EFDA Interview Questions: What to Ask and What Good Answers Sound Like
Questions, red flags, a practical task and a scorecard for EFDA hires.
A credential tells you what a candidate was trained to do and is permitted to do in their state; the interview tells you whether they can do the work in your chairs and stay inside your state's supervision line.
Structure the hour around four things: what their credential covers, how good their restorative and sealant work is, how efficiently they run the chair with the doctor, and whether they hold the line between their functions and yours.
Verify the credential before the interview, not during it.
Before the interview
Verify the credential before you talk.
Ask for three specifics up front: the exact title, the issuing state, and the expiration date.
Titles are state-specific — Pennsylvania certifies expanded function dental assistants, Ohio registers expanded function dental auxiliaries, California licenses RDAEFs — and DANB notes further variants such as LDA and RDA.
Check what they claim through your state board's verification search, or DANB's Verify Credentials tool.
Kentucky's board recognizes no EFDA title and issues no expanded-duty authorization at all — the employing dentist must verify training themselves.
The employer's duty can be explicit.
Georgia requires the employer to keep a copy of the assistant's course certificates readily available in the office.
In Nevada, a practice owner's failure to verify an expanded function dental assistant's license before offering employment or an independent-contractor contract is unprofessional conduct.
Then know your own side: which restorative functions your state delegates to an EFDA, which chair the hire will run, and how the schedule absorbs restorative appointments.
Score every answer against the duties in your job description, not a generic assistant role — or start with how to hire an EFDA.
Clinical and technical questions
Walk me through the last composite restoration you placed, from the doctor finishing the prep to the patient leaving.
What to listen for: An ordered sequence — matrix and wedge, incremental placement, contour, finish, occlusal check — and the dentist evaluating the work before the patient leaves.
In Pennsylvania, direct supervision includes the dentist personally evaluating the EFDA's work before dismissal; good candidates treat that as routine.
How do you check your own work before the doctor sees it?
What to listen for: Specific self-checks — margins, contacts, articulating paper, polish — and a clear sense of which judgments are not theirs: a Pennsylvania EFDA, for example, may not make final occlusal approvals.
The doctor is pulled into an emergency, and your patient is numb and waiting. What do you do?
What to listen for: Keep the patient comfortable and wait for authorization rather than improvising.
In Pennsylvania, every EFDA service requires a dentist present in the office who has authorized the procedure; in Ohio, an EFDA generally may not practice as an EFDA when the supervising dentist is not physically present — sealants and listed preventive services excepted.
Which restorative materials have you placed most, and which are you still getting reps on?
What to listen for: Named materials with honest volumes: Ohio's expanded function dental auxiliary scope includes placing amalgam and nonmetallic restorative materials — but what matters is how often they have actually done it.
What makes a sealant fail early, and what do you do with a tooth you cannot keep isolated?
What to listen for: Moisture control as the first suspect, and a willingness to re-book rather than seal over contamination.
Also a credential question: in California, pit and fissure sealants may be placed only by an RDA, RDAEF, RDH or RDHAP.
When have you taken final impressions, and for what?
What to listen for: Crown and bridge versus study models, and how they handled tissue management.
In California, an RDAEF licensed on or after January 1, 2010 may take final impressions for permanent indirect restorations under direct supervision — a candidate who cannot say which they took has probably taken fewer.
Walk me through turning a room over between restorative patients.
What to listen for: Barriers, instrument flow, and sterilization between patients — CDC's 2003 dental guidelines recommend cleaning and heat-sterilizing critical instruments before each use.
How have you kept a doctor's restorative schedule on time?
What to listen for: Mechanics, not adjectives: setup done before the patient sits down, transfer that never breaks the doctor's focus, turnover started while the doctor writes notes.
Scope, credential and compliance questions
What is the exact title of your expanded-function credential, who issued it, and when does it expire?
What to listen for: Precision, from memory.
Titles are state-specific — Pennsylvania's expanded function dental assistant, Ohio's expanded function dental auxiliary, California's RDAEF.
Training counts too: one of Pennsylvania's certification routes is a board-approved EFDA program of at least 200 hours of clinical and didactic instruction.
Which functions does your credential cover, and which stay with the dentist — here, in this state?
What to listen for: They draw the line where your state draws it.
Each state defines expanded functions differently — a Pennsylvania EFDA places and finishes amalgam and composite restorations and sealants, not the default everywhere.
Check any boundary they quote against your state's list.
Have you worked under a permit system? What did it actually cover?
What to listen for: Ask what their permit authorized.
Arkansas requires a permit for any expanded duties; its list — nitrous oxide/oxygen analgesia, radiographic equipment, coronal polishing, monitoring patients under deep sedation or general anesthesia — shows how different a permit state's delegation can be.
If your state splits restorative functions into categories or levels, which do you hold?
What to listen for: Missouri issues permits in five categories — restorative I, restorative II, removable prosthodontics, fixed prosthodontics and orthodontics.
