DANB CDA Exam Prep: 8-Week Study Plan and 22 Practice Questions
The DANB CDA is built from three component exams: General Chairside Assisting (GC), Radiation Health and Safety (RHS) and Infection Control (ICE). Taken together, that's 245 multiple-choice questions in 195 minutes, and you need a scaled score of 400 on each exam, not on the total.
Your 8-week CDA study plan
Built for about 6–8 hours a week, with one current dental assisting textbook plus the free official documents linked in each row. DANB says many test-takers spent at least 1–2 months studying, so eight weeks sits in that range. We start with infection control on purpose: it shows up in two of the three exams (more on that below).
| Week | Focus | Outline areas | What to study and do |
|---|---|---|---|
| 1 | Infection control foundations | ICE I (20%), ICE II (34%) | Chain of infection, standard precautions, hand hygiene, PPE selection and the order you put it on and take it off, surface barriers, disinfectant levels, dental unit waterlines, disinfecting impressions and appliances, waste disposal. Read CDC's Summary of Infection Prevention Practices in Dental Settings. |
| 2 | Instrument processing and OSHA | ICE III (26%), ICE IV (20%) | Instrument workflow from transport to storage, packaging, loading the sterilizer, mechanical/ |
| 3 | Radiation physics and protection | RHS II (25%), RHS III (25%) | kVp, mA and exposure time; primary vs. scatter radiation; how radiation affects cells; units (gray, sievert, roentgen, rem); ALARA; operator protection by barrier, position and distance; collimation; infection control for sensors and x-ray equipment. |
| 4 | Imaging technique | RHS I (50%) | Purpose of each image type (periapical, bitewing, full mouth series, occlusal, panoramic, cephalometric, CBCT); what makes an image diagnostically acceptable; paralleling, bisecting and panoramic technique; fixing errors (angulation, cone-cuts, exposure, movement); mounting, landmarks, radiopaque vs. radiolucent. Digital only. Skip film processing. |
| 5 | Evaluation and administration | GC I (17%), GC II (17%) | Tooth anatomy and morphology, Universal numbering for permanent and primary teeth, charting, vital signs, medical history, medical emergencies; patient education, OSHA/CDC/HIPAA rules, standard of care, inventory, equipment and emergency-kit maintenance. |
| 6 | Chairside dentistry, part 1 | GC III (50%) | Four-handed dentistry, treatment room and tray setups, seating and positioning, instrument transfer, dental dam and moisture control, restorative procedures (composite, amalgam, crown and bridge), matrix bands, temporary restorations, anesthesia setup. |
| 7 | Chairside dentistry, part 2, and materials | GC III, GC IV (16%) | Oral surgery (extractions, implants, dry socket, post-op care), nitrous oxide/oxygen, sealants, coronal polishing, fluoride, whitening; impression materials (alginate, elastomerics), cements, composites, bonding agents, liners and bases, gypsum, waxes, acrylics. |
| 8 | Mixed review and logistics | All three exams | Timed mixed sets at about 48 seconds per question. Rework every logged miss until you can explain the rule out loud. Confirm your ID, CPR card and test location (see the final-week checklist below). |
Every week, do the same three things: learn the week's topics, test yourself with 20–30 mixed questions without looking anything up, and log every miss by exam and domain so week 8 has something to work from.
If you're taking RHS and ICE first: do weeks 1–4, sit RHS and ICE, then do weeks 5–8 before GC. You have five years to pass all three.
If you only have 4 weeks: pair the weeks (1+2, 3+4, 5+6, 7+8) and roughly double your weekly hours. Keep every topic; shorten the sessions, not the list.
If you need 12 weeks (for example, you qualify through work experience but haven't done much radiography or sterilization): give weeks 4 and 6 two weeks each, and add a cumulative review week after week 4 and after week 8.
This is our editorial plan, built from DANB's published outlines and weights. It isn't a DANB requirement, and no plan guarantees a result. DANB also publishes its own free study guide plans for RHS, ICE and GC.
