Cavities, commonly known as tooth decay, occur when bacteria produce acid that depletes minerals from teeth, gradually forming holes that deepen over time. Common sites: pits and fissures on occlusal surfaces, tooth surfaces, and tooth roots. If left untreated, cavities will spread from the outer layer to deeper tooth structures, potentially causing severe infection and toothache. When tooth damage becomes too extensive for restoration, tooth extraction will be necessary.
  1. Healthy Tooth:
Intact tooth surface.

2. Enamel Caries (Superficial Caries):
Plaque acids demineralize enamel to form shallow lesions. No thermal sensitivity or obvious pain, often undetected.

3. Dentin Caries (Moderate / Deep Caries):
Obvious cavities penetrate enamel into dentin. Hot/cold food triggers mild to sharp pain. Dentin is softer and more vulnerable to acid, accelerating decay.

4. Caries into Pulp Chamber:
Cavity reaches pulp chamber. Infected, swollen pulp compresses the nerve and causes intense pain, which may travel through the apical foramen to the alveolar bone.
 

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  Dental plaque, a film of bacteria and food debris, is the main culprit for both cavities and periodontal disease. Plaque bacteria ferment dietary sugars into acid, which depletes tooth minerals and creates expanding cavities. Insufficient daily cleaning (rinsing, brushing, flossing) and lack of regular professional cleanings allow plaque to accumulate and trigger cavities. Misaligned teeth or fixed braces hinder self-cleaning and increase caries risk.
 
1. Young Kids & Teens:
Minors with hypoplastic enamel have poor resistance to bacterial acid and are prone to cavities.

2. Tooth Wear:
Heavy enamel wear in older adults exposes dentin, increasing cavity risk.

3. Pregnancy:
Frequent intake of sweet or sour foods during pregnancy makes cavities more likely.

4. Dry Mouth:
Saliva helps neutralize bacterial acid. Some medicines reduce saliva flow and raise cavity risk.