What is the PRIMARY purpose of border molding (muscle trimming) for a complete denture?

To increase the vertical dimension of occlusion
To record muscle function at the vestibules and establish proper denture extension
To record fine surface detail of the residual ridge
To stabilize the tray during final impression

Show answer and explanation

Correct answer: B. To record muscle function at the vestibules and establish proper denture extension

Border molding establishes the proper periphery/extension of the denture base by recording functional muscle movements at the vestibule boundaries.

A. Vertical dimension is established during jaw relation records — not border molding.
B. CORRECT. Border molding captures the functional limits of the denture-bearing area — muscle attachments and soft tissue reflections at vestibule boundaries. This determines optimal flange extension for maximum retention with functional comfort.
C. Fine surface detail of ridge mucosa is recorded in the final (wash) impression — not during border molding.
D. Stabilization of the tray is a benefit of the softened material but not the primary clinical purpose of border molding.

More Prosthodontics & Occlusion practice questions