temperomandibular dysfunction

Question 1

what are accessory muscles of mastication?

Answer 1

• Suprahyoid muscles
  Digastric
  Mylohyoid
  Geniohyoid
  Stylohyoid
• Infrahyoid muscles
  Thyrohyoid
  Sternohyoid
  Omohyoid
  Sternothyroid

Question 2

what are causes of TMD?

Answer 2

Myofascial pain

Disc displacement
Anterior with reduction
Anterior without reduction

Degenerative disease (not as common)
Localised – osteoarthritis
Generalized (Systemic) – rheumatoid arthritis

Chronic recurrent dislocation

Ankylosis - rare cause

Hyperplasia

Neoplasia (osteochondroma, osteoma, or sarcoma (malignant)) - rare

Infection

Question 3

difference between anterior with reduction and without reduction?

Answer 3

with reduction is when disc slips out but can slip back to it’s proper place

Question 4

what are pathogeneis of tmd?

Answer 4

Inflammation of muscles of mastication or TMJ secondary to parafunctional habits

Trauma, either directly to the joint or indirectly e.g. sustained opening during dental treatment

Stress

Psychogenic

Question 5

what is important to spend extra time on during exam?

Answer 5

social history - stress, occupation, sleep etc

Question 6

what is crepitus?

Answer 6

• crunchy sound that is normally an indication of arthritic change

Question 7

on examination what is important to exam intra and extra orally?

Answer 7

E/O
Muscles of mastication
Joints
Clicks – early/late
Crepitus
Jaw movements
Facial asymmetry

I/O
Interincisal mouth opening
Signs of parafunctional habits
Cheek biting (morsicatio buccarum)
Linea alba
Tongue scalloping
Occlusal non-carious tooth surface loss
Muscles of mastication

Question 8

what are common clinical features of tmd?

Answer 8

Females > males

Age: most common between 18-30 years

Intermittent pain of several months or years duration

Muscle / joint / ear pain, particularly on wakening

Trismus / locking

‘Clicking/popping’ joint noises

Headaches

Crepitus indicates late degenerative changes

Question 9

what are differential diagnosis of tmd?

Answer 9

Dental pain

Sinusitis

Ear pathology

Salivary gland pathology - more suspicious if tmd only one side

Referred neck pain

Headache

Atypical facial pain

Trigeminal neuralgia

Angina

Condylar fracture

Temporal arteritis

Question 10

what is treatment of tmd?
- patient education?

Answer 10

Reversible
- Patient education
Counselling
Electromyographic recording
Jaw exercises
Physiotherapy

Question 11

what is treatment of tmd?
- medication?

Answer 11

• Medication
  NSAIDs
  Muscle relaxants
  Tricyclic antidepressants
  Botox - reducing clenching not first line of attack
  Steroids

Question 12

what is treatment of tmd?
- physical therapy?

Answer 12

• Physical therapy
  Physiotherapy
  Massage/heat
  Acupuncture
  Relaxation
  Ultrasound therapy
  TENS (Transcutaneous Electronic Nerve Stimulation)
  Hypnotherapy

Question 13

what is treatment of tmd?
-splints?

Answer 13

• Splints
  Bite raising appliances
  Anterior repositioning splint

Question 14

what is counselling you’d give for tmd?

Answer 14

Reassurance

Soft diet

Masticate bilaterally

No wide opening

No chewing gum

Don’t incise foods

Cut food into small pieces

Stop parafunctional habits e.g. nail biting, grinding

Support mouth on opening e.g. yawning

Question 15

what is anterior disc displacement with reduction signs/symptom?

Answer 15

Signs/symptoms
- jaw tightness/locking i.e. jaw movement is impaired for a short period of time until the disc reduces
- The mandible may initially deviate to the affected side before returning to the midline.

If left untreated, may eventually progress to osteoarthritis

Question 16

what is anterior disc displacement with reduction treatment?

Answer 16

Treatment
- Counselling
- Limit mouth opening
- Bite raising appliance
- Surgery occasionally may be required

If painless, no treatment required
- Reassure

Question 17

what splint is this?

Answer 17

anterior repositioning splint

Question 18

what splint is this?

Answer 18

wenvac splint

Question 19

what is treatment for irreverisible tmd?

Answer 19

• Occlusal adjustment
  Rarely done – no evidence of benefit1
• TMJ surgery
  Arthrocentesis
  Arthroscopy
  Disc-repositioning surgery
  Disc repair/removal
  High condylar shave
  Total joint replacement

Question 20

how does disc displacement come about?

Answer 20

• Joint clicking is due to lack of coordinated movement between the condyle and the articular disc
• The condyle has to overcome the mechanical obstruction before full joint movement can be achieved.
• Clicks may occur on opening or closing and can be classified as early, middle or late

Question 21

what is anterior disc displacement with reduction?

Answer 21

The most common cause of TMJ clicking

Disc is initially displaced anteriorly by the condyle during opening until disc reduction occurs

Question 22

what are some causes of trismus from trauma and what to do if no resolution after acute phase?

Answer 22

IDB
Prolonged dental treatment
Infection
- all should usually resolve spontaenously

If no resolution after acute phase:
Physiotherapy
Therabite®
Jaw screw