What the DANB CDA exam covers
| Exam | Questions | Time | Current domain weights |
|---|---|---|---|
| GC | 95 | 75 min | Evaluation 17%; Patient Management and Administration 17%; Chairside Dentistry 50%; Dental Materials 16% |
| RHS | 75 | 60 min | Purpose and Technique 50%; Radiation Characteristics and Protection 25%; Infection Prevention and Control 25% |
| ICE | 75 | 60 min | Prevention of Disease Transmission 20%; Prevention of Cross-contamination 34%; Process Instruments and Devices 26%; Occupational Safety and Administration Protocols 20% |
| CDA (all three together) | 245 | 195 min | You must pass GC, RHS and ICE; the components can also be taken separately |
Sources: DANB CDA exam page and the current GC (effective July 1, 2022), RHS and ICE outlines (both effective March 12, 2025).
DANB says every candidate taking a particular exam receives the same percentage of questions from each domain. Use those percentages to prioritize study time, not to convert the published question totals into a predicted number of scored questions: DANB also includes a small number of unidentified, unscored pretest questions.
Three things stand out:
- Chairside Dentistry is GC's biggest domain at 50%. GC still has to be passed on its own, so don't let strong RHS or ICE practice crowd it out.
- Infection-control knowledge appears on two components. It is the whole ICE exam and also 25% of RHS, which is why the plan starts with infection-control foundations.
- You can't bank points across exams. A strong RHS score doesn't rescue a weak GC score, because each component needs its own passing scaled score of 400.
Practice questions: 22 original CDA questions with explanations
Answer each question before you read the explanation under it. The set covers all three exams (8 GC, 6 RHS, 8 ICE). Every answer links to the source that supports it.
These are original, unofficial practice questions written by Castleport Test Prep. They are not DANB exam questions. Your score on them is feedback on these 22 items only; it does not convert to DANB's scaled score.
Question 1 · GC — I. Evaluation
The dentist calls out a large cavity on the mandibular left first molar. Using the Universal Numbering System, which tooth do you chart?
Show answer
Answer: C. #19
Why: Universal numbering starts at #1, the maxillary right third molar, and runs across the upper arch to #16. It then drops to #17, the mandibular left third molar, and runs back to #32. Counting from #17: #17 is the third molar, #18 the second molar and #19 the first molar.
Why not the others: #3 is the maxillary right first molar, #14 is the maxillary left first molar, and #30 is the mandibular right first molar.
Source: American Dental Association: Universal Tooth Designation System value set
Question 2 · ICE — III. Process Instruments and Devices
How often should each dental sterilizer be checked with a biological indicator (spore test)?
Show answer
Answer: A. At least weekly, and with every load that contains an implantable device
Why: CDC recommends a spore test at least weekly for each sterilizer, plus a spore test for every load that contains an implantable device. Spores are harder to kill than ordinary microbes, so a negative spore test is direct evidence the cycle worked.
Why not the others: Monthly or yearly testing is far less often than CDC recommends. Chemical indicators check conditions inside a package; they don't replace routine spore testing.
Source: CDC: Best Practices for Sterilization Monitoring in Dental Settings
Question 3 · RHS — I. Purpose and Technique
On a premolar bitewing image, the contacts between neighboring teeth overlap, so you can't see the spaces between them. What caused this?
Show answer
Answer: B. Incorrect horizontal angulation
Why: Overlapped contacts mean the central ray was not aimed through the interproximal spaces. That is a horizontal angulation error. Fix it by directing the beam through the contacts.
Why not the others: Vertical angulation errors change how long the teeth look (foreshortening or elongation), not whether contacts overlap. An off-center PID causes a cone-cut, a clear unexposed area.
Source: DE 115: Dental Radiography, ch. 22.1 Receptor Exposure Errors
Question 4 · GC — III. Chairside Dentistry
During a composite restoration with the high-speed handpiece, which combination does the most to reduce the spatter and aerosol that reach the dental team?
