Whether a dental assistant can take impressions depends on your state — it's one of the expanded functions a trained dental assistant may be allowed to perform.
Impressions for study models and appliances like retainers or nightguards can be within an assistant's scope where they've had training, while final impressions for crowns and bridges, and fabricating temporaries, tend to be more restricted and often require expanded-function credentialing.
As always, the exact rule depends on your state.
The short answer
Taking impressions is a routine expanded duty — DANB lists it among the common examples of the expanded functions that states define differently — and whether trained assistants may do it is decided state by state.
Where the rules tighten is around which impressions: those for study models, custom trays, and appliances are broadly allowed, while final impressions used to fabricate crowns, bridges, and other prosthetics are more often restricted or reserved for expanded-function assistants.
So the answer is usually "yes" for the everyday impressions and "it depends on your state and credential" for the definitive restorative ones.
Impression scope varies by state and impression type
What taking impressions involves
An impression captures the shape of the teeth and surrounding tissue so the dentist or lab can build something that fits.
Traditionally that means loading a tray with a material like alginate or polyvinyl siloxane and seating it in the patient's mouth; increasingly it also means capturing the same detail with an intraoral digital scanner.
Those impressions become study models, custom whitening or nightguard trays, retainers and other appliances, aligner records, and the working models a dental lab technician uses to build the finished piece.
It's precise, hands-on work — and one of the skills that makes a trained assistant valuable chairside.
Everyday impressions vs. final restorative impressions
The distinction that drives the rules is what the impression is for.
Impressions for study models, custom trays, and appliances are generally within a trained assistant's scope.
The final impression that a crown, bridge, or denture is actually made from is a different matter — because the fit of a permanent restoration depends on it, more states restrict who may take it, sometimes limiting it to expanded-function assistants or to the dentist.
Digital scanning sits in the same logic: where a state treats scanning like the impression it replaces, scanning for models or aligners is generally fine, while scanning for a final restoration follows the stricter rule.
Check how your state classifies each.
The training you usually need
DANB lists taking impressions among the common examples of expanded functions that states define differently, and for basic impressions the requirement is often just training — sometimes as part of a dental assisting program or on-the-job instruction.
The more advanced work — final restorative impressions and temporaries — typically calls for an expanded-function credential or a specific permit earned through a board-approved course.
It's the same expanded-function tier that governs duties like coronal polishing and placing sealants.
For how these state permits relate to national certification, see our guide to CDA vs. RDA and the dental assistant title maze.
How to confirm your state's rule
Your state dental board lists which impression and temporization duties assistants may perform and the training or permit each requires; the ADAA's state pages are a useful starting map.
Where they differ, the board is the authority.
Because impression scope splits by type and by state, confirm your state's exact rule — especially for final impressions and temporaries — before offering them, and note the date you checked, since these rules are revised periodically.
This article is general career information, not legal or clinical advice. Expanded-function and scope-of-practice rules vary by state and change over time — confirm current requirements with your state dental board.