Overseas Registration Exam (ORE) Paediatric Dentistry and Orthodontics Syllabus

What is apexogenesis in an immature permanent tooth?

A vital pulp therapy aiming to preserve the vital radicular pulp so that normal root development and physiological apical closure continue.

What is apexification, and what materials are used?

Inducing a calcified apical barrier (or placing an artificial one) in a non-vital immature permanent tooth to allow root canal filling. Traditionally calcium hydroxide over months; now commonly an MTA apical plug in a single visit.

What is regenerative endodontics (revascularisation) in an immature non-vital permanent tooth?

A procedure that disinfects the canal, induces a blood clot/scaffold from the periapical tissues, and seals with MTA to allow continued root development (thickening of walls and apical closure) by stem-cell-mediated tissue ingrowth.

Why is MTA favoured for vital pulp therapy in immature permanent teeth?

It provides a good biological seal, is biocompatible, promotes hard-tissue (dentine bridge) formation, and sets in the presence of moisture/blood.

What fluoride concentration toothpaste is recommended for children aged 0-3 years at standard caries risk in the UK?

A toothpaste containing at least 1000 ppm fluoride, using only a smear amount, twice daily.

What amount and fluoride concentration of toothpaste is advised for children aged 3-6 years?

A pea-sized amount of toothpaste containing more than 1000 ppm fluoride, twice daily, spitting out and not rinsing.

For children aged 7 and over (and adults), what fluoride toothpaste concentration is recommended?

1350-1500 ppm fluoride, brushing twice daily, last thing at night and on one other occasion.

At what concentration and frequency is fluoride varnish applied for caries prevention in children?

$22{,}600$ ppm fluoride (2.26% NaF, e.g. Duraphat) applied twice yearly; up to four times yearly for children at higher caries risk (from age 2 upward, or from tooth eruption in high-risk cases).

Name the main mechanisms by which fluoride prevents dental caries.

Promotes remineralisation and inhibits demineralisation of enamel, forms more acid-resistant fluorapatite, and inhibits bacterial metabolism/acid production. Its predominant effect is topical and post-eruptive.

When are fluoride supplements (drops/tablets) considered, per UK guidance?

Only for children at high caries risk where the water supply is non-fluoridated, after assessing total fluoride intake; they are not routinely recommended due to fluorosis risk and poor compliance.

What is the prime indication for placing fissure sealants and which material is most commonly used?

Caries prevention in deep, retentive pits and fissures of permanent molars (especially in higher-risk children); resin-based sealants are most commonly used, with glass ionomer as an alternative where moisture control is difficult.

Summarise the key dietary advice for caries prevention in children.

Limit the amount and frequency of sugar (free sugars) intake, restrict sugary foods/drinks to mealtimes, avoid sugary snacks and drinks between meals and at bedtime, and choose water or plain milk as safe drinks.

What document provides the UK's evidence-based prevention guidance for dental teams?

'Delivering Better Oral Health: an evidence-based toolkit for prevention' (DBOH), published by Public Health England/OHID.

According to DBOH, what brushing supervision advice should be given for young children?

Children should brush or be assisted in brushing twice daily with fluoride toothpaste, and brushing should be supervised by an adult until at least 7 years of age.

What is Molar Incisor Hypomineralisation (MIH)?

A developmental qualitative enamel defect of systemic origin affecting one or more first permanent molars, frequently with incisor involvement, producing demarcated opacities (white/cream to yellow/brown) that may show post-eruptive enamel breakdown and sensitivity.

How does amelogenesis imperfecta differ from MIH in distribution?

Amelogenesis imperfecta is a hereditary defect affecting essentially all teeth in both dentitions generally, whereas MIH is acquired and affects specific teeth (first permanent molars and incisors).

Name the three main types of amelogenesis imperfecta.

Hypoplastic (reduced enamel quantity, thin/pitted), hypomineralised/hypocalcified (soft, easily lost enamel), and hypomaturation (normal thickness but mottled, weaker enamel).

What is dentinogenesis imperfecta and its classic clinical appearance?

A hereditary defect of dentine giving teeth an opalescent grey-brown/blue discolouration, with enamel that chips away leading to rapid attrition; radiographs show bulbous crowns and obliterated pulp chambers. Type I is associated with osteogenesis imperfecta.

Define hypodontia and oligodontia.

Hypodontia is the developmental absence of one or more teeth (excluding third molars). Oligodontia is the absence of six or more teeth (excluding third molars). Anodontia is the complete absence of teeth.

