Free GDC Overseas Registration Examination Part 1 Practice Questions

Sample Practice Questions

Try these 10 sample questions from the GDC Overseas Registration Examination Part 1 practice bank. Each includes the answer and explanation. Continue with the interactive practice above to review the full question set.

1. 1A patient is generally comfortable attending the dentist but becomes markedly anxious immediately before a local anaesthetic injection. Which concept best describes the anxiety at that moment?

   1. A.Trait anxiety
   2. B.State anxietyCorrect answer: B
   3. C.Generalised anxiety disorder
   4. D.Dental phobia

   Explanation: The source states: "the individual’s degree of concern at a specific point in time" The anxiety described is a transient response at a particular moment. Trait anxiety is an enduring disposition; the vignette does not establish persistent generalised anxiety or a dental phobia.

   Reference: NHS England: Clinical standards for dental anxiety management — Section 2.1

2. 2What is a principal reason for using rubber dam during root canal treatment?

   1. A.It determines the apical working length mechanically
   2. B.It disinfects the root canals without irrigation
   3. C.It isolates saliva and protects the mouth from debrisCorrect answer: C
   4. D.It substitutes for the definitive coronal restoration

   Explanation: The source states: "to protect the tooth from saliva, and protect your mouth from debris" Rubber dam isolates the tooth and protects the mouth. It does not measure working length, disinfect canals instead of irrigation or replace restoration.

   Reference: University of Bristol Dental School: Root Canal Treatment — Treatment, During your Root canal treatment

3. 3During treatment, an anxious patient and dentist agree that a raised hand means treatment will pause. What is the principal behavioural purpose of this arrangement?

   1. A.Increasing the patient's perceived controlCorrect answer: A
   2. B.Testing the patient's pain threshold
   3. C.Reinforcing avoidance of future visits
   4. D.Measuring the patient's trait anxiety

   Explanation: NHS England states: "The use of STOP signal is simple, yet so effective" An agreed stop signal gives the patient a way to influence treatment and increases perceived control. It is not a pain-threshold test, an anxiety-scale measurement, or reinforcement of long-term avoidance.

   Reference: NHS England: Clinical standards for dental anxiety management — Appendix 1, Enhancing control

4. 4An immunocompetent adult has a localised acute apical abscess. Drainage can be achieved immediately; there is no spreading infection or systemic illness. Which approach addresses the cause most appropriately?

   1. A.Provide local drainage and definitive treatment of the causative toothCorrect answer: A
   2. B.Prescribe repeated antibiotics without treating the tooth
   3. C.Delay all local treatment until an antibiotic course is completed
   4. D.Use analgesics alone as the definitive treatment

   Explanation: The source states: "Treat dental abscesses in the first instance using local measures to achieve drainage, with removal of the cause if possible." For the stated localised, drainable infection without systemic involvement, local treatment addresses the source. Antibiotics do not replace source control; delaying drainage or giving analgesics alone does not treat the causative infection.

   Reference: SDCEP: Drug Prescribing for Dentistry—Dental abscess — Dental abscess, initial management

5. 5A patient tends to faint at the sight of an injection. Which physiological effect explains the use of applied tension for this problem?

   1. A.Reducing heart rate to limit oxygen demand
   2. B.Producing amnesia for the injection
   3. C.Reducing the vasovagal fall in blood pressureCorrect answer: C
   4. D.Blocking nociceptive nerve conduction

   Explanation: NHS England states: "reducing the fall in blood pressure associated with the vaso-vagal response" Applied tension counters the fainting mechanism by limiting the blood-pressure fall. The alternatives confuse it with slowing the heart, a sedative effect, or local anaesthesia.

   Reference: NHS England: Clinical standards for dental anxiety management — Appendix 1, Managing physiological arousal

6. 6Soon after dental trauma, a tooth gives no response to a cold sensibility test. What is the most appropriate interpretation of that result alone?

   1. A.The test alone establishes a root fracture
   2. B.The test alone establishes pulp necrosis
   3. C.The test demonstrates a normal vital pulp response
   4. D.A false negative remains possible after recent traumaCorrect answer: D

   Explanation: The source states: "Be wary of false negative pulp tests particularly in older patients, heavily restored teeth and teeth that have experienced recent trauma" Recent trauma can cause a false-negative sensibility result. The negative result is not a demonstrated normal response and alone establishes neither necrosis nor a root fracture.

   Reference: British Endodontic Society: A Guide to Good Endodontic Practice — Chapter 1, Pulp testing, Key points

7. 7Which description best captures the basis of cognitive behavioural therapy for dental phobia?

   1. A.Using repeated sedation to suppress recall of dental visits
   2. B.Working on unhelpful thoughts and associated behavioursCorrect answer: B
   3. C.Replacing exposure to dentistry with permanent avoidance
   4. D.Interpreting unconscious conflicts without behavioural work

   Explanation: NHS England states: "new strategies to solve problems related to their thoughts and behaviour" CBT addresses cognition and behaviour together. Sedation alone, reinforcing avoidance and an exclusively unconscious-conflict approach do not describe that mechanism.

   Reference: NHS England: Clinical standards for dental anxiety management — Appendix 2, Cognitive Behavioural Therapy

8. 8Sodium hypochlorite is inadvertently extruded beyond a root apex during irrigation. Which complication can result directly from this event?

   1. A.Chemical injury to the surrounding vital tissuesCorrect answer: A
   2. B.Latex allergy caused by the rubber dam
   3. C.Mechanical injury from a fractured instrument
   4. D.Occlusal trauma caused by a high restoration

   Explanation: The source states: "can spill out into the vital tissues surrounding the tip of the tooth's root and cause injury" Extruded hypochlorite can chemically injure periapical tissues. Latex allergy, instrument injury and a high restoration involve different causes.

   Reference: University of Bristol Dental School: Root Canal Treatment — Risks of treatment, Extrusion of hypochlorite

9. 9An anxious patient has several non-urgent treatments planned and prefers a gradual approach. What does treatment staging involve?

   1. A.Completing all invasive procedures before familiarisation
   2. B.Repeating assessment visits without progressing treatment
   3. C.Using identical appointment content regardless of response
   4. D.Progressing from less invasive to more invasive treatmentCorrect answer: D

   Explanation: NHS England states: "from those perceived as less invasive by the patient to those that are more invasive" For this patient, staged progression builds support and confidence over visits. Starting with the most invasive care reverses the approach; indefinite assessment and identical content do not provide graded progression.

   Reference: NHS England: Clinical standards for dental anxiety management — Appendix 2, Treatment staging

10. 10A root-filled posterior tooth has substantial loss of coronal structure. Why is an appropriate definitive restoration important after endodontic treatment?

    1. A.It disinfects uninstrumented portions of the root canals
    2. B.It replaces the apical seal provided by the root filling
    3. C.It protects the weakened tooth and restores functionCorrect answer: C
    4. D.It re-establishes the removed pulp's normal blood supply

    Explanation: The source states: "restore a tooth with a filling or crown after root canal treatment to protect the weakened tooth" Definitive restoration protects weakened remaining structure and restores function. It does not replace intracanal disinfection or the apical filling, or restore removed pulpal blood supply.

    Reference: University of Bristol Dental School: Root Canal Treatment — What happens after root canal treatment?