TMJ

Question 1

What type of joint is the TMJ

Answer 1

Ginglymoarthrodial joint.

Question 2

The Superior compartment of the TMJ is involved in what type of movement?

Answer 2

Translational

Question 3

Rotational movement of the Condyle involves which compartment of the TMJ?

Answer 3

Inferior Compartment

Question 4

The mandibular condyle is formed by what type of bone formation?

Answer 4

Intramembranous Ossification.

Question 5

Most common site of bleeding in surgical approach to the TMJ Capsule?

Answer 5

Retrodiscal Tissue

Question 6

Describe the TMJ disc

Answer 6

Biconcave cross-sectional morphology.

Question 7

Which ligament limits posterior movement of the condyle?

Answer 7

Temporomandibular Ligament

Question 8

Which ligament limits excessive mouth opening?

Answer 8

Sphenomandibular ligament

Question 9

What is the main innervation of the TMJ?

Answer 9

Auriculotemporal nerve

Question 10

What is the Vascular Supply of the TMJ?

Answer 10

Anteiror: Superficial temporal and maxillary artery
Posterior: Masseteric artery

Question 11

What muscles are primarily involved in opening the mouth

Answer 11

Lateral Pterygoid, Digastric

Question 12

Which muscels are primarily involved in closing the mouth?

Answer 12

Masseter, Temporalis, Medial Pterygoid

Question 13

Which muscle(s) are primarily involved in protrusion of the mandible?

Answer 13

Anterior head of Temporalis

Question 14

Which muscle(s) are primarily involved in retrusion of the mandible?

Answer 14

Posterior head of Temporalis

Question 15

Name the Facial Layers to Access TMJ Capsule?

Answer 15

Skin,
SubQ,
SMAS/TP fascia,
Superficial layer of deep Temporalis fascia, Periosteum of zygomatic arch/ lateral capsule.

Question 16

Which layer is the Temporal branch of the Facial nerve?

Answer 16

Deep to TP fascia/SMAS

Question 17

What is the mean distance between the anterior border of the bony external auditory canal and the temporal branch of the Facial nerve?

Answer 17

0.8 to 3.5cm (Al-Kayat Study)

Question 18

How do you control excessive bleeding encountered when entering the TMJ joint space?

Answer 18

Most likely source is Retrodiscal tissues. Control bleending in by reseating the condyle in the fossa and maintaining pressure for several minutes. Or by using electrocautery.

Question 19

MRI T1 bright signal?

Answer 19

Fat

Question 20

MRI T2 bright signal?

Answer 20

Water

Question 21

Gallium-67 is best used for?

Answer 21

Osteomyelitis

Question 22

Technetium-99 is best used for?

Answer 22

Bone remodeling/ Growth activity

Question 23

Normal position of the disc on MRI closed mouth view?

Answer 23

Posterior band of disc at 11-12 o’clock position

Question 24

Normal position of the disc on MRI in open mouth view?

Answer 24

Intermediate zone interposed between condyle and articular eminence. Remains biconcave.

Question 25

When do you use a repositioning splint?

Answer 25

In patients when anterior mandibular positioning can recapture an anteriorly displaced disc. *Must be monitored carefully to prevent shifting of the dentition.

Question 26

Osteoarthritis is an Inflammatory arthritis or Noninflammatory arthritis?

Answer 26

Noninflammatory

Question 27

Contrast Osteoarthritis and Rheumatoid arthritis.

Answer 27

Osteoarthritis= Noninflammatory. Occurs Later in life- slow progression. No swelling. Single Joint Morning stiffness < 1hr. No Systemic Effects. Rheumatoid arthritis Rapid onset. Any time in life. 50% involve TMJ Painful + Swollen Symmetric/ Multiple joints >1hr Morning stiffness Systemic effects present.

Question 28

8yr Female with "bird face deformity" (Loss of height with class 2 malocclusion and apertognathia. What labs do you order?

Answer 28

Juvenile RA. Rheumatoid factor. ANA. ESR.

Question 29

Ankylosing Spondylitis is more prominent in Males or Females?

Answer 29

Males

Question 30

How many patients with psoriasis will also have arthritis?

Answer 30

One third of patients

Question 31

What is the clinical triad of Psoriatic arthritis?

Answer 31

Psoriasis Radiographic evidence of erosive arthritis Negative serology for RF.

Question 32

What serology will be positive for Ankylosing spondylitis?

Answer 32

HLA-B27 antigen RF will be negative.

Question 33

What is the clinical triad of Reiter Syndrome

Answer 33

Uveitis (can't see) Urethritis (can't pee Arthritis (can't climb a tree)

Question 34

What causes Reiter syndrome?

Answer 34

Intestinal infection (Salmonella, Shigella) Sexually transmitted infection (Chlamydia, Gonorrhea)

Question 35

3yr old boy presents with fever, rash, joint pain and swelling, and hepatosplenomegaly.

Answer 35

Still Disease. Subtype of JRA. Boys <5yrs Seronegative for RF, ANA.

Question 36

Monosodium urate monohydrate crystals=

Answer 36

Gout

Question 37

Calcium pyrophosphate dehydrate crystals=

Answer 37

Pseudogout

Question 38

Patient presents with Trismus, Deviation on opening, preauricular pain and swelling, pain in first metatarsophalangeal joint. Joint fluid aspirate shows needle shaped crystals with negative birefringence to polarized light microscopy.

Answer 38

gout

Question 39

What is the Etiology of Gout vs Pseudogout?

Answer 39

Overproduction or underexretion of uric acid = Gout Abnormally high concentration of inorganic pyrophosphate in synovial fluid= pseudogout.

Question 40

Risk factors for gout?

Answer 40

Purine-rich diet Diuretics Excessive alcohol Males> Females 40+

Question 41

Polarized light microscopy showing rhomboid shaped crystals with weakly positive birefringence.

Answer 41

Pseudogout.

Question 42

Treatment for Gout

Answer 42

Purine-low diet Colchicine Urate-lowering drugs (xanthine oxidase inhibitors, uricosuric drugs)