Dental Assistant Certification: Which One You Need and How to Get It
In the U.S., dental assistant certification can refer to a national credential, a state credential, or a school's certificate of completion. Find your situation below to see which one you need.
Find your route
| If this is you | Relevant path or requirement | What to do now |
|---|---|---|
| You graduated from a CODA-accredited dental assisting or dental hygiene program, you are within 90 days of graduating from a CODA-accredited dental assisting program, or you hold an RDH license from any state except Alabama | DANB CDA, eligibility Pathway I | Apply for the full CDA exam (RHS + ICE + GC together): $450. If you're a dental assisting student within 90 days of graduation, your program director completes DANB's Intent to Graduate form. |
| You have 3,500+ hours of dental assisting work, earned over at least 2 and at most 4 years, plus a high school diploma or GED | DANB CDA, Pathway II | Have a licensed dentist sign DANB's Employer Work Experience Statement, verifying both your hours and the required training and competence (letters and pay stubs aren't accepted), then apply: $450. |
| You're new, in a program that isn't CODA-accredited, or under 3,500 hours | Check your state and target credential first. RHS and ICE themselves have no eligibility requirements | If those exams fit your goal, RHS/ICE together costs $375. Their passes can count toward NELDA or CDA within each credential's completion period, but you must separately meet its eligibility rules. NELDA excludes CODA graduates and applicants with more than 3,000 work hours; compare the NELDA and AMT routes below before paying. |
| You're a student or graduate of a CODA-accredited DDS/DMD program or a DANB-accepted dental-school post-baccalaureate program, you graduated from a dental school outside the U.S. or Canada, or you're a former CDA | DANB CDA, Pathway III | Apply with your degree, enrollment, license or old CDA number: $450. |
| Your school or the military trained you and works with AMT, or you have qualifying work or teaching experience | AMT Registered Dental Assistant, RDA(AMT) | $150, covering application, exam and first annual fee. Check which of AMT's five routes you fit (below). |
| You need to take x-rays or perform expanded functions | Your state's credential | Look up your state on DANB's state requirements page, then read your state board's rules. A national certification may or may not count there. |
Fees are DANB's 2026 standard fees (active-military rates are lower) and AMT's current RDA fee. Last verified October 23, 2026.
Every DANB CDA pathway also requires current, hands-on CPR, BLS or ACLS from a DANB-accepted provider, valid through your whole 60-day testing window. (2026 CDA application packet, pp. 3–4, 11–13; CDA exam page; NELDA packet, pp. 3–4; AMT RDA)
Three different things often get called certification:
- A school's certificate of completion records that you finished a training program. It isn't a certification, though it may make you eligible to sit for one.
- A national certification (DANB CDA or NELDA, AMT RDA) is earned by meeting the certifying body's eligibility requirements and passing its exams. Keeping it active means meeting that issuer's ongoing requirements and renewal limits.
- A state credential (registration, license, permit or certificate) is issued by your state dental board. State rules, including credential and supervision requirements, govern which duties you may legally perform there.
DANB's own exam outlines say its exams or certification must be recognized by the state for the duties concerned. That recognition can be one part of the state's requirements; it does not remove other conditions (GC outline, p. 9).
How your state changes the answer
There's no single national credential that authorizes every dental assisting duty in every state. The U.S. Bureau of Labor Statistics notes that states typically don't require a license for entry-level assistants, but many require training, registration or certification for duties such as radiography, and states that allow expanded functions regulate them (BLS, How to Become a Dental Assistant).
