Teeth, TMJs & Articulators

Question 1

Guardsman fracture

Answer 1

Force from chin causing a bilateral condyle fracture

Question 2

What will determine a protruding movement of the jaw?

Answer 2

1. Incisor guidance
2. Cusp inclines
3. TMJ

Question 3

Right movement of the jaw: What happens with the jaws?

Answer 3

1. Right condyle rotates round vertical axis moves outwards but stays in the area of the glenoid fossa.
2. Left condyle moves forwards

Question 4

What other teeth may determine the movement of the jaws?

Answer 4

Canine

on the right handside the patient is canine guided.
on the left handside the patient is group function guided.

Question 5

Mandibular movement guided by

Answer 5

teeth and TMJ

Question 6

Simple casts for…

Answer 6

static analysis of teeth
- Orthodontic analysis
- Wear analysis

Question 7

Answer 7

hand held casts

Question 8

Hand held casts

Answer 8

Analysing the teeth in the intercuspal position (only useful if enough reference teeth) - typically used by orthodontists for analysing overbite/underbite etc.

Question 9

Answer 9

Simple hinge articulator

Question 10

Simple hinge articulator

Answer 10

Not a simulator of movement (not really an articulator)
Cast relocator
Movements not representative (hinge is not in the same place as the hinge in the jaws

Question 11

Answer 11

Plane line articulator

Question 12

Plane line articulator

Answer 12

Hinge axis may be more anatomical but arbitrary (as amount of plaster you may use isn’t accurate)

Limited value for simple restorations - in particular those not involved in guidance.

Question 13

Answer 13

Average value articulator

Question 14

Average value articulator

Answer 14

1. Articulator hinge axis nearer condylar hinge
   axis
2. Average condylar guidance angles
3. Average excursive movements possible (lateral, protrusive etc)
4. Use:
   – Simple fixed prostheses for
   teeth not involved in guidance
   – removable prostheses

Question 15

Answer 15

Denatus articulator (non-arcon articulator; condyle part of maxillary component)

Question 16

Answer 16

Denar Mark II Articulator (arcon articulator; condyle part of mandibular component)

Question 17

Denatus articulator (non-arcon articulator)

Answer 17

Not really used anymore, less anatomical

Question 18

Denar Mark II Articulator (arcon articulator)

Answer 18

Arcon - anatomical looking

Question 19

Difference between arcon and non arcon?

Answer 19

the Arcon articulator copies the natural bones of the skull, while the non-Arcon articulator is in reverse, with the condyle moving in the opposite direction (Figures 3 and 4).

Question 20

Answer 20

Ear bow

Question 21

Face bow

Answer 21

Covered with soft wax, push onto the maxillary arch.
Move the bow of the articulator until in the ears.

Question 22

How is the condylar guidance path recorded for the arcon articulator?

Answer 22

Record resting cusp position (RCP). Then retruded, protruded, then two lateral occlusions this allows guidance planes to be programmed into the articulator

Question 23

When would you use the arcon articulator?

Answer 23

If the tooth under reconstruction was involved in the retruded/protruded position.