What is a cavity, and how is it treated?
A cavity (dental caries) forms when bacteria in plaque turn sugars into acid, which slowly dissolves the hard enamel. Once decay passes through enamel into the softer dentin beneath, it spreads faster and the tooth will not repair itself. Treatment means removing the infected tooth structure and sealing the space with a durable restoration.
How we treat a cavity depends on how far it has progressed:
- Early enamel lesions(white chalky spots): may be managed with fluoride, better brushing and diet changes, then monitored.
- Small to moderate cavities: usually restored with tooth-colored composite fillings.
- Larger cavities on back teeth: often better served by inlays or onlays, which are made to fit and resist chewing forces.
- Decay close to or into the nerve: may require root canal treatment followed by a crown.
Signs you may have a cavity
Many cavities cause no pain until they are deep, which is why regular examinations matter. Possible signs include:
- A brief twinge with sweet, hot or cold food
- Food repeatedly catching between two teeth
- A dark spot, rough area or visible hole
- Pain when biting down
Some of these symptoms overlap with exposed roots or enamel wear; our page on tooth sensitivity covers those causes.
Who needs cavity treatment?
Anyone with active decay should have it assessed. Patients who are at higher risk include those with a dry mouth (often a side effect of medication), people with many existing fillings, adults with receding gums and exposed roots, and children with newly erupted teeth. Older adults and patients with chronic conditions also benefit from closer monitoring, since decay can progress quietly around old crowns. For young patients, see our page on baby teeth cavity care.
Not every dark mark needs drilling. Stained grooves can be harmless, and a small enamel lesion may be stopped without a filling. We will show you what we see and explain whether treatment is needed now or whether monitoring is reasonable.
How cavity treatment works at E&D Dental
- Detection. We examine each tooth and use the Q-ray intraoral camera, which highlights plaque biofilm, early decay and cracks so you can see them on screen. X-rays check between teeth and how close decay is to the nerve.
- Comfortable numbing. Small enamel fillings sometimes need no anesthetic. When they do, our 3-step painless anesthesia system begins with a topical gel or gargle, followed by Endo-Frost cold numbing and a computer-controlled injection.
- Removing decay. Only the softened, infected tooth structure is removed, preserving as much healthy tooth as possible.
- Restoring the tooth. Composite resin is bonded in layers and shaped to your bite in one visit, or an impression is taken so an inlay, onlay or crown can be made to fit, with a temporary restoration protecting the tooth in between.
- Bite check and polish. We adjust the restoration so your bite feels natural and polish it smooth to resist new plaque.
Aftercare
- If you were numbed, wait until feeling returns before eating to avoid biting your cheek.
- Mild sensitivity to cold for a short period after a deeper filling is common.
- Contact us if the bite feels high, or if pain lingers or worsens over several days.
- Brush twice daily with fluoride toothpaste, clean between teeth, and limit frequent sugary snacks and drinks.
Risks and limitations
Fillings do not last forever and can wear, chip or develop new decay at their edges. In a deep cavity, the nerve may already be irritated; occasionally it does not recover and a root canal becomes necessary later. Large fillings in back teeth can leave remaining walls weak, which is why we sometimes recommend an onlay or crown rather than a bigger filling.
Why patients in Sanbon and Gunpo choose E&D Dental for cavities
- See it yourself: Q-ray images help explain clearly why treatment is or is not needed.
- Conservative approach: we remove only what is necessary to protect your natural tooth.
- Comfort-focused care: a three-stage anesthesia approach designed to minimize discomfort for anxious patients.
- Prevention after treatment: regular check-ups and professional cleaning help stop new decay.
- Accessible hours: evening slots on Monday and Thursday and Saturday mornings, near Sanbon Station on Line 4.
International residents can ask about English communication when booking. See what happens at your first visit or book a cavity check at our Sanbon clinic.