Some states accept a national credential as one way into their own process. Others don't use one at all. Three verified examples show how differently this works:
| State | How it works | Official source |
|---|---|---|
| Texas | Texas has a separate RDA/X-ray registration process. One qualifying route is a current DANB CDA plus passing the board's Jurisprudence Assessment within one year of applying. The board also requires a high school diploma or GED, fingerprints, hands-on BLS and an approved human trafficking prevention course. | Texas State Board of Dental Examiners |
| California | The Registered Dental Assistant is a state license. Since July 1, 2025, an active DANB CDA is one of the pathways to apply for it. You still need the required courses, BLS, background check, application and state Combined Written and Law and Ethics Examination. | Dental Board of California, RDA requirements; July 2025 pathway change |
| Florida | The Board of Dentistry doesn't license dental assistants. Its dental radiographer certification route requires at least 3 months of continuous on-the-job training under a Florida dentist's direct supervision, plus a board-approved course completed within 12 months after that training is completed. The board also lists formal-training alternatives for radiography qualification. | Florida Board of Dentistry, Dental Radiographer |
About the letters "RDA": AMT's Registered Dental Assistant is a national certification. Texas and California use "RDA" for state credentials. AMT says plainly that its RDA doesn't replace any state licensing requirement. When a job ad asks for an RDA, check which issuer it means.
Moving states? A current national certification moves with you, but state permission doesn't automatically transfer. Check your new state's rules for the duties you'll perform before you start.
DANB CDA at a glance
Preparing for GC, RHS and ICE? Use our free DANB CDA exam prep guide with an eight-week study plan and 22 original practice questions with sourced explanations.
| Exam | Questions | Time | Fee (standard / active military) | Eligibility |
|---|---|---|---|---|
| Radiation Health and Safety (RHS) | 75 | 60 min | $270 / $265 | None |
| Infection Control (ICE) | 75 | 60 min | $270 / $265 | None |
| General Chairside Assisting (GC) | 95 | 75 min | $270 / $265 | Pathway I, II or III + CPR |
| Full CDA exam (all three together) | 245 | 195 min | $450 / $425 | Pathway I, II or III + CPR |
| RHS/ICE, ICE/GC or RHS/GC combo | — | — | $375 / $365 | GC combos need GC eligibility |
Sources: CDA packet, pp. 3, 11, 15; CDA exam page; outlines for RHS, ICE and GC, p. 2.
How the process works:
- Pick your exam selection and gather your evidence for your pathway: a diploma or transcript, the signed work experience form, or your degree or license. If you need testing accommodations, request them with your application.
- Apply and pay through DANB. Fees include a $75 application fee that isn't refundable. Cancel your original authorized testing window for a partial refund and DANB retains that $75 plus a $40 cancellation fee—$115 total. You must cancel any appointment on time and request the refund before the window ends; canceling the appointment alone does not request a refund (cancellation instructions).
- Schedule and test within 60 days of approval. You can request one new 60-day window for $60 per exam, within 60 days after the original window ends; any existing appointment must also be canceled on time (new-window instructions).
- Get results in your DANB account within 1–3 business days.
- Pass RHS, ICE and GC within five years to earn the CDA. Then complete any separate state application your duties require.
A few rules that trip people up:
- Scoring: DANB uses computer adaptive testing, so questions get harder or easier based on your answers, and you can't skip a question and come back to it (DANB). Scores run from 100 to 900, and 400 passes. DANB's outlines note the average candidate answers about half the questions correctly, so a "percent correct" target doesn't apply.
- ID: For a test-center appointment, bring one original, current, government-issued photo ID with a signature. Your name must meet DANB's matching rules: the middle name is optional, and a matching middle initial is accepted. If your ID doesn't meet the rules, you'll be turned away and the appointment counts as missed (2026 Candidate Handbook, p. 9).
- Failing: There's no limit on retakes, but each retake is a new application at the full fee. Some states require extra education after failed attempts (Handbook, p. 4).
- Language: RHS and ICE are also offered in Spanish. For online-proctored appointments, the greeter and proctor communicate in English (DANB Spanish exams).
What each exam covers (official domain weights)
Use these to decide where your study hours go. The percentages are each domain's share of that exam's questions, not a measure of difficulty.
