How to use these questions
These eight single-best-answer questions cover decisions that recur across operative dentistry: when to restore, how to preserve pulp tissue, how to manage bonding and contacts, and how to respond to a post-operative complaint. They are practice questions for the subject, not a claim about the format of any particular examination. If you are preparing for a named examination, check its official website for its current format and syllabus.
For each item, choose the best option and then read the explanation. Pay attention to why a tempting alternative is weaker: in clinical questions, the correct answer often depends on one detail such as whether a surface is cavitated, whether isolation is reliable, or when the symptom began.
1. Non-cavitated proximal caries
This first MySummaries question tests whether a radiographic lesion automatically requires a restoration.
A 22-year-old has a matte white enamel lesion on the distal surface of a premolar. A bitewing shows radiolucency confined to enamel. The surface is intact, and there is no pain. What is the most appropriate management?
An intact, non-cavitated enamel lesion can often be managed non-operatively with caries-risk control, fluoride exposure and monitoring. A radiographic change alone does not establish that a restoration is needed. Restoring immediately is the strongest distractor, but it removes sound tissue without evidence that the surface cannot be kept clean or the lesion controlled. Antibiotics do not treat caries.
An intact surface can be cleaned and exposed to fluoride; a cavitated surface that cannot be kept plaque-free presents a different decision. Record the clinical appearance and radiographic depth so that review can assess change rather than relying on memory. Avoid treating the radiograph as a diagnosis in isolation.
2. Deep caries in a vital tooth
This question tests how to reduce the risk of pulp exposure when a deep lesion is being restored.
A permanent molar has a deep carious lesion. The patient reports brief sensitivity to cold, with no spontaneous pain. The tooth is vital and has no apical changes. During caries removal, what is the preferred approach at the pulpal wall?
For a deep lesion in a vital tooth without signs of irreversible pulp disease, selective caries removal can avoid unnecessary pulp exposure. The peripheral margin must support a durable seal; the pulpal dentine need not be excavated to hard dentine at the cost of exposing the pulp. Complete excavation to hard dentine is the strongest distractor because it sounds thorough, but it can increase exposure risk.
The key distinction is between the peripheral seal and the deepest pulpal area. A restoration that does not seal the lesion is not a substitute for sound caries management. Base the diagnosis on the history, clinical examination and appropriate tests; if the symptoms or findings suggest more advanced pulpal disease, the treatment decision changes.
3. Improving enamel bonding
This item tests a bonding step that can improve enamel adhesion when a universal adhesive is used.
You are placing a composite restoration with a universal adhesive. The preparation includes sound enamel margins. Which technique specifically improves bonding to those enamel margins?
Selective enamel etching with phosphoric acid before applying a universal adhesive can improve enamel bonding. Follow the adhesive manufacturer's instructions for application and curing. Extending acid exposure on dentine is the strongest distractor: it does not improve the enamel step and can make dentine bonding more technique-sensitive.
Keep the sequence clear: selective enamel etch, rinse, manage moisture as required by the adhesive, then apply and cure the adhesive as directed. Do not assume every universal adhesive has identical instructions or that a single timing rule applies to all products.
4. Proximal contact in a Class II composite
This question tests how to establish a tight proximal contact when restoring a posterior tooth.
A premolar requires a Class II composite restoration. The adjacent tooth is present, and a good proximal contact is required. Which setup is most appropriate?
A sectional matrix with a wedge and separation ring can help create and seal the proximal contour and contact for a posterior composite. A loose circumferential matrix is the strongest distractor because it provides a matrix, but without suitable adaptation and separation it may produce a flat or open contact. The matrix must be adapted to the preparation and checked before placing composite.
A wedge helps adapt the matrix at the gingival margin; the separation ring helps compensate for the matrix thickness and create contact. Check the cervical seal and matrix stability before bonding and filling. A correctly placed matrix is easier to manage than trying to repair an open contact after curing.
