Introduction
Before any prosthesis, the clinician has to know how well the masticatory system works and whether it has a disorder. Diagnosis means telling one disease from another: first, whether the complaints come from a temporomandibular disorder (TMD) at all, then which kind.
Clinical functional examination
It starts with a questionnaire and history, then examines active movements (the patient moves), passive movements (the examiner moves the jaw), traction and translation of the mandible, compression of the joints and resistance tests. The main clinical tool is palpation of muscles and joints.
Six orthopedic tests
To make the diagnosis reliable between examiners, six groups of tests are used:
Gnathodynamometry
A gnathodynamometer measures the biting force between upper and lower teeth. The patient bites on a sensor with an adjustable central bearing point, at the incisors or at the molars. It shows the maximum bite force and, compared with normal values or the other side, how much chewing power the patient has lost.