Show answer
Answer: D. Dental dam plus high-volume evacuation
Why: CDC names dental dams and high-velocity evacuation as the work practices that minimize droplets, spatter and aerosol during treatment.
Why not the others: A saliva ejector and cotton rolls help with moisture, not spray. The air-water syringe itself creates spray. Patient eyewear protects the patient's eyes but does not reduce spatter.
Source: CDC: Guidelines for Infection Control in Dental Health-Care Settings, 2003
Question 5 · ICE — III. Process Instruments and Devices
At chairside you open a sterilization pouch. The external indicator changed color, but the internal chemical indicator did not. What should you do?
Show answer
Answer: B. Don't use the instruments; send them back to be reprocessed
Why: The external indicator only shows the package went through a cycle. The internal indicator shows the sterilizing agent actually reached the instruments inside. CDC says that if the right color change did not happen, don't use the instruments.
Why not the others: A negative weekly spore test doesn't prove this package was processed correctly. Surface disinfectant does not sterilize instruments.
Source: CDC: Best Practices for Sterilization Monitoring in Dental Settings; CDC: Guidelines for Infection Control in Dental Health-Care Settings, 2003
Question 6 · RHS — I. Purpose and Technique
On a maxillary periapical taken with the bisecting technique, the teeth look much longer than they really are. What happened, and what is the fix?
Show answer
Answer: C. Elongation from too little vertical angulation; increase the vertical angulation
Why: When vertical angulation is too flat (insufficient), the image of the tooth is longer than the real tooth. That is elongation. The fix is adequate vertical angulation.
Why not the others: Too-steep vertical angulation makes teeth look shorter (foreshortening). Horizontal errors overlap contacts. A cone-cut leaves a clear, unexposed area.
Source: DE 115: Dental Radiography, ch. 22.1 Receptor Exposure Errors
Question 7 · GC — I. Evaluation
Midway through a long appointment, a patient who takes insulin and skipped lunch becomes shaky, irritable and a little confused. She is alert, answers questions and can swallow. You have stopped the procedure and alerted the dentist. Under the dentist's direction, what is the most appropriate next step?
Show answer
Answer: D. Give a fast-acting sugar, such as 1/2 cup of regular fruit juice or glucose gel
Why: These signs fit low blood glucose (hypoglycemia). NIDDK advises 15 to 20 grams of glucose or fast carbohydrate, such as glucose gel or 1/2 cup of regular juice, then rechecking after 15 minutes. She is alert and can swallow, so sugar by mouth is safe.
Why not the others: Nothing by mouth is for someone who can't swallow or is unconscious; that situation calls for glucagon and 911. More insulin would push her glucose even lower. Oxygen does not raise blood sugar.
Question 8 · ICE — III. Process Instruments and Devices
A routine spore test comes back positive. The sterilizer's mechanical readings and the chemical indicators were normal. What is the first step?
Show answer
Answer: A. Take the sterilizer out of service, review the operating procedures and repeat the spore test right away
Why: CDC: remove the sterilizer from service, review procedures, recall and quarantine any implantable items, and repeat the spore test right away using the same cycle. If the repeat is negative and procedures were correct, it can go back into service. If it is positive again, the sterilizer is repaired and must pass three consecutive fully loaded spore-test cycles.
Why not the others: A year-long recall isn't the first step; recalls reach back to the last negative test if the sterilizer is found to be failing. Ignoring the result is unsafe. Liquid sterilants are impractical for routine instruments and can't be verified with spore tests.
Source: CDC: Best Practices for Sterilization Monitoring in Dental Settings; CDC: Guidelines for Infection Control in Dental Health-Care Settings, 2003
Question 9 · RHS — II. Radiation Characteristics and Protection
If the distance from the x-ray source to a point is doubled, the beam intensity at that point becomes:
Show answer
Answer: B. One-fourth as strong
Why: The inverse square law says intensity is inversely proportional to the square of the distance. Twice the distance gives 1/(2 x 2) = 1/4 of the intensity.
