Why does fluoride prevent cavities?
In general, three conditions must be present to produce dental cavities (also called caries). They are microorganisms, a carbohydrate diet for the microorganisms, and a susceptible tooth structure. Fluoride is an ideal caries-preventive agent, because it acts on each of these conditions. Though not proven definitively, fluoride kills bacteria or helps control bacterial growth, enhances remineralization so that minerals are more readily deposited into damaged areas of the tooth, and reduced enamel solubility making the enamel stronger to resist decay. Common modes of fluoride delivery include water fluoridation, dietary fluoride supplements, professionally applied fluoride on the surface of the teeth and self-applied fluoride (rinse or gel). Like any substance, fluoride is beneficial in proper amounts and harmful in excessive amounts.
What is gingivitis?
Gingivitis is an inflammation of the gingiva or “gums” and is so common that is affects almost all people at some time in their life. Though gingivitis is the early stage of more serious tooth disease, it is reversible! The major cause of gingivitis is plaque, a soft, sticky, almost colorless bacterial film that forms continuously on your teeth. The bacteria in plaque produces toxic substances that can irritate the gums and lead to gingivitis. To control gingivitis, first you must control plaque. Pain is not a common warning signal of gingivitis. Signs to look for are red, swollen, or bleeding gums.
Why are my teeth so sensitive along the gum line?
Estimates are as high as 25% of adults in the U.S. have some tooth sensitivity. Many teeth are especially sensitive along the gum line due to dentin exposure. Dentin is the inner sensitive part of your teeth. It composed of thousands of fluid-filled tubules that lead straight to the nerves that perceive pain. The pain experienced due to dentin exposure can be mild or intense. Dentin is usually covered by enamel covering the crown or cementum covering the root. In about 10% of teeth, the enamel and cementum do not meet, causing the dentin to be exposed. Normally, the gum tissue will cover the exposed area and prevent tooth sensitivity. However, gum disease, gum recession due to excessive brushing, or tooth wear at the gum line due to excessive clenching or grinding will lead to dentin exposure. If you do have sensitive teeth, tell your dentist. There are in-office treatments, such as bonding, to cover the exposed dentin. Toothpaste formulated to protect against tooth sensitivity might be useful. The toothpaste works by plugging the exposed tubules with a compound, such as potassium nitrate. It may take 2-3 weeks of frequent use of toothpaste to notice a difference in tooth sensitivity.