Fluoride anions are negatively charged ions formed when a fluorine atom gains an electron. They are represented by the chemical symbol F⁻. Fluoride is commonly found in nature, particularly in minerals and water sources, and plays a significant role in dental health by helping to prevent tooth decay. In addition to its dental benefits, fluoride anions are used in various applications, including toothpaste and mouth rinses. They can also be found in some drinking water supplies, where they are added to promote oral health. However, excessive fluoride exposure can lead to health issues, such as dental fluorosis.