RHS (outline effective March 12, 2025; digital radiography only, with no film concepts tested since July 7, 2022)
- Purpose and Technique: 50%
- Radiation Characteristics and Protection: 25%
- Infection Prevention and Control: 25%
ICE (outline effective March 12, 2025)
- Prevention of Disease Transmission: 20%
- Prevention of Cross-contamination: 34%
- Process Instruments and Devices: 26%
- Occupational Safety and Administration Protocols: 20%
GC (outline effective July 1, 2022)
- Evaluation: 17%
- Patient Management and Administration: 17%
- Chairside Dentistry: 50%
- Dental Materials: 16%
What it costs, and how combining exams changes the total
How you combine the exams changes the total. These totals add up DANB's 2026 standard fees for first attempts, without retakes (CDA packet, pp. 11, 15; NELDA packet, p. 11).
| Plan | Exams you buy | Total |
|---|---|---|
| Eligible now, test all at once | Full CDA exam | $450 |
| Not yet eligible for GC: take RHS/ICE now, add GC later | RHS/ICE ($375) + GC ($270) | $645 |
| NELDA first, then CDA once eligible for GC | NELDA ($400) + GC ($270), with RHS/ICE passes still within the CDA's five-year period | $670 |
| Buy every exam separately | RHS + ICE + GC ($270 × 3) | $810 |
| AMT RDA (a separate credential) | Application, exam and first annual fee | $150 |
If you're already eligible for GC, testing all three at once saves $195 over the RHS/ICE-then-GC route and $360 over buying each exam alone. If you're not eligible yet, RHS/ICE can be a sensible start when those exams meet your state requirement or CDA goal, because those passes count toward the CDA for five years. NELDA is not a required step toward CDA, and it does not replace GC eligibility.
Exam fees aren't the whole bill. Also budget for:
- Program tuition and supplies, if you're going the education route
- A hands-on CPR, BLS or ACLS course from an accepted provider
- Any state application, training or radiography course fees
- Retakes, since each one is billed at the full fee
- Annual renewal (see "Keeping your certification" below)
NELDA: DANB's entry-level certification
The National Entry Level Dental Assistant (NELDA) certification is made up of three exams: RHS, ICE and Anatomy, Morphology and Physiology (AMP). The full NELDA exam is $400 ($380 active military). AMP alone is $245. If you need all three exams and qualify for NELDA, buying RHS/ICE ($375) and then AMP ($245) costs $620, or $220 more than the combined NELDA exam.
You don't send eligibility documents to sit the NELDA exams. You send them after you've passed all three within three years, and they must show you meet one of four pathways (2026 NELDA packet, pp. 3–4):
- You completed a DANB-accepted dental assisting program that is not CODA-accredited, at a postsecondary institution accredited by a U.S. Department of Education-recognized organization, and you have a high school diploma or equivalent.
- You graduated from a U.S. Department of Labor Job Corps dental assisting program.
- You completed a dental assisting program of at least one semester at a high school or high-school-level technical school recognized by the state Department of Education, and the program appears on DANB's accepted-program list.
- You have 300 to 3,000 hours of dental assisting work, earned over 2 months to 3 years and verified by a licensed dentist, plus a high school diploma or equivalent.
All four pathways also require DANB-accepted hands-on CPR, BLS or ACLS, current when you apply for the NELDA certification.
Two limits matter before you pay. If you've completed a CODA-accredited program or have more than 3,000 hours of work, DANB won't award NELDA and points you to the CDA instead. And NELDA can be renewed no more than three times, so you can hold it for up to four years. It's a stepping stone, not a long-term credential.
AMT RDA: the other national certification
American Medical Technologists' Registered Dental Assistant, RDA(AMT), costs $150, which covers the application, the exam and the first annual fee. You take the exam at your school (if it partners with AMT) or at a Pearson VUE test center (AMT RDA).
You need valid hands-on CPR plus one of these routes:
| AMT route | Requirement |
|---|---|
| Education | Graduated within the last 4 years, or scheduled to graduate, from a qualifying dental assisting program; the program or institution must have AMT-accepted accreditation or AMT approval |
| Competency & work-based learning | Within the last 4 years, an AMT-approved hybrid program (720 total hours with at least 160 externship hours, or an approved 500-hour course with at least 160 externship and 340 didactic hours) plus a documented competency evaluation |
| Military | A military dental assisting program within the last 4 years, plus 1 year (2,080 hours) of dental assisting work within the last 5 years |
| Work experience | 3 years (6,240 hours) as a dental assistant within the last 5 years, plus a high school diploma or GED |
| Instructor | Currently teaching in a qualifying dental assisting program, with completed instruction in a related healthcare discipline; either at least 3 years of full-time teaching within the last 5 years, or more than 1 but less than 3 years of full-time teaching plus 2 years (4,160 hours) of qualifying clinical experience within the last 5 years |
For the education and instructor routes, AMT accepts qualifying program or institutional accreditation by a U.S. Department of Education- or CHEA-approved agency, or AMT approval. Program content and route-specific documentation must also meet AMT's requirements. AMT accepts qualifying part-time equivalents for work and teaching experience. For the shorter instructor route, you must document at least one teaching year within the past five years.
