Occlusion for Conventional Dentures

Question 1

What equipment is needed for jaw registration?

Answer 1

Something to melt the wax and a wax knife
Dividers or a Willis bite gauge
Jaw registration paste
Shade and mould guide

Question 2

What are the steps of jaw registration?

Answer 2

1 - adjust upper record block for retention
2 - adjust upper record block for tooth position
3 - adjust upper record block for occlusal planes
4 - lower tooth position and horizontal jaw relationship
5 - measure vertical dimension and establish face height
6 - record registration
7 - select shade, mould and setting

Question 3

How can you adjust the upper record block for retention?

Answer 3

Use the wax knife and hot plate to make adjustments
May need to adjust the rim Labial/buccal

Question 4

What are areas of concern when adjusting an upper record block for tooth position?

Answer 4

Lip support
Incisal level
Midline
Buccal corridor
Occlusal plane

Question 5

What is often used to adjust the occlusal plane of an upper record block?

Answer 5

Foxes bite plane

Question 6

What is the neutral zone?

Answer 6

The potential space between the lips and cheeks on one side and the tongue on the other
That area or position where the forces between the tongue and the cheeks or lips are equal

Question 7

What is a class I skeletal relationship?

Answer 7

Shallow overjet and overbite

Question 8

What is a class II division 1 skeletal relationship?

Answer 8

Increased overjet and shallow overbite
Anteriors will meet

Question 9

What is a class II division 2 skeletal relationship?

Answer 9

Increased overjet and deeper overbite

Question 10

What is a class III skeletal relationship?

Answer 10

Edge to edge incisors and posterior crossbite
Try avoid reverse overjet anteriorly (retrocline incisors)

Question 11

What is the retruded contact position (RCP)?

Answer 11

Guided occlusal relationship occurring at the most retruded position of the condyles in the joint cavities
Limited by the lateral ligaments of the TMJ
Remains the same throughout life assuming nothing happens to the condyles
A reference point for mounting casts on an articular

Question 12

What is muscular position?

Answer 12

The position of closure produced by balanced muscle activity raising the mandible from rest to initial contact

Question 13

What is occlusal vertical dimension (OVD)?

Answer 13

The distance between a set point on the maxilla and a set point on the mandible when the teeth are in maximum intercuspation

Question 14

What is resting vertical dimension (RVD)?

Answer 14

When the mandible is at rest with the patient upright

Question 15

What can affect the RVD measurement?

Answer 15

Stress
Pain
Anxiety
These can tense up facial muscles

Question 16

What is the usual freeway space?

Answer 16

Usually 2-4mm

Question 17

What are the effects of excessive freeway space?

Answer 17

Reduced masticatory efficiency
Overclosed facial appearance and cheek biting
TMJ symptoms
Could get angular cheilitis

Question 18

What are the effects of reduced (inadequate) freeway space?

Answer 18

Excessive load on denture bearing areas
Continuous muscular activity results in pain
Aesthetic complaints - teeth too big, show too much teeth
Noisy dentures

Question 19

What are the final checks before recording registration?

Answer 19

Are blocks trimmed so teeth will be in the neutral zone
Do you have even contact with the upper block
Is OVD correct for patient, with adequate freeway space
Is central line correct
Are occlusal planes appropriate

Question 20

How is jaw registration recorded?

Answer 20

Cut notches on upper and lower blocks and apply jaw registration paste to upper and lower block
Ensure casts will seat back on models
Check for heel interferences
Prescribe an articulator

Question 21

Which articulator is used in GDH?

Answer 21

Fixed value lateral and protrusive

Question 22

Which other articulators can be used?

Answer 22

Simple hinge
Semi-adjustable

Question 23

What are the final steps in jaw registration?

Answer 23

Select shade, mould and setting
Write lab prescription

Question 24

What should be written under stage in the lab card after jaw registration?

Answer 24

Try in
Please mount on articulator to registration shown, set-up for try in with teeth shade x and moulds as below