4; Face Bow

Question 1

This is a caliper-like instrument used to record the spatial relationship of the maxillary arch to some anatomic reference point(s) and then transfer this relationship to an articulator.

Answer 1

face bow

Question 2

What are the three anatomic references of a face bow

Answer 2

mandibular condyles
THA
3rd point of reference

Question 3

A face bow transfers what

Answer 3

the rotational axis of the patient’s condyles (two axis) and an imprint of the maxillary occlusal arch

Question 4

What is the fixed triad of the facebow

Answer 4

R/L condyles

imprint of maxillary occlusal plane

Question 5

This individual was DDS who invented the face bow, articulators, vulcanizer, and the automatic dental mallet

Answer 5

Dr. George Snow

Question 6

This is an important starting point in complete dentures

Answer 6

locating the maxillary occlusal plane

Question 7

What three steps should be taken before applying the face-bow transfer

Answer 7

facial contour the maxillary occlusal rim
mark the middle
align the fox plane

Question 8

What is special about the arc on articulator

Answer 8

“articulator” “condyle”

condylar path elements in upper member, condylar elements in lower member

Question 9

The registration of the bitefork of the face-bow records the maxillary occlusal plane. What is recorded on the bottom of the bitefork?

a. Centric relation
b. Centric occlusion
c. Vertical dimension
d. Thumb print for ID
e. No record

Answer 9

E. No record

Does not record any mandibular registration

Question 10

Which type of bite fork should you use

Answer 10

dentures bite fork with holes

Question 11

What should you add to the maxillary occlusal plane wax, when using a bitefork

Answer 11

reference divots; good cuts, deep grooves

Question 12

What bite registration paste is used onto fork and into the holes

Answer 12

Take 1 Advanced

Question 13

True or False

It is the easiest to have the patient bite on the bitefork to hold it in place

Answer 13

False; don’t have the patient bite the bitefork in place

Question 14

Where should the third point of reference be

Answer 14

point 43mm superior to edge of occlusal wax rim

Question 15

Where should you record the patients midline

Answer 15

in the anterior of the maxillary wax rim

Question 16

Why mount the face-bow in the ear

Answer 16

arbitrary hinge axis is the closest point to the true hinge axis

Question 17

What are the steps (9) to properly taking a face bow transfer

Answer 17

1. Align bitefork against maxilla with notch at anatomical midline.
2. Secure shaft assembly to underside of measuring bow.
3. Slide the shaft of the bitefork through the #2 clamp.
4. Position the bow in the external auditory meatus.
5. Position the anterior pointer to the third point of reference.
   Option: sight 3rd point of reference through notch on top of bow.
6. Do not use the patient’s bite forces to stabilize the bite fork!
7. Tighten #1 clamp, which faces the operator.
8. Tighten #2 clamp, which faces the operator.
9. Intercondylar distance can be documented for patient’s record.

Question 18

What are the four steps to properly transferring the face bow

Answer 18

1. With all adjustments made and screws tightened to hold the parts of the face bow in place, remove entire assembly patient’s mouth.
2. Remove bitefork and transfer jig shaft assembly from the bow.
3. The bow is not mounted on the articulator.
4. Bitefork shaft assembly sent to laboratory for mounting upper casts.
   Measuring bow can be used on next patient.

Question 19

How would you properly index the cast and why

Answer 19

Easy removal, easy replacement, required for eccentric records.
Cut an “X” in the base of both casts about 1/4” deep.
Vaseline this “X” and around the border.
Soak the casts in water

Question 20

This was invented to utilize an adjustable mechanical instrument with attached casts that will simulate mandibular movements

Answer 20

Hanau semi-adjustable arcon articulator

Question 21

What two anatomical designs does the Hanau articulator follow

Answer 21

Condylar fossa/path in the upper member.

Condylar head/element in the lower member.

Question 22

What are three uses of the Hanau articulator

Answer 22

To accept and mount the face-bow transfer record for the maxillary arch.
To accept/mount the centric relation record for the mandibular arch.
To utilize the maxillary/mandibular orientation of casts for clinical and laboratory procedures.

Question 23

Bennett calibration is setting what

Answer 23

the immediate side shift

Question 24

Condylar guidance is setting what

Answer 24

the protrusive movement

Question 25

What is the incisal guide pin set it

Answer 25

at zero

6th large black line

Question 26

Loosening the centric lock changes what

Answer 26

the articulator from hinge to semi-adjustable

Question 27

What is the lateral condylar guidance set to

Answer 27

15° = Bennett angle

Question 28

The incisal pin must be touching what

Answer 28

the incisal guide table on the mark

Question 29

True or False

Once set, it is okay to go back and adjust the uncial pin

Answer 29

NO, never adjust the incisal pin