Which teeth are most commonly congenitally absent (excluding third molars)?

Mandibular second premolars, followed by maxillary lateral incisors, then maxillary second premolars.

What is a supernumerary tooth and name the common types.

A tooth additional to the normal complement. Types: conical (peg-shaped, e.g. mesiodens), tuberculate, supplemental (normal morphology, e.g. extra lateral incisor), and odontome.

What is a mesiodens and its main clinical consequence?

A conical supernumerary tooth located in the maxillary midline; it commonly causes failure of eruption or displacement of the permanent central incisors.

What is the recommended first-aid for an avulsed permanent tooth at the scene?

Find the tooth, hold by the crown (not root), rinse gently if dirty, reimplant immediately into the socket and bite on a cloth; if not possible, store in milk, saliva or saline (not water) and seek urgent dental care.

Why should an avulsed primary tooth NOT be reimplanted?

Reimplantation risks damage to the developing permanent successor tooth germ and ankylosis/infection, so avulsed primary teeth are not replanted.

Define the difference between subluxation, luxation and avulsion.

Subluxation: tooth loosened but not displaced. Luxation: tooth displaced (lateral, intrusive or extrusive) within/from the socket. Avulsion: complete displacement of the tooth out of its socket.

What classification describes crown/root fractures of teeth following trauma?

Ellis classification (and WHO/Andreasen): enamel fracture, enamel-dentine fracture, enamel-dentine-pulp (complicated) fracture, crown-root fracture, root fracture, and alveolar fracture.

In Angle's classification of malocclusion, what defines Class I, II and III?

Based on the mesiobuccal cusp of the upper first molar relative to the buccal groove of the lower first molar: Class I = normal relationship; Class II = lower molar distal (upper anterior); Class III = lower molar mesial (upper posterior).

What is the difference between Angle Class II division 1 and division 2?

Class II div 1: upper central incisors proclined with increased overjet. Class II div 2: upper central incisors retroclined (often with deep overbite and increased interincisal angle).

Define overjet and overbite.

Overjet is the horizontal distance between the upper and lower incisor edges (normal ~2-4 mm). Overbite is the vertical overlap of the lower incisors by the upper incisors (normally upper covers about one third of lower crowns).

What is the IOTN and what are its two components?

The Index of Orthodontic Treatment Need, used to assess need for treatment. It has a Dental Health Component (grades 1-5, 4-5 indicating need) and an Aesthetic Component (10-point photographic scale).

Give examples of local, environmental and skeletal aetiological factors of malocclusion.

Local: supernumerary/missing teeth, crowding, ectopic eruption, digit sucking. Environmental/soft-tissue: habits, lip/tongue posture. Skeletal: anteroposterior, vertical and transverse jaw discrepancies. Genetic/hereditary factors underlie much skeletal pattern.

What is interceptive orthodontics and give an example.

Treatment carried out in the mixed dentition to eliminate or reduce the severity of a developing malocclusion. Examples: extraction of retained primary teeth, removal of supernumeraries, or use of space maintainers after early tooth loss.

What is a space maintainer and when is it indicated?

An appliance (e.g. band-and-loop, lingual arch) used to preserve the space of a prematurely lost primary tooth, preventing adjacent teeth drifting and loss of arch length before the permanent successor erupts.

What is the difference between a removable and a fixed orthodontic appliance?

Removable appliances can be taken out by the patient and typically tip teeth, used for simple movements/growth modification. Fixed appliances (brackets and archwires) are bonded and allow precise three-dimensional bodily movement of teeth.

What is a functional appliance and what does it treat?

A (usually removable) appliance that uses the forces of the orofacial muscles, generated by posturing the mandible forward, to modify growth and correct Class II malocclusion in growing children (e.g. Twin Block, Frankel).

What is the typical referral indication for an unerupted/ectopic maxillary canine, and when should it be assessed?

Palpate for the canine bulge from about age 9-10; if not palpable by ~10-11 years, radiographic localisation and specialist orthodontic referral are indicated, as interceptive extraction of the primary canine may aid eruption.

What is serial extraction in orthodontics?

A planned sequence of extractions (primary canines, then first primary molars, then first premolars) in severe crowding cases to guide erupting permanent teeth into better alignment; used selectively and under specialist guidance.

What is a 'balancing' versus 'compensating' extraction in paediatric dentistry?

A balancing extraction is removal of the contralateral tooth in the same arch to prevent centreline shift. A compensating extraction is removal of the equivalent tooth in the opposing arch to maintain occlusal relationships.