Nebraska issues restorative permits at Levels I and II.
In Tennessee, each function carries its own board certification. 'The restorative one' is not an answer.
When did you last renew, and what continuing education have you done this cycle?
What to listen for: Pennsylvania EFDAs complete 10 hours per biennial period; Wisconsin's EFDA credential requires 12 per renewal; New Hampshire renews EFDA permits in odd-numbered years before May 1.
Lapses can be terminal — in Missouri, a permit not renewed within one year of its expiration date is void.
Which DANB credentials do you hold, if any — CDA, CPFDA, CRFDA?
What to listen for: More than 35,000 assistants hold DANB's CDA; the CPFDA covers coronal polishing, sealants and topical fluoride, and the CRFDA covers restorative functions, impressions, sealants and temporaries.
In New Mexico, a DANB CDA does not qualify an assistant for expanded functions without board certification — confirm claims through DANB's Verify Credentials tool and your board.
Have you worked on a team with more than one EFDA?
What to listen for: How they shared doctor time and where the bottlenecks were — your staffing may be capped: Ohio limits each dentist to two EFDAs practicing as EFDAs at a time, and New Hampshire allows a maximum of two EFDAs per practice regardless of dentist count.
Have you ever moved states with your credential? What did you have to do?
What to listen for: Arizona accepts an equivalent credential from another state plus clinical experience; Connecticut defines its EFDA by a DANB Certified Dental Assistant or Certified Orthodontic Assistant exam plus an EFDA program accredited by CODA, kept current.
You want someone who looked up your state's requirement before applying.
Team and patient questions
Tell me about a time you disagreed with a doctor about a restoration.
What to listen for: How they raised it — privately, with the radiograph in hand — and what they did when the final call went the other way.
Not who was right; whether they can disagree without a battleground.
A patient asks whether they really need the crown the doctor planned. What do you say?
What to listen for: Support for the dentist's plan without re-diagnosing it — a Pennsylvania EFDA, for instance, may not examine, diagnose or treatment-plan.
The good answer explains, reassures, and hands the decision back to the dentist.
How do you handle a patient who is unhappy with work you placed?
What to listen for: No defensiveness: they bring the doctor in, document the conversation, and follow the practice's protocol rather than negotiating a remake themselves.
When your chair runs long, how do you work with the sterilization tech and the front desk?
What to listen for: They warn people early, protect the schedule, and treat turnover as their job even when someone else executes part of it.
Why did you add expanded functions to your career?
What to listen for: A specific reason — continuity with nervous patients, taking procedures off the doctor's column, finishing a restoration start to finish. 'It pays more' is at least honest; ask what they did with the skill.
Red flags worth a follow-up
None of these is automatically disqualifying — each deserves a follow-up question first.
- Cannot name the exact credential, issuing state, or expiration date offhand.
- Describes placing restorations with no mention of the dentist's authorization or the pre-dismissal check.
- Treats a DANB certificate as automatic permission to perform expanded functions anywhere.
- Cannot walk through one restoration in detail — sequence, materials, their own quality check.
- Describes cutting, injecting or diagnosing as a routine part of the job.
- Is vague about whether the credential is currently active.
- Asks nothing about how you supervise, how you check their work, or how the schedule is built.
After the interview
After the sit-down, watch the hands.
Our research found no source that standardizes a practical test for EFDAs, so design the task around your operatory: a typodont exercise that mirrors your restorative mix — finish a composite on a prepped model, take an alginate impression, apply a sealant — scored against the same checklist every time.
Our skills assessments guide covers formats and scoring mechanics.
If the task becomes a working interview — productive work in your office — pay for the hours.
In 2018 the U.S. Department of Labor found a Nashville dental practice violated federal minimum wage requirements by requiring job candidates to do an unpaid "working interview"; a short session, an "observation" label, or the candidate's agreement does not change that.
Check your state dental practice act before any candidate performs intraoral work — each state's act sets who may do what — and ask your employment counsel if unsure.
The mechanics are in running a working interview.
Score every candidate on the same five dimensions before the team compares notes:
- Credential fit (gate) — right credential for your state, right category, current, documented before any offer.
- Restorative quality — narrates the sequence, self-checks honestly, welcomes the dentist's evaluation.
- Chair efficiency — keeps the doctor's column moving.
- Scope judgment (gate) — draws the credential line concretely and holds it under pressure.
- Team and patient — handles disagreement, complaints and hand-offs without drama.
Rate each dimension 1 to 3, and treat the gates as gates: a candidate who cannot document the credential, or cannot say where their functions end, does not move forward.
Break ties with the practical task and with reference checks that reach a dentist who has seen their work.
Re-verify before the offer — credentials lapse: in Missouri, a permit not renewed within one year of its expiration date is void.
If your shortlist includes general assistants who would need the credential first, that interview is a different conversation: dental assistant interview questions.
Hiring an EFDA?
Post the role with the expanded functions you actually delegate and the credential your state requires.