The RDA exam has 210 questions: Office Assisting Skills (20), Dental Sciences (70), Clinical Procedures (68) and Dental Imaging (52) (AMT RDA content outline). Unlike DANB's current RHS exam, AMT's outline still lists both film and digital radiography.
CDA or RDA(AMT)? If your state names a DANB exam or the CDA in a route you plan to use, follow that exact requirement; a component-exam requirement does not automatically mean you need the full CDA. Texas and California offer CDA-based routes alongside other pathways. If RDA(AMT) meets your state and employer requirements, its initial certification fee is lower. Either way, check your state first.
Before you enroll or apply
Work through this list before you pay a school or an exam fee. Avoid buying a course or exam that satisfies a different requirement than the one you actually face.
- Name the state and the duties. Write down where you'll work and whether the job includes x-rays or expanded functions, then find that state's rules on DANB's state requirements page and the state board's site.
- Name the credential and its issuer. "Certified" or "RDA" isn't enough. Confirm whether an employer or board means DANB's CDA, AMT's RDA, or a state credential.
- Check the program, not just the school. If your route depends on a CODA-accredited program, look up that specific program in CODA's program directory. A college's general accreditation is a different thing.
- Collect your route evidence. That means a diploma or transcript, a dentist-signed work experience form, or your license or degree. Keep any earlier DANB exam results and their dates together, since passes count for five years toward the CDA.
- Get the right CPR card. For DANB, it must come from a DANB-accepted provider and include a hands-on skills test. CDA/GC applicants need it current through their testing window; NELDA applicants need it current when applying for certification. AMT also requires in-person CPR demonstration.
- Build the full budget. List exam fees separately from tuition, CPR, state fees, travel, retakes and renewal. Mark anything you don't know yet as unknown rather than zero.
- Match your ID to your account. Your DANB account name must meet the handbook's ID-matching rules, including its middle-name exceptions. If you need accommodations, ask with your application, before authorization.
- Pick one next official action. Request a missing document, finish a required course, or submit the right application. Track national and state steps separately.
Free starter practice: 12 questions across RHS, ICE and GC
Original, unofficial practice written by Castleport Test Prep. These are not DANB or AMT exam questions, and your score here doesn't predict a scaled score.
Q1 (RHS). A premolar bitewing shows the contacts between the premolars overlapping, so you can't see the interproximal spaces. What's the most likely cause?
Reveal answer
C. Incorrect horizontal angulation. Horizontal angulation is the side-to-side direction of the beam. When the central ray isn't directed through the contacts, the image shifts and the proximal surfaces overlap. Vertical angulation errors change tooth length (A and B). An uncovered receptor causes a cone cut, which is a white unexposed area on a digital image (D). (Dentalcare CE559)
Q2 (RHS). Using the bisecting-angle technique, you take a maxillary canine periapical with the patient and receptor correctly positioned. The tooth looks much longer than it really is. What should you change?
Reveal answer
B. Increase the vertical angulation. Elongation comes from too little vertical angulation, so the fix is to increase it. Decreasing the angle (A) makes this error worse; too much vertical angulation instead foreshortens the tooth. C fixes overlapped contacts, not length. Reducing exposure time (D) does not correct the projection geometry. (Dentalcare CE559)
Q3 (RHS). A digital image has a white, unexposed area with a curved border along one side. What happened?
Reveal answer
A. Cone cut. When the x-ray beam doesn't cover the whole receptor, part of the image is never exposed. A round collimator produces a curved edge to the unexposed area, while a rectangular collimator produces a straight edge. Movement (B) blurs the image, and horizontal errors (D) overlap contacts. Overexposure (C) does not create a sharply bounded unexposed area; digital processing can also alter displayed brightness. (Dentalcare CE559, Technique Errors and Miscellaneous Errors)
Q4 (RHS). Which habit best applies the ALARA principle (As Low As Reasonably Achievable)?
