Teeth
About the Teeth
Adults have 32 teeth: 8 incisors cutting, 4 canines tearing, 8 premolars crushing, 12 molars grinding including 4 wisdom teeth third molars. Children have 20 deciduous baby teeth. Each tooth has a crown visible enamel hardest substance in the body, dentin beneath, cementum on the root, and pulp inner chamber with nerves and blood vessels. Periodontal ligaments anchor teeth to alveolar bone. Tooth eruption begins at 6 months and completes by approximately 21 years. Dental caries cavities from bacterial acid demineralization are the most common chronic disease worldwide. Periodontitis gum disease is a major cause of tooth loss. Fluoride incorporated into enamel makes it more resistant to acid. Mature enamel contains no living cells and cannot regenerate once lost. Orthodontics corrects malocclusion.
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