Minimal intervention: when to drill and when not
- Topic
Not every cavity needs a filling. Early caries can be stopped without drilling, and when a filling is needed, as much healthy tooth as possible is kept.
What it is
Minimal intervention dentistry treats caries as a disease of the biofilm, not just a hole to fill. It has four steps: find the disease early and judge the patient's risk, stop and reverse early lesions without drilling, remove only the tissue that must go when a restoration is needed, and repair rather than replace old restorations. Every restoration starts a cycle of re-treatment, each one larger, so the best restoration is the one that is not needed yet.
Key facts
- A non-cavitated lesion (white spot, intact surface) can remineralise with fluoride, biofilm control and less sugar: it is monitored, not drilled.
- Sealants and resin infiltration can stop early lesions in pits and between teeth.
- Selective caries removal leaves soft, affected dentine over the pulp under a sealed restoration, to avoid exposing the pulp.
- The outer, infected dentine is removed; the inner, affected dentine can remineralise once sealed off from sugar.
- Atraumatic restorative treatment (ART) uses hand instruments and glass ionomer, without electricity or a drill, useful in the community and in children.
In clinical practice
- Drilling a lesion that could have arrested weakens the tooth for life and starts the restoration cycle.
- A restoration does not cure caries: without diet, hygiene and fluoride changes, new lesions appear at its margins.
- Repairing a defective margin keeps more tooth than replacing the whole filling and is often as durable.
Next step / Initial management
- Assess caries risk (diet, fluoride, saliva, past caries) and record lesions as active or inactive, cavitated or not.
- Non-cavitated lesions: fluoride varnish, sealant or infiltration, diet and hygiene advice, and review.
- Cavitated lesions, pain or deep lesions near the pulp: refer to the dentist for selective removal and a sealed restoration.
Test yourself
Think of the answer, then tap the question to see it.
What is done with a non-cavitated white-spot lesion in a low-risk patient?
It is monitored and arrested with fluoride, biofilm control and less sugar; it is not drilled.
Why is soft dentine sometimes left over the pulp in a deep cavity?
Selective removal avoids exposing the pulp; once sealed under a restoration the remaining affected dentine can harden and bacteria lose their sugar supply.
What does ART stand for and what material does it use?
Atraumatic restorative treatment: hand instruments and a glass ionomer cement, without a drill.
Connections
In Pharmacology1
Educational content; it does not replace assessment by a dentist or doctor and is not a clinical instruction. For facial or neck swelling with difficulty swallowing or breathing, a knocked-out tooth or bleeding that will not stop, go to an emergency department at once.
Sources: Minimally Invasive Therapies for the Management of Dental Caries: A Literature Review (Dentistry Journal (PMC open access), 2021); Guiding Caries Removal Through Biological Principles: A Narrative Review on Selective Caries Tissue Preservation (International Dental Journal (PMC open access), 2026); Dental Caries Diagnostic Testing (StatPearls Publishing (NCBI Bookshelf), 2023); Pit and Fissure Sealants (StatPearls Publishing (NCBI Bookshelf), 2025).
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Representative model, for educational purposes only.