Reveal answer
B. ALARA means keeping radiation exposure as low as reasonably achievable while still getting a diagnostic image. FDA and ADA guidance calls for justified imaging and technique that provides the needed diagnostic information with the lowest reasonable exposure. Applying that principle, preventing avoidable retakes reduces additional exposure. A and C add exposure without need, and D skips the medical and dental history used to decide whether imaging is appropriate. (FDA, Medical X-ray Imaging; ADA, X-rays/Radiographs)
Q5 (ICE). According to CDC guidelines for dental settings, how often should each sterilizer be checked with a biological indicator (spore test), at minimum?
Reveal answer
A. At least weekly. CDC calls biological indicators the most accepted way to monitor sterilization, because they show that highly resistant spores were killed, and recommends using them on each sterilizer at least weekly. A chemical indicator belongs inside every package, but chemical indicators (C) don't prove sterility. Monthly or yearly testing (B, D) is too infrequent. A biological indicator is also required for every load containing implantable items. (CDC, Sterilization Monitoring)
Q6 (ICE). A stainless-steel mouth mirror touches the patient's oral mucosa and tolerates heat. How should it be classified and processed?
Reveal answer
B. Semicritical; heat sterilize. Items that touch mucous membranes are semicritical. CDC says most semicritical dental items tolerate heat, so they should be heat sterilized. Intermediate-level disinfection is not enough for this heat-tolerant mouth mirror, which rules out C. Critical items (A) penetrate soft tissue or bone, and noncritical items (D) touch only intact skin. (CDC, Sterilization and Disinfection)
Q7 (ICE). The dentist will give a second injection to the same patient with the same anesthetic needle during the same procedure. How should the needle be recapped between injections?
Reveal answer
B. CDC and the OSHA Bloodborne Pathogens Standard both rule out two-handed recapping (A). When a procedure requires recapping, it must be done with a one-handed technique or a mechanical device. OSHA permits recapping or bending a contaminated needle only when no feasible alternative exists or a specific procedure requires it; bending merely to prevent an injury (C) is not justified here. Passing an unsheathed needle (D) should be avoided because of the injury risk. (OSHA 29 CFR 1910.1030(d)(2)(vii), via eCFR; CDC, Standard Precautions—Sharps Safety)
Q8 (ICE). A new dental assistant will have occupational exposure to blood and saliva. Under the OSHA Bloodborne Pathogens Standard, when must the employer make the hepatitis B vaccination available?
Reveal answer
B. OSHA requires the vaccine series to be made available after the required training and within 10 working days of initial assignment, at no cost to the employee. Exceptions apply if the employee has already completed the vaccination series, is immune, or cannot receive it for medical reasons. Waiting for an exposure (A) defeats the purpose, cost-sharing (C) isn't allowed, and the employer can't make prescreening a prerequisite (D). (OSHA 1910.1030(f)(1)(ii)(A), (f)(2)(i)–(ii))
Q9 (GC). Using the Universal Numbering System, which tooth is #8?
Reveal answer
B. The Universal system starts at #1, the maxillary right third molar, and counts across the maxillary arch to #16. Tooth #8 is the maxillary right central incisor, and #9 is the maxillary left central incisor (A). The mandibular right central incisor is #25 (C), and the maxillary right third molar is #1 (D). (ADA Universal Tooth Designation System, pp. 2–3)
Q10 (GC). An adult patient who is not pregnant briefly faints while sitting upright after seeing the anesthetic syringe. Treatment is stopped. The dentist assesses the episode as a simple faint, and the patient is now fully alert, breathing normally, and has no injury or breathing difficulty. After emergency help is called per office protocol, which position is appropriate while the patient recovers?
