The deficiency of which one of the following leads to dental caries?

Dental caries, or tooth decay, is primarily caused by the demineralization of tooth enamel due to acids produced by oral bacteria [c1, c3]. Fluorine (in the form of fluoride) is essential for preventing this process as it increases the resistance of enamel to acid attacks [t1]. Fluoride interacts with calcium phosphates to enhance the structural stability of teeth and bones, promoting mineralization and re-mineralization [t8]. While excess fluoride intake can lead to dental fluorosis or skeletal issues [c2, c5], a deficiency—specifically levels below 0.1 mg per liter in drinking water—is a significant risk factor for the development of dental caries [t3]. Fluoride's role in dental health was first widely recognized in the 1930s, leading to its use in toothpastes and water fluoridation to reduce decay [t4]. Other elements like iron, copper, and zinc do not have the same direct protective relationship with enamel integrity.

Sources

1. [1] Science , class X (NCERT 2025 ed.) > Chapter 5: Life Processes > Dental caries > p. 86
2. [2] Science , class X (NCERT 2025 ed.) > Chapter 2: Acids, Bases and Salts > pH change as the cause of tooth decay > p. 27
3. [3] Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 29: Environment Issues and Health Effects > ag.l.s.Fluorine > p. 414
4. [4] Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 5: Environmental Pollution > 3. Hazards of ground water pollution: > p. 76