CAD/CAM Digital Dentistry Flashcards

Which file format is the industry standard for sharing digital impression data between scanners and milling software?

Answer: STL (Standard Tessellation Language)

STL is the most widely accepted open format for sharing 3D scan data across CAD/CAM systems.

When milling zirconia, which milling stage requires the material to be in its pre-sintered (soft) state?

Answer: Green-state milling before sintering

Pre-sintered (green-state) zirconia is milled before the final sintering cycle that shrinks and densifies the material.

What does the term 'emergence profile' refer to in CAD design of a crown?

Answer: The contour of the restoration as it exits the gingival margin

Emergence profile describes how the restoration transitions from the subgingival finish line through the gingival tissue.

Which milling parameter most directly affects the surface roughness of a milled ceramic restoration?

Answer: Stepover distance between toolpaths

A smaller stepover distance between adjacent toolpaths produces a smoother surface by reducing the scallop height.

In a chairside CAD/CAM workflow, which component captures the optical impression directly in the patient's mouth?

Answer: Intraoral scanner

An intraoral scanner uses structured light or laser to capture a digital impression without impression material.

What is the primary reason zirconia restorations must be sintered at high temperatures after milling?

Answer: To convert the crystalline phase and achieve final strength and density

Sintering transforms porous pre-sintered zirconia into dense, high-strength tetragonal-phase ceramic.

Which occlusal design concept in CAD software distributes occlusal forces through the long axis of posterior teeth?

Answer: Centric stops with axially directed contacts

Axially directed centric stops minimize lateral forces and protect both the restoration and the periodontal structures.