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Tamil Nadu Board of Secondary EducationSSLC (English Medium) Class 8

Heshna and Keerthi are friends. Keerthi’s teeth are white without caries, but Heshna has teeth with caries. Why? How is it formed?

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Question

Heshna and Keerthi are friends. Keerthi’s teeth are white without caries, but Heshna has teeth with caries. Why? How is it formed?

Answer in Brief
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Solution

  1. Caries are caused by the action of acids on the enamel surface.
  2. The acid is produced when sugar in foods or drinks reacts with bacteria present on the tooth surface.
  3. Heshna has not cleaned her teeth well after sipping sugary drinks and snacking.
  4. She has to brush after meals and before bed.
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Chapter 14: Acids and Bases - Exercises [Page 165]

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Samacheer Kalvi Science [English] Class 8 TN Board
Chapter 14 Acids and Bases
Exercises | Q VI. 2. | Page 165

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