Setting teeth

Question 1

What is an occlusal plane guide?

Answer 1

• clear Perspex sheet that is fitted to the lower base to correspond with the occlusal plane on the upper rim
• this can be drawn on to help align teeth.

Question 2

How should the mould of the teeth be chosen?

Answer 2

Correspond with the width of the canine lines

Question 3

How do you ensure that the incisal edge is parallel to the occlusal plan?

Answer 3

Long axis of the tooth is not parallel to the centre line

Question 4

How should the upper anteriors be set?

Answer 4

• proclined
• within the profile of the rim

Question 5

Define overlap.

Answer 5

Relationship between upper and lower anterior teeth in Class 1 and 2 jaw relationships, the anteriors hang over the lowers.

Question 6

Define overjet.

Answer 6

Horizontal distance between palatal aspect maxillary anterior teeth and the labial aspect of mandibular anterior teeth.

Question 7

What is the IGA?

Answer 7

• incisive guidance angle
• recommended 10-15 degrees
• the angle at which the anterior teeth should be set to facilitate occlusion

Question 8

Why should space be left when setting the lower anteriors?

Answer 8

• allows for centric relation
• facilities occlusal balance

Question 9

Describe the long axis of lower anterior teeth.

Answer 9

• should protrude when viewed sagittally
• lower canines should be more vertical

Question 10

What order should teeth be set in?

Answer 10

• upper anteriors
• lower anteriors
• upper posteriors
• lower posteriors

Question 11

How should posterior teeth be chosen?

Answer 11

The shallower the ridge, the lower the cusp height

Question 12

What is the Hanua Quint?

Answer 12

• sagittal condylar guidance angle (SCGA)
• inclination of occlusal plane
• compensating curves
• cusp angle
• incisal guidance angle (IGA)

(length of occlusal table)

Question 13

What is the SCGA?

Answer 13

35 degrees

Question 14

What is the inclination of the occlusal plane?

Answer 14

• maxilla to hinge axis relationship
• between horizontal and 10 degrees

Question 15

What are compensating curves?

Answer 15

Allow for downward travel of the condyle

Question 16

What is the cusp angle?

Answer 16

0-30 degrees

Question 17

Why is a shortened occlusal table used?

Answer 17

• teeth shouldn’t be set on an inclined plane
• causes instability

Question 18

How are maxillary posterior teeth set?

Answer 18

• supporting cusps are set directly over the centre of the midline in the lower
• the posterior teeth should form one long fissure for the lower posterior supporting cusps

Question 19

Where is the centric relation position?

Answer 19

Deepest part of the fissure in a lower posterior tooth

Question 20

What is a supporting cusp?

Answer 20

Maxillary anterior tooth, the cusp that engages in the lower fissure

Question 21

Why is marginal ridge position important?

Answer 21

To provide a common fossa for the opposing supporting cusp

Question 22

What should be considered when waxing a denture?

Answer 22

• root
• bone covering root
• tissue covering bone

Question 23

What gives a more natural appearance to the dentures?

Answer 23

Papilla that are of different heights and thicknesses

Question 24

How does denture shape affect stability?

Answer 24

• denture needs to be shaped to withstand forces from the buccinator and the tongue
• thicker around the ridge and thin and fan towards the sulcuses