Cast Surveying

Question 1

What are the instruments used when surveying a cast?

Answer 1

Analysing rod, graphite marker and undercut gauges

Question 2

What is the first stage of surveying a cast?

Answer 2

Lay cast flat with a protractor or flat object on top to ensure it is flat.

Mark tripoding lines to ensure this angular ion can be repeated.

Question 3

How should you use the graphite marker to survey? What should be done after?

Answer 3

Only survey abutments and all soft tissue undercuts, also survey palatial side of teeth.

to mark upper survey line run graphite marker around greatest bulbosity of the tooth with end of the marker aligned with gingiva.

to mark lower survey lines, have graphite marker in sulcus depth.

after, undercuts should be marked with a straight line and 0.25mm undercut gauge.

Question 4

How may you alter the path of insertion? Which way can the cast be tilted?

Answer 4

Cast can only be tilted towards you and slightly left or right as this means the denture will be inserted forward, not from behind the teeth.

cast should be angulated to remove anterior undercuts and tripod lines re-drawn in order to replicate angulation.

Question 5

What should be done if an altered path of insertion is indicated?

Answer 5

Cast should be resurveyed in red graphite to show the undercuts present with altered path of insertion.

undercuts can then be marked with a straight line and undercut gauge of 0.25mm

Question 6

Why do you use a surveyor?

Answer 6

To indicate the maximum convexity of the tooth/alveolar process in relation to a planned path of insertion

Question 7

What is the path of insertion?

Answer 7

The path followed by a denture from its first contact with the teeth/soft tissues until it is fully seated

Question 8

What is the common path of displacement?

Answer 8

Path in which denture would be displaced

Question 9

Where are the undercuts?

Answer 9

Anything below the first upper or second lower survey line.