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Where does tooth decay commonly begin on a tooth?
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tooth
Cross section of an adult human molar.
Tooth decay, also known as caries, typically originates on the surface of the tooth. It most commonly begins in the pits and fissures of the enamel or in the spaces between adjacent teeth.1
This process is driven by the buildup of plaque, a yellowish film that harbors bacteria. These bacteria ferment sugars and starchy food debris into acids, which then dissolve the minerals in the tooth's enamel and dentine. Once the decay breaches the surface enamel, it can spread into the underlying dentine and potentially reach the pulp at the center of the tooth.213