Question

A dental disease characterized by mottling of teeth is due to the presence of an ingredient in drinking water namely
(a) Fluorine
(b) Mercury
(c) Boron
(d) Chlorine

Answer 1

This is the lightest halogen and a chemical element, with the symbol F and its oxide is used as an ingredient in toothpaste. The atomic number is 9 and it is the most electronegative element. At standard conditions, it remains in a gaseous state.

Correct step by step answer:
A dental disease characterized by mottling of teeth is due to the presence of an excess of fluoride in drinking water. Mottling of teeth occurs in dental fluorosis. The hypomineralization of tooth enamel is a common disorder caused by the ingestion of excessive fluoride during enamel formation that is the first eight years of life. This is the time when most of the permanent teeth are formed. The main characteristics of this dental disorder are staining or discoloration and pitting of teeth.
- If the disorder is more severe it may cause damage to all the enamel, sometimes teeth are also physically damaged. The early symptoms of dental fluorosis include pain and stiffness in the joints of the jaws.
- Consumption of excess mercury is related to the consumption of seafood. A small amount of mercury is present in everyday food products but in seafood, the amount of mercury is very high so people consuming too much seafood must have to face mercury poisoning.
- consumption of excess boron causes nausea, vomiting, indigestion, headache, and diarrhea.
- excessive exposure to chlorine causes a buildup of fluid in the lungs that is pulmonary edema. Sometimes may cause abdominal cramping, diarrhea, food poisoning, or stomach flu.

Note:
- Very mild dental fluorosis shows small, opaque, paper white areas scattered irregularly over the tooth.
- In moderate dental fluorosis all animal surfaces of the teeth are affected and a brown stain over the teeth is seen.
- In case of severe dental fluorosis the brown stains are like appearance.