5. Polymerisation stress and cavity configuration
This item tests the cavity configuration factor and its relationship to bonded surfaces.
Which cavity configuration has the highest configuration factor (C-factor), meaning the greatest ratio of bonded to unbonded surfaces?
A Class I cavity has multiple bonded walls and a relatively small unbonded surface, so it has a high C-factor. A broad flat surface is the strongest distractor if the candidate focuses on restoration size, but it has a large free surface relative to bonded area. C-factor describes surface configuration, not simply the volume of composite.
The concept helps explain why bonded restorations can develop stress during polymerisation, but it does not replace sound material selection, incremental placement where indicated, or adequate curing. Think in terms of the proportion of bonded cavity walls to free surface, rather than assuming that the largest restoration always has the highest C-factor.
6. A root-surface lesion with difficult isolation
This question tests material selection where moisture control is less predictable and the restoration is on a root surface.
A patient with high caries risk has a small cervical root-surface lesion. The area is accessible but difficult to keep completely dry. Which restorative material is a reasonable choice?
Conventional glass-ionomer cement can be a reasonable choice for an accessible root-surface lesion when moisture control is difficult. It chemically bonds to tooth structure and releases fluoride, although it still requires careful placement and protection during setting. Composite without reliable isolation is the strongest distractor because it is often used for restorations, but contamination can compromise bonding.
Material choice is not a shortcut around diagnosis or isolation. Consider lesion location, occlusal loading, aesthetics, moisture control and the patient's caries risk. Follow the selected material's handling instructions, including any requirements to protect it during setting.
7. Delivering light to a composite restoration
This item tests a practical correction when the curing light is too far from the restoration.
While curing a posterior composite, you notice that the light guide has been held several millimetres away from the restoration and at an angle. What is the best correction for the next exposure?
A close, perpendicular light guide improves delivery of light to the restoration. Use the exposure specified for the material and curing unit, and check that the unit is functioning appropriately. Simply doubling the time is the strongest distractor: it does not correct poor positioning and is not a universal substitute for following the manufacturer's guidance.
Curing depends on more than the number displayed on a light unit. Keep the guide clean, position it consistently and account for access, restoration thickness and the material's instructions. If access prevents ideal positioning, reassess the curing approach rather than assuming the same exposure will always be sufficient.
8. Pain on biting after a new restoration
This final question tests how the timing and character of a symptom guide a post-operative check.
A patient returns the day after a posterior composite restoration. Cold sensitivity is brief, but the tooth feels sore when the patient bites. There is no spontaneous pain. What should you check first?
A premature occlusal contact is an important first check when biting discomfort starts soon after a restoration. Examine the occlusion and adjust a high contact if present, then reassess. Immediate root canal treatment is the strongest distractor because post-operative pain can raise concern about the pulp, but brief cold sensitivity and biting soreness alone do not establish irreversible pulp disease.
A sensible review starts with the complaint's onset and triggers, followed by examination and appropriate tests. Do not assume every symptom after a restoration means the pulp is irreversibly inflamed. If symptoms persist, worsen or change, reassess the diagnosis rather than repeatedly adjusting the restoration without further examination.
Where marks go missing
A useful review separates knowledge gaps from errors in applying a known principle. These example results show how a candidate might prioritise revision after a set of questions.
Start with the weakest section, then answer fresh questions on it. If you know the principle but miss a question because you overlook a detail in the stem, practise identifying that detail before choosing a material or procedure.
A repeated error can become a short retrieval prompt rather than a note to reread. This example targets the distinction between excavation at the margins and near the pulp.
You lost this mark twice: in a deep carious lesion in a vital tooth, where do you aim for hard dentine, and where can selective caries removal reduce pulp-exposure risk?
How MySummaries helps
MySummaries can turn your own operative dentistry notes into a revision board, then generate practice questions and cards from that material. Use the board to keep protocols and decision points together, and revisit the topics where your answers lose marks. Open MySummaries.