Why not the others: One-half is the most common wrong answer; it forgets to square the distance. Moving away never increases intensity.
Source: Digital Radiographic Exposure, ch. 8 Radiographic Distances
Question 10 · GC — II. Patient Management and Administration
The dentist refers a patient to an oral surgeon for impacted third molars. The surgeon's office asks for the patient's radiographs and relevant treatment notes. Which statement about HIPAA's minimum necessary standard is accurate?
Show answer
Answer: D. It does not apply to disclosures to another provider for treatment
Why: HHS lists disclosures to, or requests by, a health care provider for treatment as an exception to the minimum necessary standard. The office still uses reasonable safeguards when it sends the records.
Why not the others: HHS lists several exceptions, so 'no exceptions' is wrong. The rule does not treat digital images differently in this way, and there is no single-image limit.
Question 11 · ICE — III. Process Instruments and Devices
A stainless-steel amalgam condenser touches the oral mucosa but does not penetrate tissue. How should it be processed between patients?
Show answer
Answer: C. Heat sterilization, because it is a heat-tolerant semicritical item
Why: Items that touch mucous membranes are semicritical. CDC says heat-tolerant semicritical items should be heat-sterilized. High-level disinfection is the minimum only for semicritical items that can't take heat.
Why not the others: Noncritical items touch only intact skin, so calling it noncritical misclassifies it. Semicritical items can be sterilized, and most should be. Soap and water cleans but does not kill microbes reliably.
Source: CDC: Guidelines for Infection Control in Dental Health-Care Settings, 2003
Question 12 · RHS — II. Radiation Characteristics and Protection
Which unit expresses absorbed dose, the energy deposited per unit mass of tissue?
Show answer
Answer: A. Gray (Gy)
Why: The gray is the SI unit of absorbed dose: 1 Gy equals 1 joule per kilogram, or 100 rad.
Why not the others: The sievert is the SI unit for dose equivalent (equivalent and effective dose). The roentgen measures exposure, meaning ionization in air. The rem is the older unit of dose equivalent (1 Sv = 100 rem).
Source: National Research Council (1999), Radiation Quantities and Units, Definitions
Question 13 · GC — IV. Dental Materials
You take a conventional alginate impression for study models, and the manufacturer gives no extended-pour storage instruction. Which handling choice best protects dimensional accuracy?
Show answer
Answer: D. Pour it as soon as practical and follow the manufacturer's storage directions if a delay is unavoidable
Why: Traditional irreversible hydrocolloid impressions are generally most accurate when poured promptly. Their dimensions can change during storage, while some extended-pour formulations are designed to tolerate longer delays. The material's own instructions control when delayed pouring is permitted.
Why not the others: Immersion or prolonged open-air storage can change an alginate impression's dimensions, and simply waiting does not improve accuracy. Extended-pour products are the exception, not a reason to assume every alginate can sit for hours.
Question 14 · ICE — II. Prevention of Cross-contamination
For routine (nonsurgical) care, what water quality should treated dental unit water meet?
Show answer
Answer: B. 500 CFU/mL or less of heterotrophic water bacteria
Why: CDC recommends treating waterlines to meet the EPA drinking-water standard of 500 colony-forming units per milliliter or less, and monitoring as the equipment manufacturer recommends. If a test is higher, treat the unit and retest.
Why not the others: 5,000 and 50,000 CFU/mL are far above the standard. Sterile water or saline is for surgical procedures, delivered by a system that bypasses the dental unit.
Question 15 · RHS — I. Purpose and Technique
A periapical image has a clear, unexposed area with a straight edge along one side. A rectangular PID and a beam-alignment device were used. What is the most likely cause?
Show answer
Answer: A. A cone-cut, because the PID was not lined up with the aiming ring
Why: A cone-cut shows up as a clear, unexposed area. With a rectangular PID, its edge is straight. Fix it by centering the beam over the receptor and keeping the PID flush and aligned with the aiming ring.
Why not the others: Overexposure makes the image too dark, not clear. Horizontal errors overlap contacts. Movement blurs the image.
