Articulators

Question 1

What is an articulator?

Answer 1

mechanical device representing the jaw members and the TMJ to which the maxillary and mandibular casts are attached to simulate different mandibular movements

Question 2

What are the mandibular movements?

Answer 2

• opening and closing
• protrusive
• right and left

Question 3

What is the sagittal (horizontal) condylar path?

Answer 3

path travelled by the condyles during protrusive movement (downward + forward)

Question 4

What is the lateral condylar path?

Answer 4

path travelled by the condyles during lateral movement (downward + forward + medial)

Question 5

What are the articulator movements?

Answer 5

• opening and closing
• protrusive
• right and left

Question 6

What are the functions of the articulator?

Answer 6

• act as a patient in the absence of the patient
• simulate, but not duplicate, all possible mandibular movements
• diagnosis and treatment planning (to observe all possible movements)
• arrangement of artificial teeth for complete dentures and removable partial dentures
• fabrication of occlusal surface for dental restorations

Question 7

What are the advantages of articulators?

Answer 7

• visualisation of occlusion (lingual aspect)
• no need for patient cooperation
• decrease chair time and patient appointment
• patient’s saliva, tongue and cheek are not factors when using an articulator

Question 8

According to records accepted, articulators are classified into…

Answer 8

• simple hinge articulators
• mean value (fixed condylar path) articulators
• adjustable articulators (semi and fully adjustable)

Question 9

Is Bonwill triangle accurate?

Answer 9

No

Question 10

Is maxillary facebow accurate?

Answer 10

Yes

Question 11

What does Arcon stand for?

Answer 11

Articulator condyle on normal

Question 12

What are the movements and records taken from the patient for a simple hinge articulator?

Answer 12

movements
- opening and closing
records taken from patient
- centric occluding relation

Question 13

What is centric occluding relation?

Answer 13

centric relation + proper vertical occlusal dimension

Question 14

What is the movement of articulator on protrusive movement?

Answer 14

Upward and backward

Question 15

Does the mandible move in the articulator?

Answer 15

No

Question 16

What are the movements of mean value articulators?

Answer 16

• opening and closing
• protrusive (fixed 30-40 degrees)
• lateral (fixed 12-20 degrees)

Question 17

What are the records taken for mean value articulators?

Answer 17

to mount the upper cast
- Bonwill triangle (ASA)
- facebow record )AlMahdy articulators only)
to mount the lower cast
- centric relation

Question 18

Is the incisal angle and table fixed in mean value articulators?

Answer 18

Yes, 30 degrees incisal angle

Question 19

Are all mean value articulators Arcon?

Answer 19

No

Question 20

Is the intercondylar distance fixed in mean value articulators?

Answer 20

Yes

Question 21

What are the two types of semi-adjustable articulators?

Answer 21

• Hanau
• Whip mix

Question 22

What are the movements of semi-adjustable articulators?

Answer 22

• opening and closing
• protrusive (taken from patient)
• lateral (Hanau’s equation with Hanau’s articulator or taken from patient with Whip mix articulator)

Question 23

What are the records taken using semi-adjustable articulators?

Answer 23

to mount the upper cast
- Bonwill triangle (unlikely)
- maxillary facebow for all designs
to mount lower cast
- centric relation

Question 24

How to record protrusive movement of semi-adjustable articulators?

Answer 24

taken from patient and adjusting horizontal condylar guidance

Question 25

How to record lateral movement of semi-adjustable articulators?

Answer 25

adjusting lateral condylar guidance using either Hanau's equation or taken from the patient using Whip mix articulator

Question 26

What is Hanau's equation?

Answer 26

L = H/8 + 12

Question 27

How to record lateral movement through Whip mix articulator?

Answer 27

taken from patient - right record to adjust left lateral condylar guidance - left record to adjust right condylar guidance

Question 28

Is Hanau articulator Arcon?

Answer 28

no

Question 29

Is Whip mix articulator Arcon?

Answer 29

yes

Question 30

Is the incisal table and angle fixed in semi-adjustable articulators?

Answer 30

no

Question 31

Is the intercondylar distance fixed in semi-adjustable articulators?

Answer 31

yes

Question 32

What are the movements of fully-adjustable articulator?

Answer 32

- opening and closing - protrusive (obtained from patient) - lateral (taken from patient)

Question 33

What is the name of a fully-adjustable articulator?

Answer 33

Denar

Question 34

What are the records taken for a fully-adjustable articulator?

Answer 34

to mount upper cast - facebow to mount the lower cast - centric relation

Question 35

How is protrusive records taken for fully-adjustable articulator?

Answer 35

from patient to adjust horizontal condylar guidance

Question 36

How is lateral records taken for fully-adjustable articulator?

Answer 36

taken from patient - right record to adjust left lateral condylar guidance - left record to adjust right condylar guidance it records path of condyle from the beginning of movement to the end of the movement

Question 37

Is the incisal angle and table fixed in fully-adjustable articulators?

Answer 37

no

Question 38

Are fully-adjustable articulators all Arcon?

Answer 38

yes

Question 39

Is the intercondylar distance of fully-adjustable articulators fixed?

Answer 39

no

Question 40

What are the minimal requirements of articulators?

Answer 40

- maintain correct horizontal and vertical relationships of patient's cast - casts must be easily removed and attached to the articulator - have an incisal guide pin with a positive stop to preserve patient's vertical dimensions - open and close in a hinge-like fashion - accurate, rigid and of non-corrosive materials - moving parts resist water - adjustment should be able to move freely and be definitely secured

Question 41

What are some additional requirements for articulators?

Answer 41

if the denture is fabricated with balanced occlusion (3 points of contact in centric and eccentric), the articulator should... - accept facebow - allow protrusive and lateral movements - have adjustable incisal guidance

Question 42

Do all semi-adjustable articulators accept facebow records?

Answer 42

yes

Question 43

Can fully-adjustable articulators be linked to a computer using a software?

Answer 43

yes