Teeth fit in (Lab) + Trial (Clinic)

Question 1

What is the technique for setting teeth up on an occlusal rim (on the temporary base)?

Answer 1

• Heat the wax with a wax knife
• Slice into the wax to form several grooves where teeth are to be positioned
• Insert teeth into the softened area
• Start with the left central incisor first, right central, left lateral + canine, right lateral + canine

Question 2

How are upper centrals positioned?

Answer 2

• Slight distal tilt (from labial view)
• On occlusal plane
• Neck has slight posterior tilt (from proximal view)

Question 3

How are upper laterals positioned?

Answer 3

• More posterior tilt than centrals
• 0.5 - 1mm above occlusal plane
• Neck more posterior tilt than centrals

Question 4

How are upper canines positioned?

Answer 4

-central

Question 5

How are upper first premolars positioned?

Answer 5

• Vertical to occlusal plane/curve of spee

- Only buccal cusp set on occlusal plane (lingual cusp is slightly above due to being smaller)

Question 6

How are upper second premolars positioned?

Answer 6

• Vertical to occlusal plane

- Both cusps on occlusal plane

Question 7

How are upper 1st molars positioned?

Answer 7

• Tilted mesially and lingually at the neck (relative to perpendicular drawn to occlusal plane)
• ML cusp only one that touches occlusal plane

Question 8

How are upper 2nd molars positioned?

Answer 8

Tilted mesially and lingually at the neck

-All cusps sit on occlusal plane

Question 9

What two planes determine the set up of the upper posteriors?

Answer 9

• Canine and premolar buccal surface

- Buccal surface of molars

Question 10

What two factors should be taken into account when setting up lower posteriors?

Answer 10

• Ensure maximum contact between upper and lower teeth
• Ensure lower teeth are positioned over lower ridge for stability (i.e. that they are placed on the ridge crest of the occlusal rim)

Question 11

How is the lower 1st premolar positioned?

Answer 11

• Centered over lower ridge (highest point of lower rim)

- Buccal cusp sits comfortably in upper fossa

Question 12

How is the 2nd premolar positioned?

Answer 12

• Centered over the lower ridge
• Buccal cusp sit comfortably in upper fossa
• Upper lingual cusp should be in line with lower ridge

Question 13

How is the 1st molar positioned?

Answer 13

• Centered over the lower ridge
• Buccal cusps sit comfortably in upper fossa
• Upper lingual cusp should be in line with lower ridge

Question 14

How is the 2nd molar positioned?

Answer 14

• Centered over the lower ridge
• Buccal cusps sit comfortably in upper fossa
• Upper lingual cusp should be in line with lower ridge

Question 15

What is the order in which posterior teeth should be set?

Answer 15

Upper 4
Lower 5
Upper 5
Lower 6
Upper 6
Lower 7
Upper 7

Question 16

What does the process of festooning involve and how is it done?

Answer 16

Contouring of the wax to make it resemble the final denture

1. Extend thin layer of wax 1-2mm beyond gingival margin of acrylic teeth (basically extend it past CEJ). Add extra thickness of wax to gingiva for carving later
2. Use lechron carver at 45 degree angle to carve half circles in the wax, follow line of gingival margin with carver tip + scrape away excess wax
3. Scribe concave lines from interproximals of teeth to within 3-5mm of labial + buccal vestibules
4. Shape areas of wax between lines to resemble root eminences
5. Use pin flame to smooth over wax
6. Rub with wet cotton wool to add shine

Question 17

What should be checked at the trial insertion?

Answer 17

• Extension and shape of saddle and major connectors
• Compatability with neutral zone
• Stability
• Retention
• Aestheticws
• Occlusion (teeth in contact without dentures should remain in contact when biting, if guidance existed before denture should not interfere with it, no non-working side interferences)
• How pt feels
• Speech

*If satisfied ask technician to process and finish denture, if chrome can use opaque resin to mask grey appearance of Co/Cr alloy behind anterior teeth