Reveal answer
B. Supine with the feet slightly elevated. AHA and American Red Cross guidance says that raising the feet slightly may be reasonable after a simple faint when there is no injury and the patient is alert and breathing normally. Sitting upright (A, C), or leaving this patient upright (D), is not the preferred recovery position in this scenario. Continue monitoring; if raising the feet causes discomfort or worsens symptoms, return them to a flat position. (2024 AHA and American Red Cross First Aid Guidelines, §§5.1–5.2)
Q11 (GC). An adult patient with diabetes becomes shaky and sweaty. Treatment is stopped, and the glucose meter reads 64 mg/dL. The patient is fully alert and can swallow safely. Following the dentist's direction and office protocol, what's the appropriate first step?
Reveal answer
A. The measured glucose is below 70 mg/dL. CDC's 15-15 rule is to give 15 grams of fast-acting carbohydrate, wait 15 minutes, and recheck. If glucose is still below 70 mg/dL, repeat until it reaches at least 70 mg/dL, then eat a snack or meal containing carbohydrate and protein. Chocolate (B) is high in fat, which slows sugar absorption. Insulin (C) would lower blood sugar further, and continuing treatment (D) ignores the emergency. AHA and American Red Cross guidance calls for emergency services if symptoms do not improve within 10 minutes after oral glucose, or if the patient cannot swallow safely, has a seizure or becomes unresponsive. That symptom-based escalation is separate from the 15-minute glucose recheck; do not give anything by mouth if the patient is not fully alert or cannot swallow safely. (CDC, Treatment of Low Blood Sugar; 2024 AHA and American Red Cross First Aid Guidelines, §6.7)
Q12 (GC). Under the OSHA Bloodborne Pathogens Standard, how is saliva classified during dental procedures?
Reveal answer
C. OSHA's definition of other potentially infectious materials specifically includes saliva in dental procedures, whether or not blood is visible. OSHA requires universal precautions for blood and OPIM. CDC's broader Standard Precautions apply to every patient, not only those with a known infection (D). (OSHA 29 CFR 1910.1030(b), (d)(1), via eCFR; CDC, Standard Precautions)
Using your results:
- Missed an RHS question? Review angulation, image errors and radiation protection. Purpose and Technique is half of the RHS exam.
- Missed an ICE question? Review CDC's dental infection-control guidance and the OSHA Bloodborne Pathogens Standard, focusing on sterilization, sharps safety and occupational protections.
- Missed a GC question? Review tooth numbering, recognition and response to medical emergencies, and infection-control precautions—the topics sampled here from Evaluation and Patient Management and Administration.
Twelve questions is a quick check on where to start studying, not a readiness test. This small set does not cover every domain or mirror the official domain weights. When you're ready to study in depth, use the official RHS, ICE and GC outlines and their reference lists as your checklist.
Keeping your certification
All three national credentials have yearly requirements. Renewing a national certification doesn't renew a state license, which has its own rules.
| Credential | What renewal takes |
|---|---|
| DANB CDA (one certification) | Every year: 12 continuing dental education (CDE) credits, including at least 1 on OSHA's Bloodborne Pathogens Standard and 2 in infection prevention and control; a current hands-on CPR, BLS or ACLS card; and a $75 fee. Holding more DANB certifications raises the total (18 credits and $90 for two). |
| DANB NELDA | Every year: 6 CDE credits, including at least 3 in infection control (1 of them on bloodborne pathogens); current hands-on CPR, BLS or ACLS; and a $50 fee. NELDA can be renewed only three times and can't be reinstated if you fail to renew by the end of its three-month grace period. |
| AMT RDA | A $75 annual fee and 30 points through AMT's Certification Continuation Program (CCP) over each three-year cycle. AMT suggests logging about a third of the points each year. |
For DANB, CPR, BLS or ACLS is an additional requirement and does not count toward the CDE total. DANB gives a three-month grace period after expiration, with a $20 late fee; you are still considered certified during that period. After that you're no longer certified and may have to retest to get the CDA back. DANB audits some renewals, so keep proof of CDE and CPR for two years. Sources: DANB 2026 Recertification Requirements, pp. 2–5, 9; NELDA Recertification Requirements; AMT, Maintain Certification.
Common questions
Do I have to be certified to work as a dental assistant?
It depends on your state and the duties you'll perform. Many states don't require a license for entry-level duties but do require approved training, registration or certification for radiography or expanded functions. Look up your state on DANB's state requirements page and confirm with your state dental board before you enroll or apply.
