Lec 5

Question 1

You need this before you can attribute a headache to TMD.

Answer 1

Primary TMD diagnosis

Question 2

In a normal disc position, in the sagittal plane, relative to the superior aspect of the condyle, the border between the low signal of the disc and the high signal of the retrodiscal tissue is located between which clock positions?

Answer 2

11:30 and 12:30

Question 3

For a normal disc, in the sagittal plane, the intermediate zone is located between what?

Answer 3

The anterior-superior aspect of the condyle and the posterior-inferior aspect of the articular eminence.

Question 4

Describe the position of the posterior band on the condyle when the mouth is closed.

Answer 4

Should be POSTERIOR to the 11:30 position.

Should NOT be anterior to the 11:30 position.

Question 5

Location of the intermediate zone in disc displacement.

Answer 5

ANTERIOR to the superior part of the condyle.

Question 6

What does the posterior band look like on an MRI?

Answer 6

Where the white and gray parts meet at the line.

Posterior band is WHITE on an MRI.

Question 7

Diagnose the disc displacement:

In the closed mouth position, the disc is in an anterior position relative to the condylar head and the disc reduces upon opening of the mouth.
Medial and lateral displacement of the disc may also be present.
Clicking, popping, or snapping noises may occur with disc reduction.
A hx of prior locking in the closed mouth position coupled with interference in mastication precludes this dx.

Answer 7

Disc displacement with reduction.

Question 8

Hx in disc displacement with reduction.

Answer 8

Hx of joint sounds

Question 9

Dx:
1 click on opening, or 1 click on closing.
1 click in opening; 1 in closing, +1 click in lateral protrusive movements.

2 vertical clicks, or 1 vertical and 1 horizontal click

Answer 9

Disc displacement with reduction.

Question 10

Dx:
In the MRI:
1) In the maximum intercuspal position, the posterior band of the disc is anterior to the 11:30 position and the intermediate zone of the disc is anterior to the condylar head; AND

2) On full opening, the intermediate zone of the disc is located between the condylar head and the articular eminence.

Answer 10

Disc displacement with reduction.

Question 11

Only this can diagnose a lateral or medially displaced disc.

Answer 11

MRI

Question 12

Dx:
In the closed mouth position, the disc is in an anterior position relative to the condylar head, and the disc intermittently reduces with opening of the mouth.

When the disc does not reduce with opening of the mouth, intermittent limited mandibular opening occurs.

When limited opening occurs, a maneuver may be needed to unlock the TMJ.
Medial and lateral displacement of the disc may also be present.

Clicking, popping, or snapping noises may occur with disc reduction.

Answer 12

Disc displacement with reduction with intermittent locking.

Question 13

When does a jaw lock?

Answer 13

When the disc does NOT reduce when you open the mouth.

Question 14

Hx for disc displacement with reduction with intermittent locking.

Answer 14

Jaw locks with limited opening, even for a moment, and then unlocks.

Question 15

If there’s no sounds, then there’s no what?

Answer 15

Reduction

Question 16

Limited opening means maximum assisted opening is less than how many mm?

Answer 16

40

Question 17

Closed lock

Answer 17

When you can’t open your mouth all the way.

Question 18

Open lock

Answer 18

When you can’t close your mouth all the way.

Question 19

Dx:
History of:

1) Locked jaw so that the mouth cannot open all the way AND
2) Limitation in jaw opening severe enough to limit jaw opening and interfere with ability to eat.

Answer 19

Disc displacement WITHOUT reduction with limited opening.

Question 20

T/F:

You know there’s NO reduction when the posterior band is anterior to the 11:30 position when the mouth is OPEN.

Answer 20

TRUE

Question 21

Dx:

In the closed mouth position, the disc is in an anterior position relative to the condylar head and the disc does not reduce with opening of the mouth. Medial and lateral displacement of the disc may also be present. This disorder is NOT associated with current limited opening.

Exam:

Maximum assisted opening movement including vertical incisal overlap is greater than or equal to 40 mm.

Answer 21

Disc displacement without reduction without limited opening

Question 22

Can you have TMJ noise (clicking during opening) in disc displacement without reduction?

Answer 22

Yes

Question 23

Clicks during what movement are needed for reduction?

Answer 23

During opening and closing, or one opening/closing and one horizontal movement.

Question 24

For degenerative joint disease, we use this machine.

Answer 24

CT

Question 25

Useful for assessing osseous deformities, but CANNOT produce accurate images of the articular disc.

