of the condyle can change daily within a small range, influenced by muscle tension, posture and psychological factors. Therefore, the main focus in the practice should be on finding an individually suitable condyle position.
The resting position of the temporomandibular joint
Despite intensive research, there are only a few reliable findings on the three-dimensional physiological position of the condyle in the fossa. Earlier methods usually analyzed this position using sagittal radiographs. The retral contact position (RCP) was often incorrectly equated with the centric position of the temporomandibular joint. This often led to incorrect treatments such as grinding in the teeth, which compressed and damaged joint structures. According to current knowledge, the ideal condylar position is in the anterosuperior position in relation to the eminentia articularis.
Determination of the jaw relation
There are various methods for recording the jaw relationship, but none has proven to be the only reliable one. Even digital measurement methods have not yet achieved the necessary precision. One common method is to create a jaw relation registration using wax plates. The patient is asked to bite into a heated wax plate while the practitioner checks whether the occlusion is even or whether there is a shift.
Therapeutic construction bite
The therapeutic construction bite helps to determine the resting position of the temporomandibular joint, especially in patients with pathologically altered joints. Precise palpation of the condyles at the external auditory canal enables an assessment of the tissue situation, movement patterns and joint symmetry. The therapist gently mobilizes the temporomandibular joint and guides the patient into a relaxed position. The aim should be to achieve an ideal overbite relation, which can later be transferred to a splint or definitive therapy.
Model assembly for occlusion analysis and fabrication of a COPA
A model is mounted with facebow transfer for precise analysis of the occlusion. After mounting the upper jaw model, the therapeutic bite registration is transferred to the lower jaw model. This precise recording is essential for diagnostics and the fabrication of an occlusal splint.
Clinical application: Patient case with severe TMD
A patient with severe back pain and anterior disc displacement of the temporomandibular joint was treated with a craniomandibular orthopaedic positioning appliance (COPA). The model analysis showed an unstable occlusion with only frontal contacts and an open bite in the posterior region. After five weeks of treatment with the COPA and accompanying physiotherapy, the patient was pain-free.
Conclusion
The diagnosis and treatment of TMD requires a precise assessment of the jaw relationship and a holistic view of the musculoskeletal system. The combination of manual therapy, splint therapy and modern orthodontics enables effective treatment. The therapeutically determined condylar position can be stabilized with aligner therapy or other orthodontic measures.
Source:
Schupp, W., Funke, J., & Boisserée, W. (2018). Continuing diagnostics and therapy of the temporomandibular and musculoskeletal system (TMS/MSS): The rest position of the temporomandibular joint (TMJ) and the therapeutic construction bite vs. the centric bite. Journal of Aligner Orthodontics, 2(4), 267-281.