# Cavities and Fillings: From First Twinge to Fixed Tooth

A cavity is the most common chronic disease in both children and adults — and also one of the most preventable and most fixable. Here's the whole arc: how decay starts, what it feels like at each stage, what actually happens when we fill a tooth, and how to make this your last one.

## How a cavity forms

Decay is a slow chemical siege. Plaque bacteria eat the sugars and starches you eat, excrete acid, and the acid dissolves the mineral out of your enamel a little at a time. Saliva repairs some of the damage between attacks; when attacks outpace repair for months, the surface finally breaks and a cavity — a real hole — begins.

The stages, and what you'd notice:

1. **White spot.** A chalky, matte patch where mineral has been leached out. *Feels like: nothing.* This stage is still **reversible** with fluoride, cleaning, and diet changes — no drill required.
2. **Enamel cavity.** The surface breaks. A brown or dark spot may appear. *Feels like: usually still nothing.* Enamel has no nerves. This is why "it doesn't hurt" is not evidence of "it's fine."
3. **Dentin decay.** Past the enamel, decay reaches the softer dentin and speeds up dramatically. *Feels like: twinges with sweets, cold, or biting.* This is the classic filling stage.
4. **Pulp involvement.** Decay reaches the nerve at the tooth's center. *Feels like: real pain — lingering, throbbing, sometimes waking you at night.* Now the fix is a [root canal](root-canal-treatment.html), not a filling.
5. **Abscess.** Infection spreads past the root into bone and gum. *Feels like: severe pain, swelling, a bad taste, sometimes fever.* This is [an emergency](dental-emergencies.html).

The economics track the biology exactly: each stage costs several times the one before it. Catching decay at stages 1–2 is the entire financial argument for [checkups](dental-checkups.html) and X-rays.

## What getting a filling is actually like

For a routine cavity, the appointment usually runs 30–60 minutes:

1. **Numbing.** A topical gel first, then local anesthetic. The pinch lasts a few seconds; the numbness, a few hours. Nervous about this part? Say so — see [Dental Anxiety Is Real](dental-anxiety.html); we have options.
2. **Removing the decay.** The drill's job is precise: take out softened, infected tooth structure and nothing more. With numbing, you feel vibration and hear noise, not pain.
3. **Filling the space.** We place **composite resin** — a tooth-colored material bonded directly to the tooth — in thin layers, curing each with a blue light. Bonding lets us keep more healthy tooth than the old silver-filling era required, and the result blends in.
4. **Shaping and bite check.** We sculpt the anatomy back, have you tap on marking paper, and adjust until it feels like nothing at all. (If your bite still feels "tall" days later, come back — it's a two-minute fix, not a complaint.)

Afterward: eat once the numbness fades, expect possible mild temperature sensitivity for a few days to a couple of weeks, and then forget which tooth it was. A well-placed composite typically lasts on the order of 7–10+ years and can be replaced when it wears.

**When a filling isn't enough:** once decay or old fillings have consumed too much of the tooth, a filling has nothing to hold onto, and the tooth needs an onlay or crown for structural coverage. We'll show you on the photo or X-ray exactly why, so the recommendation never feels like a mystery.

## Making this your last cavity

A filling repairs damage; it doesn't change the conditions that caused it. The tooth next door is living in the same mouth. What actually moves your risk:

- Nail the daily basics — see [Brushing and Flossing, Done Properly](brushing-and-flossing.html).
- Fix the *frequency* of sugar and acid, not just the amount — see [How Food and Drink Shape Your Teeth](diet-and-your-teeth.html).
- Use fluoride like the repair supply it is — see [Fluoride, Explained](fluoride-explained.html).
- For kids' molars, [sealants](sealants-for-kids.html) close the grooves where most childhood cavities start.

## When to see a dentist

Ideally: before anything hurts, at a routine checkup where a cavity is a small find and a small fix. Urgently: sweet or cold sensitivity that lingers, a visible hole or dark spot, food catching in the same place, or any toothache that lasts more than a day — [book a visit](../contact.html). Pain that throbs, wakes you, or comes with swelling shouldn't wait for a convenient slot: call us.

## Sources

- [Dental Caries Management Clinical Practice Guidelines](https://www.ada.org/resources/research/science/evidence-based-dental-research/caries-management-clinical-practice-guidelines) — How caries lesions are classified and managed.
- [Evidence-based clinical practice guideline on restorative treatments for caries lesions (JADA)](https://jada.ada.org/article/S0002-8177(23)00258-1/fulltext) — When a lesion needs a restoration, and which material is indicated.
- [Evidence-Based Clinical Practice Guideline on Nonrestorative Treatments for Caries Lesions](https://www.ada.org/resources/research/science/evidence-based-dental-research/caries-management-clinical-practice-guidelines/evidence-based-clinical-practice-guideline-on-nonrestorative-treatments-for-caries-lesions) — Arresting decay without drilling, including silver diamine fluoride.
- [Dental Caries (Tooth Decay) Data & Statistics](https://www.nidcr.nih.gov/research/data-statistics/dental-caries) — How common decay is in US adults and children.
- [Tooth Decay](https://medlineplus.gov/toothdecay.html) — Plain-language description of the decay process and its symptoms.

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*Reviewed by **Dr. James Sloengaard, DMD** — Fresh Dental Solutions, Portland, OR. This article is general dental-health education, not a diagnosis. For advice about your own teeth, [book a visit](../contact.html) or call [(503) 555-FRESH](tel:5035553737).*