What is the tripoding technique used for on a diagnostic cast?

To adjust proximal contacts before framework fabrication
To measure the retentive force of a clasp assembly
To record three reference marks that allow the cast to be repositioned on the surveyor at the identical tilt
To measure the vertical dimension of occlusion

Show answer and explanation

Correct answer: C. To record three reference marks that allow the cast to be repositioned on the surveyor at the identical tilt

A. Proximal contacts are adjusted intra-orally or on articulated casts — not a surveying function.
B. Retention is assessed by measuring undercut DEPTH with an undercut gauge — a separate surveyor function from tripoding.
C. Correct. TRIPODING means scribing three widely separated dots on the cast with the analysing rod locked at a fixed vertical height, once the ideal tilt has been chosen. Those three marks let anyone re-orient the cast on the surveyor to exactly the same tilt later, preserving the recorded survey lines and the PATH OF INSERTION.
D. Vertical dimension is recorded clinically with occlusion rims and facial measurements, not by surveying.

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