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100+ Free NDAEB Theory Exam Practice Questions

Pass your NDAEB Theory Examination (National Dental Assisting Examining Board) exam on the first try — instant access, no signup required.

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2026 Statistics

Key Facts: NDAEB Theory Exam Exam

200 questions

Multiple-choice items on the NDAEB Theory Examination

NDAEB Theory Examination Candidate Handbook

4 hours

Time allowed to complete the Theory Exam

NDAEB Theory Examination Candidate Handbook

7 domains

Content areas defined in the NDAEB Domain Description

NDAEB Domain Description for Dental Assisting

40-50%

Patient Care Procedures is the largest exam domain

NDAEB Theory Examination Candidate Handbook

Low-to-mid 60s%

Typical passing-score range set by the modified Angoff method

NDAEB Theory Examination Candidate Handbook

$730 CAD

Theory Exam fee, including a $100 non-refundable application fee

NDAEB Theory Examination Candidate Handbook

FDI notation

The NDAEB identifies teeth using FDI Two-Digit numbering

NDAEB Theory Examination Candidate Handbook

100

Free original practice questions in this bank

OpenExamPrep

The NDAEB Theory Examination is Canada's national written certification exam for dental assistants, made up of 200 multiple-choice questions to be completed within 4 hours in English or French. It is built from the NDAEB Domain Description and covers seven domains, with Patient Care Procedures the largest at 40-50% and Preventive Procedures at 15-20%. There is no fixed pass mark; the modified Angoff method sets passing scores that generally land in the low-to-mid 60s percent range. The fee is $730 CAD (including a $100 non-refundable application fee). This 100-question bank provides original, weighting-aligned practice on chairside assisting, dental materials, infection control, radiography, anatomy and patient care; the separate Clinical Practice Evaluation is not included.

Sample NDAEB Theory Exam Practice Questions

Try these sample questions to test your NDAEB Theory Exam exam readiness. Each question includes a detailed explanation. Start the interactive quiz above for the full 100+ question experience with AI tutoring.

1During four-handed dentistry, the dental assistant transfers instruments in which zone relative to the patient's face on an imaginary clock?
A.The transfer zone, roughly 4 to 7 o'clock
B.The operator zone, roughly 7 to 12 o'clock
C.The static zone, roughly 12 to 2 o'clock
D.The assistant zone, roughly 2 to 4 o'clock
Explanation: In the clock concept of operating zones, instruments are passed in the transfer zone (about 4 to 7 o'clock for a right-handed operator), directly under the patient's chin and over the chest, so exchanges stay out of the patient's line of sight and away from sharps over the face.
2Which dental material is most appropriate as a base placed in a deep cavity preparation to protect the pulp from thermal shock under a metallic restoration?
A.Zinc phosphate or zinc oxide-eugenol base
B.Etchant gel
C.Pit-and-fissure sealant
D.Alginate
Explanation: A cement base such as zinc phosphate or zinc oxide-eugenol is placed in a thick layer in a deep preparation to provide thermal insulation, protecting the pulp from temperature changes transmitted through a metallic restoration.
3A patient in the dental chair becomes pale, sweaty and light-headed, then loses consciousness briefly. The most likely medical emergency is:
A.Syncope (fainting)
B.Myocardial infarction
C.Hyperventilation
D.Insulin overdose
Explanation: Syncope (vasovagal fainting) is the most common dental-office medical emergency. Warning signs include pallor, sweating and light-headedness followed by brief loss of consciousness. Management is to place the patient supine with legs slightly elevated to restore cerebral blood flow.
4When mixing dental amalgam, the process of combining the alloy and mercury in an amalgamator is called:
A.Trituration
B.Condensation
C.Carving
D.Burnishing
Explanation: Trituration is the mechanical mixing of the alloy powder and mercury in an amalgamator (capsule) to produce a homogeneous, workable amalgam mass before it is placed in the preparation.
5Three days after a tooth extraction, a patient reports severe throbbing pain radiating to the ear and a bad taste, with an empty-looking socket. This is most consistent with:
A.Alveolar osteitis (dry socket)
B.Normal post-operative healing
C.Acute pulpitis
D.Allergic reaction to anesthetic
Explanation: Alveolar osteitis, or dry socket, typically develops two to four days after extraction when the blood clot is lost or fails to form. It causes severe radiating pain, a foul odour/taste and an empty socket, and is managed by gentle irrigation and a medicated dressing.
6Which impression material is an irreversible hydrocolloid commonly used to take preliminary impressions for study models?
A.Alginate
B.Polyvinyl siloxane
C.Zinc oxide-eugenol paste
D.Gypsum
Explanation: Alginate is an irreversible hydrocolloid mixed from powder and water; once set it cannot return to a sol state. It is inexpensive and widely used for preliminary impressions for diagnostic study models and opposing arches.
7In endodontic treatment, the rubber dam is placed primarily to:
A.Isolate the tooth and prevent contamination and aspiration of instruments
B.Reduce the patient's blood pressure
C.Speed up local anesthesia
D.Replace the need for radiographs
Explanation: A rubber dam isolates the tooth during root canal therapy, keeping the field dry and free of saliva contamination, improving visibility, and preventing the patient from swallowing or aspirating small endodontic files and irrigants.
8Which of the following is a non-absorbable suture material?
A.Silk
B.Plain gut
C.Chromic gut
D.Polyglycolic acid
Explanation: Silk is a non-absorbable suture that must be removed by the clinician, typically 5 to 7 days after surgery. Absorbable sutures break down in tissue and do not require removal.
9After a tooth extraction, the dental assistant should instruct the patient to avoid which action during the first 24 hours to protect the blood clot?
A.Vigorous rinsing, spitting and using a straw
B.Keeping the head elevated when resting
C.Applying an ice pack to the cheek
D.Eating soft, cool foods
Explanation: Vigorous rinsing, spitting and drinking through a straw create suction and pressure changes that can dislodge the forming clot and lead to dry socket. Patients are told to avoid these actions for the first day.
10Light-cured composite resin hardens through which method of polymerization?
A.A visible blue light (around 450-470 nm) activates a photoinitiator
B.Mixing two pastes (base and catalyst)
C.Exposure to room air over several hours
D.Contact with the patient's saliva
Explanation: Light-cured composites contain a photoinitiator such as camphorquinone that is activated by visible blue light around 450-470 nm, starting polymerization on command. This gives the operator working time until the curing light is applied.