Answer 25

CT

Question 26

Dx: 1) Normal relative size of the condylar head. 2) No subcortical sclerosis or articular surface flattening. 3) No deformation due to subcortical cyst, surface erosion, osteophyte, or generalized sclerosis.

Answer 26

Normal Joint/condyle

Question 27

The condyle or eminence have bone changes in this.

Answer 27

Degenerative Joint Disease

Question 28

Continuous crunching sound.

Answer 28

Crepitus

Question 29

Hx for what disease? 1) In the last 30 days, any TMJ noises with jaw movement or function. OR 2) Pt reports of any noise during the exam.

Answer 29

Degenerative Joint Disease

Question 30

Exam for what disease? Crepitus detected with palpation during any movement.

Answer 30

Degenerative Joint Disease

Question 31

These findings do NOT mean that you have Degenerative Joint Disease

Answer 31

Flattening or cortical sclerosis

Question 32

These imaging findings indicate you have Degenerative Joint Disease.

Answer 32

- Subchondral cysts - Erosion - Generalized sclerosis - Osteophytes

Question 33

What is loss of cortical bone, like someone is chewing it?

Answer 33

Erosion

Question 34

What does generalized sclerosis look like on a CT scan?

Answer 34

The condyle is completely white.

Question 35

When the jaw is locked open (can't close), and the patient has to self-maneuver it to reduce the dislocation.

Answer 35

Subluxation.

Question 36

When the patient has an open lock, and needs a doctor to put it back into position.

Answer 36

Luxation

Question 37

Luxation and Subluxation are AKA

Answer 37

Open lock

Question 38

Dx: In the open mouth position, the disc-condyle complex is positioned anterior to the articular eminence and is unable to return to a normal closed mouth position without a manipulative maneuver. When the patient can reduce the dislocation himself/herself, this is called what?

Answer 38

Subluxation

Question 39

What does CT imaging for subluxation show?

Answer 39

The condyle is positioned anterior to the articular eminence with the patient unable to close his/her mouth.

Question 40

Most frequent cause of TMJ ankylosis is this?

Answer 40

Macrotrauma

Question 41

These are characterized by restricted mandibular movement with deflection to the affected side on opening that may result as a long-term sequela of trauma, including mandibular fracture.

Answer 41

Intra-articular fibrous adhesions and ankyloses.

Question 42

The formation of a bony mass that results in fusion of the joint compartments.

Answer 42

Osseous ankylosis

Question 43

Fibrous adhesions of the TMJ that cause hypomobility occur in which compartment?

Answer 43

Superior

Question 44

Marked deflection to the affected side is seen in what kind of disorders?

Answer 44

Hypomobility

Question 45

Most common ankylosis

Answer 45

Fibrous

Question 46

This type of ankylosis has no radiographic finding other than the absence of ipsilateral condylar translation on opening.

Answer 46

Fibrous ankylosis

Question 47

Has radiographic evidence of bone proliferation with deflection to the affected side and limited laterotrusion to the contralateral side.

Answer 47

Osseous ankylosis

Question 48

Must have the following to diagnose what kind of ankylosis? 1) Limited range of motion on opening. 2) Marked deflection to the affected side. 3) Markedly limited laterotrusion to the contralateral side. 4) No radiographic evidence. 5) Decreased to complete lack of ipsilateral condylar translation on opening. 6) A disc space between the ipsilateral condyle and the eminence.

Answer 48

Fibrous Anklyosis

Question 49

Disc space difference btw fibrous and osseous ankylosis.

Answer 49

No disc space in osseous ankylosis bc it's replaced with bone.

Question 50

In this ankylosis, imaging must show bone proliferation with obliteration of part or all of the joint space.

Answer 50

Osseous

Question 51

Increase in the normal number of cells (non-neoplastic)

Answer 51

Hyperplasia

Question 52

Incomplete or underdevelopment of the cranial bones or mandible.

Answer 52

Hypoplasia

Question 53

Unilateral absence of the condyle and incomplete development of the articular fossa and eminence, causing facial asymmetries.

Answer 53

Aplasia

Question 54

This causes an open bite when in the TMJ.

Answer 54

Rheumatoid Arthritis

Question 55

This occurs when the condyles shorten, and the elevator muscles pivot the joint.

Answer 55

Open bite

Question 56

What color is the posterior band?

Answer 56

WHITE