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What is Caries? [Caries]

Caries is a disease in which teeth dissolve due to acid produced by Streptococcus mutans. Caries can be reversed through self-care during the stage of “early caries”. However, once a hole develops in the tooth, tooth decay will progress along with the caries, and it will become more and more difficult to treat.

points to note
  • Early caries can be improved through self-care. Try to practice preventive measures on a routine basis.
  • Carefully brush areas such as the bite surface between molars or between teeth where plaque easily accumulates and areas that are difficult to brush, since such areas are more susceptible to caries.

Characteristics of Caries

Early Caries

Minerals composing teeth have leached out of the teeth and the enamel interior has become hollow (subsurface decalcification)What is Early Caries?

Your tooth will not suddenly develop a hole after being affected by caries; however, if plaque is left on the surface of the tooth, acid produced by Streptococcus mutans, which causes caries, will dissolve the calcium or phosphorus components of the tooth, and they will be leached out of the enamel. This is called decalcification. If plaque is left to accumulate on the tooth, decalcification will progress, eventually causing the interior of the enamel to become hollow. This condition, one step short of developing caries, is called “early caries”.

Areas Susceptible to Caries

Plaque easily accumulates in areas such as between teeth or the chewing surfaces between molars, and hard-to-brush areas such as the tooth roots or around fillings, making the areas susceptible to caries. Brush the following areas very carefully.

Areas Susceptible to Caries (chewing surfaces between molars, between teeth, gum lines, where teeth overlap, tooth roots, where a denture is used, the joint of an artificial tooth, around fillings, around a crown, around the dental bridge, etc.)Areas Susceptible to Caries

Caries in Children’s Teeth, Caries in Adult Teeth

The surfaces of newly erupting permanent teeth easily become dirty and are hard to clean, due to their coarse texture. In addition, the tooth substrate has not fully matured yet. For these reasons, they are susceptible to caries. Among the types of caries that affect adult teeth, there is caries that occurs around fillings after treatment or around a dental crown (secondary caries), and caries that occurs at the root of a tooth (root surface caries).

Caries in Children’s Teeth

If caries in milk teeth is left untreated, it will affect the alignment of the permanent teeth. Milk teeth have the important role of securing space for permanent teeth, and if a milk tooth is badly affected by caries or is lost at an early stage, it may cause the teeth alignment to become crooked or cause a shortage of space in which permanent teeth can erupt.

If the tip of the root of a tooth that is badly affected by caries becomes filled with pus, it may affect the permanent tooth just below.

If caries of a milk tooth is severe and the focus is at the tip of the tooth root, it may affect the tooth substrate of the permanent tooth just below the milk tooth.

If a milk tooth is lost at an early stage, the teeth adjoining the milk teeth may move and reduce the space in which the permanent tooth can erupt.

If a milk tooth is lost at an early stage, the teeth adjoining the milk teeth may move and reduce the space in which the permanent tooth can erupt.

Caries in Adult Teeth

Caries in Teeth that have Been Treated (Secondary Caries)

Secondary caries caused by plaque that has accumulated around a filling after treatment or a crown is placed over the treated areaSecondary Caries

This type of caries is caused by plaque that has accumulated around a filling after treatment or a crown is placed over the treated area. It is often more advanced by the time it is noticed. You cannot let down your guard simply because your teeth have been treated once.

Caries that Occurs at the Tooth Root (Root Surface Caries)

Root surface caries that occurs at the root of an exposed toothRoot Surface Caries

This type of caries occurs at the root of an exposed tooth, due to the progression of periodontal disease or inappropriate tooth brushing. At the root of a tooth, plaque tends to remain after brushing and the tooth substrate is soft, so this area should be brushed carefully.