Orthodontic Dental Nursing · NEBDN certificate
Materials, Debonding and Retention
Impressions and study models, bonding and cementation, archwire properties, debonding hazards, retainers.
What the appliances are made of, and what happens once they come off. The topic covers impression materials and taking impressions, study models and orthodontic records, bonding and cementation materials, and the properties that make one archwire material behave differently from another. It then covers debonding and its specific hazards, and retention — retainer types, their indications and how retention is managed — together with cross-infection control and instrument care. Extended matching questions run through all of it, pairing materials, instruments and retainers with the job they are for.
What this topic covers
These are the sub-topics the app's 60 questions for this topic are grouped into, with the number of questions on each. They are a fair map of where the weight sits.
| Sub-topic | Questions |
|---|---|
| EMQ: Instruments and the procedures they serve | 8 |
| EMQ: Orthodontic materials and their use | 8 |
| EMQ: Retainers and their indications | 8 |
| Impression materials and taking impressions | 7 |
| Bonding and cementation materials | 6 |
| Retention and retainer types | 6 |
| Archwire materials and their properties | 5 |
| Debonding and its hazards | 5 |
| Study models and orthodontic records | 4 |
| Cross-infection control and instrument care | 3 |
Sub-topics beginning “EMQ” are extended matching questions: one stem, one right answer, and a list of up to 9 options to choose it from. They are testing whether you can discriminate between neighbouring answers, not whether you recognise the right one.
Study guide
What appliances are made of, how records are taken, and what happens when treatment ends. Retention carries real weight here, and rightly so: it is the stage at which the result is either held or lost, and the assessment gives it its own extended matching set.
Impressions and study models
Records first, because everything downstream depends on them.
- Impression materials have different handling characteristics and different indications; questions match material to use.
- Technique faults in an impression have recognisable consequences for the model.
- Study models and other orthodontic records serve defined purposes at defined stages of treatment.
Bonding, cementation and archwire materials
The materials that hold the appliance on and the materials that move the teeth.
- Bonding and cementation materials differ in how they set and what they are used for — the distinction is examined.
- Archwire materials have different properties, and the property is the reason the wire is chosen.
- An extended matching set covers orthodontic materials and their uses across this whole block.
Debonding and its hazards
A short block with specific safety content.
- Debonding has defined hazards for both patient and operator, and protective measures follow from them.
- Removing residual adhesive is part of the procedure, with its own considerations for the enamel surface.
- Instruments used at debond appear in the instruments extended matching set.
Retention and retainers
Where the result is kept, and a large examinable block.
- Retention is necessary because teeth tend to relapse — the reason is examinable, not just the practice.
- Retainer types differ in whether the patient can remove them, and each has its own indications.
- An extended matching set pairs retainers with their indications; learn which patient gets which and why.
Instruments and cross-infection control
The practical background running through the whole certificate.
- Instruments are matched to the procedures they serve in their own extended matching set.
- Instrument care and cross-infection control apply to orthodontic instruments as to any others, with some items needing particular handling.
In the exam Retention and the two instrument/material matching sets are where the marks concentrate. Learn materials by property rather than by name — the questions describe what is needed and expect you to name what has that property, so a list of names without properties attached will not answer them.
This topic's questions are in the app
The free tier does not unlock any of the 60 questions for this topic, so there is no quiz to run here — and publishing one anyway would give away more than the app itself does. The study guide above is free to read in full.
To practise this topic, get the app. Or start with one of the topics that are free here .
For iPhone, iPad and Android.
Carry on with
Growth and Classification
Malocclusion and occlusal classification, eruption and the developing dentition, indices, cephalometrics.
Removable and Fixed Appliances
Removable and fixed components, functional appliances, headgear, auxiliaries, and chairside problems.
Physics and Dose
X-ray production, dose quantities and limits, biological effects, justification and optimisation.
Revise anywhere, with the whole Radiography & Post-Reg bank
This site publishes the app's free sample — 48 of 780 questions, across 4 of 17 topics. Dental Radiography & Post-Reg carries the full bank offline across all 4 certificates, so you can revise on the bus, between patients, or the night before.
- All 780 questions
- Every question across all 4 certificates, including the 13 topics this site cannot unlock.
- 75-question mock test
- Timed at 90 minutes, drawn from one certificate at a time.
- An explanation every time
- Every answer explains itself and cites where it comes from, right or wrong.
- Progress you can see
- History and per-topic results show which certificates still need the work.
For iPhone, iPad and Android.