About the NDAEB Theory Exam Exam

The NDAEB Theory Examination is the national written certification exam for entry-to-practice intra-oral dental assistants in Canada. It is a computer-based, multiple-choice test of 200 questions completed within four hours, offered in English and French at test centres. Questions are built from the NDAEB Domain Description for Dental Assisting and span seven domains, with the largest share devoted to Patient Care Procedures (chairside assisting, dental materials and clinical support) and significant coverage of Preventive Procedures, Clinical Support Procedures (infection control and sterilization), Patient Records, Dental Sciences, professional conduct and practice management. The NDAEB uses FDI Two-Digit tooth notation. Passing scores are set using the modified Angoff standard-setting method and generally fall in the low-to-mid 60s percent range. The Theory Examination is one part of the NDAEB certificate; the separate hands-on Clinical Practice Evaluation (CPE) is assessed independently and is not covered by this question bank.

Assessment

200 single-best-answer multiple-choice questions across seven domains: Conduct in a Professional Setting (5-10%), Dental Sciences (7-12%), Clinical Support Procedures (10-15%), Patient Records (10-12%), Patient Care Procedures (40-50%), Practice Management Procedures (5-10%) and Preventive Procedures (15-20%).

Time Limit

4 hours (240 minutes), unless an approved accommodation grants additional time.

Passing Score

No fixed cutoff. Passing scores are set with the modified Angoff method and generally fall in the low-to-mid 60s percent range, varying with each form's difficulty.

Exam Fee

$730 CAD for both initial and rewrite attempts (includes a $100 non-refundable application fee); non-refundable after the exam. (National Dental Assisting Examining Board (NDAEB), via a contracted third-party testing provider)

NDAEB Theory Exam Exam Content Outline

40-50%

Patient Care Procedures

Largest domain. Chairside assisting and four/six-handed dentistry, dental materials (amalgam, composite, cements, bases and liners, impression materials, gypsum), restorative and prosthodontic support, oral surgery and suture care, endodontics, periodontics, orthodontics, local anesthesia and sedation support, and recognizing and managing medical emergencies in the dental office.

15-20%

Preventive Procedures

Coronal polishing technique and contraindications, topical fluoride and other anti-cariogenic agents, pit-and-fissure sealants, oral hygiene instruction, plaque and biofilm control, the caries process and diet/nutritional counselling related to oral health.

