ORE Part 2 Paediatric Dentistry 3 — Questions and Answers
Question 1: A child has an avulsed permanent upper central incisor (open apex). What is the maximum out-of-socket time for a favourable reimplantation prognosis?
- Less than 60 minutes, ideally under 15–20 minutes (Correct answer)
- Less than 24 hours
- Up to 2 hours
- Time out of socket is not relevant
Correct answer: Less than 60 minutes, ideally under 15–20 minutes
For optimal PDL cell viability, reimplantation should occur within 20–30 minutes (dry storage). After 60 minutes dry storage, PDL cells are non-viable, though reimplantation may still be attempted for bone preservation.
Question 2: What is the recommended management of a subluxed primary upper incisor with displacement towards the permanent tooth germ?
- Extraction of the primary tooth to protect the permanent successor (Correct answer)
- Repositioning and splinting
- Monitoring without intervention
- Root canal treatment of the primary tooth
Correct answer: Extraction of the primary tooth to protect the permanent successor
Intruded or severely displaced primary teeth can damage the developing permanent tooth germ; extraction is recommended when displacement threatens the permanent successor's development.
Question 3: Which interceptive orthodontic appliance is used to maintain space following premature loss of a primary first molar?
- Band and loop space maintainer (Correct answer)
- Removable retainer
- Functional appliance
- Transpalatal arch only
Correct answer: Band and loop space maintainer
A band and loop space maintainer (fixed) is used after premature primary molar loss to prevent mesial drift of the first permanent molar and preserve space for the permanent premolar.
Question 4: What is the recommended DMFT index for assessing dental caries experience in a child?
- DMFT counts decayed, missing (due to caries), and filled teeth in the permanent dentition (Correct answer)
- DMFT counts all missing teeth including trauma
- DMFT only records untreated decay
- DMFT is used for primary teeth only
Correct answer: DMFT counts decayed, missing (due to caries), and filled teeth in the permanent dentition
DMFT (Decayed, Missing, Filled Teeth) records the total caries experience in permanent teeth; dmft (lowercase) is used for primary teeth to distinguish between the two dentitions.
Question 5: What is the most common dental anomaly associated with Down's syndrome?
- Hypodontia (congenitally missing teeth), delayed eruption, and microdontia (Correct answer)
- Macrodontia
- Enamel hypoplasia only
- Early eruption of all teeth
Correct answer: Hypodontia (congenitally missing teeth), delayed eruption, and microdontia
Down's syndrome is associated with hypodontia, delayed and irregular eruption, microdontia, and high caries risk, requiring careful monitoring and preventive dental care.
Question 6: When is nitrous oxide/oxygen inhalation sedation appropriate for a child in UK dental practice?
- When local anaesthesia alone is insufficient and the child is moderately anxious but cooperative (Correct answer)
- As a replacement for local anaesthesia
- For all anxious children regardless of cooperation
- Only in hospital settings
Correct answer: When local anaesthesia alone is insufficient and the child is moderately anxious but cooperative
Relative analgesia with nitrous oxide/oxygen is indicated for cooperative but anxious children when behavioural management and LA alone are insufficient; it is safe for conscious sedation in general practice.
ORE Part 2 Paediatric Dentistry 3
A child has an avulsed permanent upper central incisor (open apex).
What is the maximum out-of-socket time for a favourable reimplantation prognosis?