Source: DE 115: Dental Radiography, ch. 22.1 Receptor Exposure Errors
Question 16 · GC — III. Chairside Dentistry
The dentist will give a second injection with the same needle in a few minutes. What should happen to the syringe in between?
Show answer
Answer: C. Recap it with a one-handed scoop technique or a recapping device
Why: CDC: when one needle is used for several injections, recap it between injections with a one-handed technique or use a device with a resheathing mechanism.
Why not the others: Two-handed recapping points the needle at a hand. An unsheathed syringe on the tray invites a stick, and CDC says not to pass a syringe with an unsheathed needle. Needles should never be bent or broken.
Source: CDC: Guidelines for Infection Control in Dental Health-Care Settings, 2003
Question 17 · ICE — II. Prevention of Cross-contamination
After a procedure, there is visible blood on a blood pressure cuff, a noncritical item that touches only intact skin. After cleaning it, what should you use?
Show answer
Answer: D. An EPA-registered hospital disinfectant with a tuberculocidal claim (intermediate level)
Why: CDC: when a noncritical item is visibly contaminated with blood, use an EPA-registered hospital disinfectant with a tuberculocidal claim, which is intermediate-level.
Why not the others: Low-level disinfectant is enough only when the item isn't visibly bloody. Glutaraldehyde-type chemicals are highly toxic and meant for heat-sensitive semicritical items, not general surfaces. Hand rub is for skin.
Source: CDC: Guidelines for Infection Control in Dental Health-Care Settings, 2003
Question 18 · RHS — II. Radiation Characteristics and Protection
A patient asks why you take only the images the dentist prescribed and keep the x-ray beam small. Which principle are you following?
Show answer
Answer: B. ALARA
Why: ALARA means 'as low as reasonably achievable': making every reasonable effort to keep exposure as far below the limits as is practical. DANB's RHS outline lists ALARA and collimation (restricting beam size) under radiation protection.
Why not the others: The inverse square law describes how distance changes intensity. SLOB is for locating objects on images. Paralleling is a technique for placing the receptor and aiming the beam.
Source: National Research Council (1999), Radiation Quantities and Units, Definitions; DANB RHS Exam Outline (eff. 03/12/2025)
Question 19 · GC — IV. Dental Materials
You are hand-mixing polyvinyl siloxane (PVS) putty for a crown impression. Which glove type can interfere with the material's setting?
Show answer
Answer: A. Latex gloves
Why: CDC notes that latex gloves can interfere with the setting of vinyl polysiloxane impression materials, while synthetic vinyl gloves apparently do not.
Why not the others: Vinyl gloves are the ones CDC reports as not affecting the set. Glove material does matter, and sterility is not the issue.
Source: CDC: Guidelines for Infection Control in Dental Health-Care Settings, 2003
Question 20 · ICE — IV. Occupational Safety and Administration Protocols
You stick your gloved finger with a used anesthetic needle. What should you do first?
Show answer
Answer: C. Wash the wound with soap and water, then report the exposure immediately
Why: CDC: wash puncture wounds with soap and water and report the exposure right away, because some follow-up treatment works only if it starts promptly.
Why not the others: There's no evidence squeezing the wound helps, and bleach or injected antiseptics are not recommended. Waiting until the end of the day delays care that may be time-sensitive.
Source: CDC: Guidelines for Infection Control in Dental Health-Care Settings, 2003
Question 21 · GC — I. Evaluation
A 7-year-old's chart notes occlusal decay on tooth B. Which tooth is that?
Show answer
Answer: B. Primary maxillary right first molar
Why: Primary teeth are lettered A through T. Lettering starts with A, the maxillary right second molar, so B is the maxillary right first molar.
Why not the others: A is the maxillary right second molar. The mandibular right first molar is S. Permanent teeth use numbers, not letters.
Source: American Dental Association: Universal Tooth Designation System value set
Question 22 · ICE — I. Prevention of Disease Transmission
Before a routine exam, your hands are not visibly dirty. Which approach follows CDC guidance?
