Tooth decay, also known as dental caries or cavities, is a bacterial infection that causes demineralization of tooth enamel, leading to damage and potentially painful cavities. Causes 1. *Poor oral hygiene*: Infrequent brushing and flossing. 2. *Sugary or acidic foods and drinks*: Consuming high amounts of sugar or acid can contribute to tooth decay. 3. *Dry mouth*: Low saliva flow can increase the risk of tooth decay. 4. *Genetic predisposition*: Some people may be more susceptible to tooth decay due to genetic factors. Symptoms 1. *Tooth sensitivity*: Pain or discomfort when consuming hot or cold foods and drinks. 2. *Toothache*: Pain or discomfort in the tooth or surrounding area. 3. *Visible holes or pits*: Cavities or holes in the teeth. 4. *Discoloration*: White, brown, or black spots on the teeth. Prevention 1. *Regular brushing and flossing*: Maintain good oral hygiene habits. 2. *Fluoride use*: Use fluoride toothpaste and mouthwash to strengthen teeth. 3. *Healthy diet*: Limit sugary and acidic foods and drinks. 4. *Regular dental check-ups*: Visit the dentist regularly for cleanings and check-ups. Treatment 1. *Fillings*: Restoring teeth with fillings, such as amalgam or composite resin. 2. *Crowns*: Covering teeth with crowns to protect them from further damage. 3. *Root canal therapy*: Treating infected pulp and nerves. 4. *Extraction*: Removing severely decayed or damaged teeth.