Structural Incompatibility of the Articular Surfaces

Question 1

alterations in lubrication of the joint tissues can cause friction. what 3 things does friction increase?

Answer 1

tissue breakdown, abrasion, and sticking

Question 2

when friction of the joint tissues occurs, adherences can occur in both the ___ and ___ joint space. what does this usually cause?

Answer 2

• superior and inferior joint space

- usually causes single click as surfaces separate and return to normal function

Question 3

adhesions occur when ___ develops between articular surfaces, causing ___

Answer 3

• fibrous tissue

- more permanent limitations to normal condyle/disc/fossa function

Question 4

___ from bleeding within the joint promotes formation of adhesions

Answer 4

hemarthrosis

Question 5

describe alterations in morphologic characteristics. when does clicking usually occur?

Answer 5

• changes in morphology of the disc, condyle, or fossa
• osseous, discal
• clicking usually occurs at the same interincisal position in both opening and closing movements

Question 6

subluxation hypermobility and spontaneous dislocation occurs as a result of condylar translation beyond ___

Answer 6

the articular crest/eminence

Question 7

is subluxation hypermobility and spontaneous dislocation considered pathologic?

Answer 7

not usually, but it can lead to elongation of the distal lamina and further alterations in joint function

Question 8

when does spontaneous dislocation occur?

Answer 8

beyond maximum opening and disc/condyle entrapment anterior to the eminence

Question 9

what is the typical patient reaction to spontaneous dislocation?

Answer 9

they often panic and try to force the mandible closed, causing further damage to the retrodiscal tissues

Question 10

what are some factors that predispose to disc derangements?

Answer 10

• steepness of the articular eminence
• morphology of the condyle and fossa
• joint laxity
• may be linked to higher levels of estrogen induced joint laxity
• hormonal factors
• attachment of the superior lateral pterygoid muscle
• inflammatory joint disorders
• synovitis, capsulitis, retrodiscitis
• arthridities

Question 11

what is arthridities?

Answer 11

osteoarthritis or degenerative joint disease and crepitation

Question 12

describe the dysfunctional continuum

Answer 12

1. normal healthy joint
2. loss of normal condyle-disc function due to macro or microtrauma
3. abnormal translatory movement between disc and condyle
4. posterior border of the disc becomes thinned
5. further elongation of the discal and inferior retrodiscal ligaments
6. disc becomes functionally displaced (single click, reciprocal click)
7. disc becomes functionally dislocated (dislocation with reduction (catching) or without reduction (closed lock))
8. retrodiscitis
9. osteoarthritis