Show answer
Answer: D. Use an alcohol-based hand rub and let your hands dry completely before putting on gloves
Why: CDC: if hands are not visibly soiled, an alcohol-based hand rub is adequate. Do hand hygiene right before gloving, and dry your hands fully, because hands still wet with rub raise the risk of glove perforation.
Why not the others: Gloves don't replace hand hygiene. Gloves are single-use, and washing them can create tiny holes that let liquid through (wicking).
Source: CDC: Guidelines for Infection Control in Dental Health-Care Settings, 2003
How to use your results
Count your misses by exam, not just your total. If most of them landed in one exam, move that exam's weeks earlier in your plan or give them extra time. A miss teaches you most when you can explain why the right answer is right and why your answer wasn't; that's why every explanation above covers both.
For a feel of the real screens and navigation, DANB offers a free demo exam on its Prepare for Exams page.
How the CDA exam is scored
DANB exams use computer adaptive testing (CAT). When you answer correctly, the next question tends to be harder. Your result depends on the difficulty of the questions you get right, not on a percentage. DANB says the average candidate answers around 50% of questions correctly (RHS outline, p. 2).
- Scores are reported on a scaled score of 100 to 900. You need 400 to pass each exam (GC outline, "How exams are scored").
- A scaled score is not a number correct or a percent correct, and you're not graded against other test-takers.
- You must answer every question to get a pass/fail result (Candidate Handbook, p. 14).
- Results post to your online DANB account within 1–3 business days. Passed results are also mailed within 2–4 weeks (Handbook, p. 14).
Don't treat a run of difficult questions as evidence that you're failing. DANB explains that adaptive exams present questions at or close to your ability level, which can make the test feel unusually hard even when the system is working as designed (DANB: Clearing up 5 common misconceptions about DANB exams).
Take all three together or one at a time?
You can take the full CDA exam in one sitting or take GC, RHS and ICE separately. Either way, you must pass all three within five years to earn the CDA (2026 CDA Application Packet, p. 3).
| Option | 2026 fee (standard / active military) | How you can test | Good fit if |
|---|---|---|---|
| Full CDA exam (GC + RHS + ICE together) | $450 / $425 | DANB's CDA page lists test-center testing | You're eligible for GC and ready for all three |
| RHS/ICE now, GC later | $375 + $270 = $645 / $365 + $265 = $630 | RHS, ICE and GC outlines each allow a test center or online proctoring | You don't qualify for GC yet, or you need RHS/ICE sooner for a job or state requirement |
| Any single exam | $270 / $265 | Test center or online | Spreading out cost and study, or retaking one exam |
Fees from the 2026 CDA Application Packet, pp. 11 and 15; they include a $75 nonrefundable application fee. DANB accepts 2026 applications through Dec. 31, 2026; check the current packet if you apply later. Delivery options from the CDA exam page and the three outlines.
Taking everything together saves money ($450 vs. $645 for the split route) but means one long session. RHS and ICE have no eligibility requirements, so you can take them before GC if you need those components sooner or do not yet qualify for GC.
What to study for each exam
General Chairside Assisting (GC): 95 questions, 75 minutes
Half of GC is Chairside Dentistry, so don't study it as four equal pieces (GC outline, pp. 2–6).
- Evaluation (17%): tooth anatomy, numbering and surfaces, occlusion, head and neck anatomy, charting, vital signs, health histories, and medical conditions that cause emergencies (fainting, allergic reactions, asthma, heart problems, diabetes).
- Patient Management and Administration (17%): managing anxious and pediatric patients, oral health education, records, OSHA, CDC and HIPAA rules, standard of care, your state dental practice act, inventory, and maintaining equipment and the emergency kit.
- Chairside Dentistry (50%): four-handed dentistry, room and tray setup, instrument transfer, dental dam and moisture control, restorative procedures, oral surgery, nitrous oxide/oxygen, and preventive procedures like sealants, coronal polishing and fluoride.
