Lecture 6/7/8

Question 1

Additive wax technique

Answer 1

Step 1: Locate and place cusp cones
Step 2: Place cusp ridges and marginal ridges
Steps 3,4: Develop buccal and lingual cusp ridges and surfaces
Step 5: Place triangular ridges
Steps 6,7: Refine occlusion, finish and polish

Question 2

Kinematic Hinge Axis

Answer 2

True axis = kinematic hinge axis. Not easy to find without

pantograph.

Question 3

Arbitrary axis

Answer 3

This is arbitrary axis = close enough to kinematic without all of the time and money.

13 mm anterior to tragus on tragus-canthus line

Question 4

Be within

Answer 4

6 mm radius from true axis. If you do this,

error is almost negligible.

Question 5

Accuracy jumped up over time as this was modified

Answer 5

the bump at the condyle portion helped tremendously) - earbows with modifications.

Question 6

Working condyle

moves anywhere in

Answer 6

bennett’s angle.

Question 7

Non-working condyle moves in

Answer 7

3 directions - this is the reason for

the medial articulator wall.

Question 8

Angle between protrussive and W =

Answer 8

Bennett’s angle. On horizontal plane.

N = nonworking direction.

Question 9

The Frankfort Horizontal Plane

Answer 9

Forion, orbital (lowest part of orbital rim). FH plane.

Question 10

Occlusal plane is not parallel to

Answer 10

FH plane.

Question 11

Articulator mounting

Answer 11

First melt wax on. In the front,

those prongs help with this.

Question 12

Hanau’s Formula for the “lateral” angle (Bennett’s Angle)

Answer 12

L = H/8 + 12

Where, L= Lateral angle and H= Horizontal angle

Question 13

Significance of Ear Bow Transfer

Answer 13

• Relates maxillary cast to the Terminal Hinge Axis (manibular condyles)
• Orients the maxillary cast correctly in space using a third point of reference (occlusal plane)

-Is aligned parallel to the interpupillary line
(reference)

• Permits mounting of the maxillary cast on a semi-adjustable articulator
• The mandibular cast is mounted using a centric relation (CR) record

Question 14

Centric Relation (CR)

Answer 14

The maxillomandibular relationship in which the condyles articulate with the thinnest avascular portion of their respective disks with the complex in the anterior-superior position against the shapes of the articular eminencies. This position is independent of tooth contact.

Question 15

CR Each point on curve is an

equal amount of

Answer 15

opening.
Any point is CR (any level
of opening, you are in CR), including last point/phalange (still on arc of rotation).

Question 16

90% have .

Answer 16

COMI slide

Question 17

Initial point of contact =

Answer 17

CO centric occlusion.
CR is still CO, but CO is a descriptor for a specific CR. MI is not CR.
COMI slide or CRMI slide describe this.

Question 18

Methods of Recording CR

Answer 18

Bilateral manipulation
Chin point guidance
Anterior deprogrammer

Question 19

Bilateral manipulation

Answer 19

Using two hands to move the jaw.

Question 20

Anterior deprogrammer

Answer 20

A bit of acrylic When patient bites down, they bite on acrylic, and eventually deprogram themselves. This removes any abnormal biting so that a patient can move as they naturally do.

**Upward push, not backward.

Question 21

Centric Relation (CR) Record

Answer 21

Along the arc of rotation of the mandible No teeth touching
Thin
Soft
Fast setting Dimensionally stable Easily verifiable

Question 22

Casts mounting in CR 3Rs

Answer 22

Repeatable, reliable, reproduceable - 3Rs for this.

You will never see this with hand examination.

Question 23

Influence of articular guidance

Answer 23

The more you go to the front, you have more incisal guidance.

Question 24

Bow - mark 3rd point of reference

Answer 24

Marks 43 mm from occlusal plane. Same distance as orbit distance.