Stages of Dental Caries

A cavity is a journey from the outer enamel to the living nerve. Each stage has its own signs, its own treatment, and its own price - in money and in pain.

Stage 1: The white spot (reversible)

• Acid has begun dissolving enamel mineral, leaving a chalky white (or brown) patch
• No hole, no pain - and this stage can genuinely heal: fluoride, less sugar frequency and better brushing let saliva re-mineralise the enamel
• The only stage where no drilling is ever needed

Stage 2: Enamel cavitation

• The surface breaks; a small hole forms, still within enamel
• Usually still painless; treatment is a small, quick, inexpensive filling

Stage 3: Dentin decay

• Decay reaches the softer layer under enamel and moves faster - dentin is less mineralised
• Sensitivity to cold, sweet and hot begins; food catches in the hole
• Treatment is still a filling, but bigger - delay here shortens the tooth's future

Stage 4: Pulp involvement (pulpitis)

• Decay reaches the nerve: lingering pain, night pain, throbbing
• A filling is no longer enough - the tooth needs root canal treatment or, if too far gone, extraction

Stage 5: Abscess

• Infection exits the root tip into bone: severe pain on biting, a gum boil, facial swelling, fever
• Urgent dental care - antibiotics alone never fix it; the source (root canal or extraction) must be treated
• Rarely, the infection spreads further - facial swelling with fever is a same-day emergency

One-line summary

Decay's five stages - reversible white spot, enamel hole, dentin sensitivity, nerve pain, abscess - climb from "fluoride and habit change" to "root canal or worse", which is why the cheapest, easiest dental visit is the early one.