- Dental Materials (16%): alginates, elastomerics, waxes, amalgam, composites, cements, etchants, bonding agents, glass ionomers, sealants, temporaries, liners and bases, polishing agents, and lab materials.
Study procedures as sequences: what goes on the tray, in what order, and why. Some GC topics are expanded functions that only some states let assistants perform; the exam tests knowledge, not what your state allows you to do.
Radiation Health and Safety (RHS): 75 questions, 60 minutes
RHS tests digital radiography only. DANB says no film-based concepts have been tested since July 7, 2022 (RHS outline, p. 1). Skip film processing and darkroom chapters.
- Purpose and Technique (50%): what each image type is for, what makes an image diagnostically acceptable, paralleling, bisecting and panoramic technique, positioning, technique changes for tori or a shallow palate, fixing errors, sensor and PSP care, mounting and landmarks, and legal rules for keeping images.
- Radiation Characteristics and Protection (25%): what kVp, mA and time do, primary vs. scatter radiation, effects on cells and tissues, units of measurement, dose limits, ALARA, and protecting yourself and the patient.
- Infection Prevention and Control (25%): barriers, cleaning and disinfecting x-ray equipment, processing items used for imaging, hand hygiene and PPE during imaging.
On lead aprons: in 2024 the American Dental Association said lead abdominal aprons and thyroid collars are no longer recommended for patients during dental imaging, partly because they can block the beam and cause retakes. The same guidance says to follow all federal, state and local radiation rules, and DANB's RHS outline still lists "shielding" as a factor in radiation protection. For work and exam preparation, separate the current ADA recommendation from any state rule that still requires shielding.
Infection Control (ICE): 75 questions, 60 minutes
Cross-contamination (34%) and instrument processing (26%) make up 60% of ICE (ICE outline, pp. 2–4).
- Prevention of Disease Transmission (20%): how diseases spread, reviewing medical histories, hand hygiene, PPE, and limiting aerosols and spatter.
- Prevention of Cross-contamination (34%): cleaning and disinfecting treatment areas and labs, chemical disinfectants, surface barriers, tray setups, waterlines, evacuation lines and traps, disinfecting impressions and appliances, and waste disposal.
- Process Instruments and Devices (26%): the full instrument workflow, packaging, choosing and loading the sterilizer, keeping items sterile in storage, and choosing and reading sterilization monitors.
- Occupational Safety and Administration Protocols (20%): OSHA Bloodborne Pathogens and Hazard Communication standards, sharps safety and exposure follow-up, CDC guidelines, EPA and FDA rules, and keeping programs, logs and training records.
The ICE outline's main references are CDC's 2003 dental infection control guidelines, which CDC says still serve as the standard of practice, CDC's 2016 summary, and the OSHA standards.
Watch out for outdated prep material
- Film processing for RHS. Not tested since July 2022.
- An old GC blueprint. If a source describes GC as 120 questions in six parts, or says GC has no eligibility requirements, it's out of date. Today's GC is 95 questions in four domains and requires an eligibility pathway.
- Wrong exam length. The full CDA is 245 questions in 195 minutes. 75 minutes is GC alone.
- Old textbook editions. DANB allows older editions of its listed references if published within the past 7 years for GC and the past 5 years for RHS and ICE (see each outline's reference page).
- DANB gives you the acronym list during the exam (see each outline). Learn the concepts behind the acronyms instead of memorizing the list.
Final-week and exam-day checklist
- Re-open the three outlines and check off anything you never practiced.
- Retest your weakest exam with a fresh mixed set, then rework your miss log.
- Stop adding new material in the last 48 hours. Review misses, then rest.
- Check your ID. It must be a current, government-issued photo ID with a signature, and the name must match your DANB account exactly. Temporary IDs aren't accepted (Handbook, p. 9).
- Check your CPR card (for GC or the full CDA). It must be hands-on CPR, BLS or ACLS from a DANB-accepted provider and stay current through your whole 60-day testing window (Application Packet, p. 4).
