Disc Displacement without Reduction with Limited Opening
Stanimira I Kalaykova
A. Demographic Data and Reason for Contact
Caucasian female, 22 years old, jaw feels stuck, cannot open mouth completely.
B. Symptom History
Sudden onset of complaint 2 days ago.
Limited mouth opening interferes with biting off large pieces of food and mouth hygiene, especially in the molar area; no other interferences with activities and participation.
No pain, but an unpleasant pressing feeling in the right preauricular area.
Prior to onset of current complaint, a history of:
Clicking TMJ sounds on the right side, according to patient since approximately 3 years.
In the last 6 months, a few occurrences of short-lasting, intermittent locking on the right side that the patient could solve by herself by moving the jaw first to the contralateral side and afterward opening the mouth. On movement, an audible click would occur after which the jaw would open completely.
No other complaints from the masticatory system, except from the current complaint.
The patient visits her dentist twice per year.
Mouth hygiene consists of brushing twice per day and flossing.
No history of trauma.
The patient is aware of awake bruxism (jaw clenching).
C. Medical History
Review of systems is negative.
No allergies to medication; no seasonal allergies.
No routine medications.
No previous hospitalizations or surgeries; no emergency-room visits.
D. Psychosocial History
The patient is a medical student.
The patient shares a rental flat with two other students.
Average socio-economic status.
Active member of medical students’ association.
E. Previous Consultations and Treatments
No previous consultations and treatments regarding the current complaint.
F. Extraoral Status
No asymmetries with the jaw in rest position.
No swelling or redness.
No signs of neurologic deficit or somatosensory abnormalities.
Jaw movement capacity:
pain-free maximum mouth opening 24 mm;
active maximum mouth opening 25 mm with pressure feeling in the right preauricular area;
passive maximum mouth opening 26 mm with hard end-feel with pressure feeling in the right preauricular area;
protrusive movement 8 mm;
the jaw deviates toward the right side on mouth opening and protrusive movement;
laterotrusive movement toward the right side is 11 mm;
laterotrusive movement toward the left side is 6 mm.
No audible or palpable TMJ sounds on movement.
Manipulation by the clinician to allow reduction (unlock maneuver) is unsuccessful.
Palpation of TMJ: pain free.
Palpation of masticatory muscles: pain free.
Neck: normal range of motion, pain free.
G. Intraoral Status
linea alba present on inner aspect of cheeks right and left side;
gingiva and mucosa further in within normal limits.
Dentition and hard tissues:
full dentition, except for all wisdom teeth (18, 28, 38, and 48);
no dental restorations present;
slight tooth wear in enamel within normal limits;
Angle class I occlusion;
overjet and overbite of 2 mm.
H. Additional Examinations and Findings
Disc displacement without reduction with limited mouth opening in right TMJ.
J. Case Assessment
Patient with restricted mouth opening capacity where the clinical examination points to a reduced translatory movement in the right TMJ.
Anamnestic information reveals prior clickings in the right TMJ, intermittent lockings, and now no clickings but reduced mouth opening capacity; therefore, a very likely disc displacement without reduction.
No other significant problems with the masticatory system.
K. Evidence-based Treatment Plan including Aims
Treatment aims: restoration of oral function.
Counselling, explanation about TMJ disc displacement.
Mobilization aiming at gradual increase of condylar mobility and mouth opening.
Physiotherapeutic exercise therapy (“Minagi” exercise therapy, or mouth opening exercise (passive stretch) and horizontal movement exercises (active movements)) (see Background Information box).
L. Prognosis and Discussion
Good short-term prognosis since no TMJ pain is present on functional examination, no complicating factors in the patient’s medical history, no complicating psychosocial factors, and the patient’s young age.
In the long term, with persistence of displaced disc position, intraarticular degenerative or adaptive changes might occur but with no significant risk of clinical signs and symptoms.
A possible complication is development of arthralgia if too forceful mobilization is applied. The clinician should pay attention to pain response and the patient should carefully perform the mobilization exercises.
Definition, prevalence, and pathophysiology
DC/TMD defines disc displacement without reduction with limited mouth opening as “an intraarticular biomechanical disorder involving the condyle–disc complex.” In the closed mouth position, the disc is located in an anterior (and/or medial or lateral) position relative to the condylar head, and the disc does not reduce with opening of the mouth. The disorder is associated with persistent limited mandibular opening that does not reduce with the clinician or patient performing a manipulative maneuver.
Based on studies employing MRI, the prevalence of disc displacement without reduction is estimated to be 7–10%.
In the pathophysiology of the loss of TMJ reduction capacity, a combination of biomechanical factors (e.g., parafunctional load of the TMJ and hypermobility), anatomical, and tissue-specific factors (e.g., disc deformation, joint lubrication) might be involved.
Disc displacement with reduction with intermittent lockings has a high risk of developing into a disc displacement without reduction.
(Kalaykova et al., 2011; Naeije et al., 2013; Schiffman et al., 2014)
Physiotherapeutic exercise management
“Minagi” exercise therapy
Place the thumb on the left maxillary canine and the forefinger on the right mandibular canine. Make maximal lateral gliding jaw movements to the left. Support the movements with the fingers. Make maximal jaw opening movements through the lateral border path on the left side.
Mouth opening exercise (passive stretch)
Open the mouth as wide as you can. Place the thumbs of both hands on the maxillary anterior teeth and the forefingers on the mandibular anterior teeth. Stretch the fingers, thereby slightly increasing the mouth opening. Afterwards, hold the mouth opening for 10 s. Repeat the exercises for 10 times. When stretching you may feel slight discomfort. In case you feel pain, please decrease the applied force.
Horizontal movement exercises (active movements)
Bring the jaw as far as you can to the left; repeat 10 times. Bring the jaw as far as you can to the right; repeat 10 times. Bring the jaw as far as you can to the front; repeat 10 times.