3rd Session: Articulators (1-29, Lamounier)

Question 1

What is an articulator?

Answer 1

A mechanic device designed to simulate the movements of the mandibular arch in relation to the maxillary arch.

Question 2

How are articulators used diagnostically?

Answer 2

Mounting diagnostic casts improve the visualization of both static and functional interrelationships of the teeth. Helps establish an accurate diagnosis.

Question 3

How are articulators used for treatment plans?

Answer 3

Visualize the end result! Plan the steps of the treatment.

Question 4

What are the benefits of using articulators when making the treatment plan?

Answer 4

Selective grinding - no damage to the real teeth

Functional prewax - help visualize what the best design is

Aesthetic (diagnostic prewax) - help visualize function and esthetics together

Design fixed restorative prostheses - mounting casts help determine the best way.

Orthodontic setup - visualize sequence

Patient education!

Question 5

What are the classifications of the articulators?

Answer 5

Location of condyle: arcon vs non-arcon

Usage: non-adjustable, semi-adjustable, and fully adjustable

Question 6

What is an arcon articulator?

Answer 6

Condylar head on the lower member of the articulator.

Question 7

What is a non arcon articulator?

Answer 7

Condylar head on the upper member of the articulator (what we have!)

Question 8

What are the types of articulators?

Answer 8

Nonadjustable articulator
Semi-adjustable articulator
Fully adjustable articulator

Question 9

Describe the basics of a non-adjustable articulator:

Answer 9

Most simple design
No adjustments
Can only imitate intercuspal position (ICP) accurately
Can not accurately replicate protrusive and laterotrusive movements

Question 10

What are the advantages of non-adjustable articulators?

Answer 10

Inexpensive

Easy to mount casts, faster

Question 11

What are the disadvantages of non-adjustable articulators?

Answer 11

Only one contact - no eccentric movements
More time adjusting the restorations intraorally
Far outweigh the advantages!

Question 12

Describe a semi-adjustable articulator:

Answer 12

More variability in duplicating condylar movements
Duplicate occlusal contact and eccentric movements
Information about patient’s specific movements

Question 13

What is the condylar inclination?

Answer 13

The angle at which the condyle descend along the articular eminence.
Average = 25 - 30 degrees

Question 14

What is the Bennett angle?

Answer 14

The angle where the orbiting condyle moves inward in a laterotrusive movement.
Average = 15 degrees

Question 15

What is the intercondylar distance?

Answer 15

Distance between the rotation centers of the condyles can have effect on the mediotrusive and laterotrusive pathways.
Average = 110 mm

Question 16

How is the patient’s information transferred to the semi-adjustable articulator?

Answer 16

1. Facebow transfer: Use to mount the maxillary cast. 3 points of reference
2. Centric relation record: use to mount the mandibular cast.
3. Eccentric interocclusal records: use to adjust the articulator so that it follows the condylar movement of the patient.

Question 17

What are the advantages of semi-adjustable articulators?

Answer 17

Can be adapted to specific condylar movements

Reduced intraoral adjustments for restorations

Question 18

Disadvantages of semi-adjustable articulators?

Answer 18

More time

Expensive

Question 19

What are the names of the adjustments possible to make on fully-adjustable articulators?

Answer 19

1. Condylar Inclination
2. Bennet Angle (Lateral Translation)
3. Rotating Condylar Movement
4. Intercondylar Distance

Question 20

What is the purpose of the facebow?

Answer 20

Records the relationship of the maxillary arch to the horizontal axis of rotation of the mandible in order to transfer that info to the articulator.

Question 21

What types of facebow are there?

Answer 21

Hinge axis transfer bow (kinematic): uses a hing axis locator to find the exact hinge.

Simple facebow (earpiece): uses the ears to approximate the hinge axis.

Question 22

What is the set distance between the incisal edge of the lateral incisor to the lateral part of the nose?

Answer 22

43 mm