- Know your testing setup. Online: no breaks, a private room with a closed door, a clear desk, and check-in no later than 15 minutes after your start time or the exam counts as missed. At a test center: breaks need proctor approval and the exam clock keeps running (Handbook, pp. 5, 8, 10).
- Commit to each answer. Once you submit an answer, you can't go back to that question or change it (DANB). Read each question fully and pick the best practice; DANB says questions aren't designed to trick you and that most candidates finish with time remaining (DANB: 4 important details to know about DANB exams).
If you don't pass one exam
There's no limit on retakes. You reapply and pay the full fee for that exam, and the exams you passed still count as long as all three are passed within five years. Some states require extra education after failed attempts. If you think there was a scoring error, you can request hand scoring within 7 calendar days after results post (Handbook, pp. 4 and 14).
Quick answers
Who can take GC or the full CDA? For 2026 there are three pathways, and each also needs a current hands-on CPR, BLS or ACLS card: Pathway I, graduating from a CODA-accredited dental assisting or dental hygiene program (or holding an RDH license from any state except Alabama); Pathway II, at least 3,500 hours of dental assisting work over 2 to 4 years, verified by a licensed dentist, plus a high school diploma or equivalent; Pathway III, a former CDA, a DDS/DMD student or graduate, a dental graduate from outside the U.S. or Canada, or a DANB-accepted post-baccalaureate program (Application Packet, pp. 3–4).
Is a new pathway coming? Yes. On Sept. 23, 2026, DANB announced a new CDA pathway for graduates of DANB-approved dental assisting programs that aren't CODA-accredited but are in schools accredited by a U.S. Department of Education–approved agency. DANB says it will be officially available in early 2027. It isn't part of the 2026 application, and DANB says it doesn't change the standard candidates must meet to earn the CDA.
Does the CDA let me take x-rays or do expanded duties? Only where your state recognizes it. DANB states that passing its exams or earning certification conveys authority to perform duties only in states that accept those exams or that certification. Look up your state on DANB's state requirements page and confirm with your state dental board.
Can I test in Spanish? DANB's 2026 packet offers RHS, ICE and the combined RHS/ICE exam in Spanish (p. 14). GC isn't listed.
How do I keep the CDA after I earn it? Renew every year: earn the required continuing dental education credits, answer DANB's background questions, keep a DANB-accepted hands-on CPR, BLS or ACLS card, and pay the renewal fee (Handbook, p. 15).
Sources
Last verified: October 23, 2026. We checked the DANB exam facts, fees, policies and outlines on this page against the documents below on that date, and checked each practice question against the source linked beneath it.
DANB
- Certified Dental Assistant exam page
- 2026 CDA Application Packet (updated May 13, 2026)
- 2026 Candidate Handbook (updated June 22, 2026)
- GC Exam Outline and References (effective July 1, 2022)
- RHS Exam Outline and References (effective March 12, 2025)
- ICE Exam Outline and References (effective March 12, 2025)
- Prepare for Exams and Study Guides
- DANB introduces new CDA certification pathway (Sept. 23, 2026)
- 4 important details to know about DANB exams and Clearing up 5 common misconceptions about DANB exams
- State requirements
Teaching sources for the practice questions
- CDC, Guidelines for Infection Control in Dental Health-Care Settings — 2003; Sterilization Monitoring; Dental Unit Water Quality
- American Dental Association, updated radiography safety recommendations (Feb. 1, 2024)
- DE 115: Dental Radiography, ch. 22.1; Digital Radiographic Exposure, ch. 8
- National Research Council, Radiation Quantities and Units, Definitions (1999)
- American Dental Association, Universal Tooth Designation System value set (July 2024)
- NIDDK, Low Blood Glucose (Hypoglycemia)
- HHS, HIPAA Minimum Necessary Requirement
- Dimensional stability of irreversible hydrocolloid impression materials as a function of pouring time: a systematic review, Journal of Prosthetic Dentistry, 2011
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