How long does it take?
It depends on your route. BLS says many dental assisting programs take about a year, and two-year associate degree programs are less common (BLS). On the CDA's work route, the 3,500 hours must be spread over at least two years. Once DANB approves your application, you have 60 days to test, and results post within 1–3 business days. All three component passes must fall within a five-year period. State applications add their own processing time; Texas, for example, gives a typical estimate of 3–4 weeks for a complete application, which can take longer.
Can I get certified online?
Partly. Coursework can be online, but an online course isn't automatically accepted for your credential or state, so check the specific program. DANB's online-exam information and outlines say the individual RHS, ICE and GC exams can be taken by online remote proctoring or at a test center. DANB's page for the combined CDA exam lists test-center delivery, so check your options before you book. CPR must include a hands-on skills test for both DANB and AMT, and some state routes, such as Florida's radiographer certification, require supervised on-the-job training.
How hard is the DANB exam?
DANB doesn't publish a percent-correct pass mark. Because the exam is adaptive, DANB says the average candidate answers around half the questions correctly, and passing requires a scaled score of 400 or higher on each exam. The fairest way to judge difficulty is by your weakest domain. If Chairside Dentistry (50% of GC) or Purpose and Technique (50% of RHS) is shaky, start there.
Is the CDA worth it?
DANB's 2020–2021 Dental Assistants Salary and Satisfaction Survey found that CDA holders reported earning just over $2 more per hour than dental assistants overall (DANB). That's DANB's own self-reported survey, and it doesn't prove the certification caused the difference. The stronger reason is practical: in states that use DANB exams, the CDA can count toward state credentials, as the Texas and California examples show.
What happens if I fail one exam?
For the CDA, you keep any exams you've passed, as long as you pass all three within five years. Reapply for the failed exam at the full fee; there's no retake limit. If you think there was a scoring error, DANB offers hand scoring for a fee. Submit the required request and payment promptly when your results arrive; the Candidate Handbook explains the short request deadline.
Sources
The eligibility, fee, exam, renewal, state-example and practice-answer claims on this page were checked against the sources below on October 23, 2026.
- DANB, 2026 CDA Application Packet (updated May 13, 2026): pathways, five-year rule, fees, CPR, testing window
- DANB, 2026 NELDA Application Packet (updated May 15, 2026): NELDA pathways, fees, limits
- DANB, 2026 Candidate Handbook (updated June 22, 2026): retakes, results, ID, online testing, hand scoring
- DANB exam outlines: RHS (effective March 12, 2025), ICE (effective March 12, 2025), GC (effective July 1, 2022)
- DANB, CDA exam page, CPR providers, state requirements, online-proctored exams and Spanish exams
- DANB, 4 important details to know about DANB exams (January 10, 2024); forms for canceling a testing window, requesting a new window and requesting hand scoring
- DANB, 2026 Recertification Requirements and NELDA Recertification Requirements (both updated May 15, 2026)
- AMT, Dental Assistant (RDA), RDA content outline and Maintain Certification
- Texas State Board of Dental Examiners, RDA X-Ray Certification; Dental Board of California, RDA requirements and July 2025 pathway change; Florida Board of Dentistry, Dental Radiographer
- CODA program directory; BLS Occupational Outlook Handbook, Dental Assistants (modified August 27, 2026)
- Practice-question sources: CDC Sterilization Monitoring, Sterilization and Disinfection, Standard Precautions and Treatment of Low Blood Sugar; OSHA 29 CFR 1910.1030 via eCFR; 2024 AHA and American Red Cross First Aid Guidelines; Dentalcare.com CE559 Technique Errors and Miscellaneous Errors; FDA, Medical X-ray Imaging; ADA X-rays/Radiographs and Universal Tooth Designation System
Castleport Test Prep is an independent exam prep publisher. We are not affiliated with, endorsed by, or approved by the Dental Assisting National Board (DANB), American Medical Technologists (AMT), or any state dental board cited here. Exam and credential names identify their subjects; trademarks belong to their respective owners. The practice questions on this page are original and are not official exam questions.