10-15%

Clinical Support Procedures

Asepsis and the chain of infection, Standard Precautions, surface barriers and disinfection, instrument processing from cleaning through sterilization and monitoring (biological/chemical indicators), waterline and equipment maintenance, and operatory turnover.

10-12%

Patient Records

Charting with FDI Two-Digit notation, gathering and updating medical/dental histories, recording vital signs, radiographic documentation, informed consent records and confidentiality of patient information.

7-12%

Dental Sciences

Tooth morphology and eruption, oral and dental anatomy and histology, head and neck anatomy and landmarks, microbiology, basic pharmacology and oral pathology relevant to assisting.

5-10%

Conduct Appropriate to a Professional Setting

Provincial/national codes of ethics, professional and legal responsibilities, scope of practice, confidentiality, patient-centred communication and interprofessional collaboration.

5-10%

Practice Management Procedures

Appointment scheduling and recall systems, inventory and supply control, dental insurance and billing terminology, WHMIS labels and pictograms, and general office safety and administration.

How to Pass the NDAEB Theory Exam Exam

What You Need to Know

  • Passing score: No fixed cutoff. Passing scores are set with the modified Angoff method and generally fall in the low-to-mid 60s percent range, varying with each form's difficulty.
  • Assessment: 200 single-best-answer multiple-choice questions across seven domains: Conduct in a Professional Setting (5-10%), Dental Sciences (7-12%), Clinical Support Procedures (10-15%), Patient Records (10-12%), Patient Care Procedures (40-50%), Practice Management Procedures (5-10%) and Preventive Procedures (15-20%).
  • Time limit: 4 hours (240 minutes), unless an approved accommodation grants additional time.
  • Exam fee: $730 CAD for both initial and rewrite attempts (includes a $100 non-refundable application fee); non-refundable after the exam.

Keys to Passing

  • Complete 500+ practice questions
  • Score 80%+ consistently before scheduling
  • Focus on highest-weighted sections
  • Use our AI tutor for tough concepts

NDAEB Theory Exam Study Tips from Top Performers

1Use the NDAEB Domain Description as your master checklist and confirm you can perform and explain every mandatory skill listed for each of the seven domains.
2Weight your study toward Patient Care Procedures (40-50%): master dental materials, chairside assisting sequences and medical-emergency management, since this domain carries the most questions.
3Learn FDI Two-Digit notation cold, because the NDAEB identifies teeth by quadrant and number (Q1-Q4) throughout the exam.
4Drill infection prevention and control to a reflex: chain of infection, sterilization methods, and biological/chemical monitoring all appear under Clinical Support Procedures.
5Study with a current reference such as Modern Dental Assisting (Bird and Robinson, 14th ed.) rather than course notes alone, as the NDAEB validates questions against listed textbooks.
6Practise timing: 200 questions in 240 minutes is about 72 seconds per item, so flag hard questions and return to them rather than stalling.

Frequently Asked Questions

How many questions are on the NDAEB Theory Examination and how long is it?

The Theory Exam has 200 multiple-choice questions and must be completed within 4 hours, unless extra time has been granted through an approved accommodation. It is offered in English and French.

What is the passing score for the NDAEB Theory Exam?

There is no fixed percentage cutoff. The NDAEB uses the modified Angoff standard-setting method; passing scores generally fall in the low-to-mid 60s percent range and vary with the difficulty of each test form.

What does the NDAEB Theory Exam cover?

It is based on the NDAEB Domain Description and covers seven domains: professional conduct, dental sciences, clinical support procedures, patient records, patient care procedures (the largest at 40-50%), practice management and preventive procedures.

Is the Clinical Practice Evaluation part of the Theory Exam?

No. The Clinical Practice Evaluation (CPE) is a separate hands-on skills assessment with its own fee and handbook. The Theory Examination is the written multiple-choice exam and is what this question bank covers.

How much does the NDAEB Theory Exam cost?

The Theory Exam fee is $730 CAD for initial or rewrite attempts, which includes a $100 non-refundable application fee. After the exam the fee is non-refundable whether you pass or fail.

Are these official NDAEB exam questions?

No. These are original OpenExamPrep practice questions modelled on the NDAEB Domain Description domains and weightings. The NDAEB does not publish its live exam items; use the Domain Description and a current dental assisting textbook for official study.