Diagnostic Classifications

Results from the TMD clinical examination can be used to determine the patient’s clinical diagnoses. The suggested diagnostic classification below provides a step-by-step approach that uses specific algorithms to determine a patient’s diagnoses.7 Only the most common diagnostic categories are provided.

Instructions:

  1. Diagnoses are not mutually exclusive, so TMD patients generally have multiple diagnoses.
  2. The term “altered” refers to either an aggravation or improvement, and “familiar pain” is the pain the patient is familiar with having.
  3. The parentheses ( ) around a number refers to a Clinical Examination item in Table 3.

Table 4. Diagnostic Classifications.7
Pain-related TMD Diagnoses
Myalgia:
Pain in temporalis or masseter muscle altered by jaw movement, function, or parafunction PLUS
Familiar pain when palpating either muscle (2) OR
Familiar pain during maximum unassisted or assisted opening (1).
Myofascial pain with referral, e.g., tooth pain from a masticatory muscle:
Referred pain altered by jaw movement, function, or parafunction PLUS
Familiar pain brought on when palpating the temporalis or masseter muscle (2).
Arthralgia:
Pain in preauricular region altered by jaw movement, function, or parafunction PLUS
Familiar pain when palpating the TMJ (2) OR
Familiar pain during maximum unassisted opening, assisted opening, or excursive movements (1).
TMJ Diagnoses
Disc displacement with reduction:
History of TMJ noise PLUS
Clicking or popping during opening and closing (4) OR
Clicking or popping during opening or closing and during excursive movements (4).
Disc displacement with reduction with intermittent locking:
History of TMJ noise and the TMJ locks causing a limited opening and then unlocks PLUS
Clicking or popping during opening and closing (4) OR
Clicking or popping during opening or closing and during excursive movements (4).
Disc displacement without reduction with limited opening:
The TMJ is locked causing a limited opening, in which the opening limitation is severe enough to interfere with eating PLUS
Maximum assisted opening is less than 40 mm (1).
Disc displacement without reduction without limited opening:
Previous history of the TMJ being locked with limited opening, in which the opening limitation was severe enough to interfere with eating PLUS
Maximum assisted opening is 40 mm or greater (1).
Degenerative joint disease:
History of TMJ noise PLUS
Crepitus present during maximum active opening, passive opening, or excursive movements (4).
Most TMD patients will have a myalgia diagnosis because pain is the most common reason patients seek care and pain from the muscles is more common than from the TMJ.  Disc displacement with reduction is fairly common, so many patients will also have co-occurring disc displacement with reduction.  Many patients will also have a portion of their pain from the TMJ, so many will also have an arthralgia diagnoses, in which the TMD is from both the myalgia and the arthralgia.  Hence, most TMD patients will have multiple TMD diagnoses.