They are special coatings placed in the premolar and molar chewing surface to prevent tooth decay. These structures have fissures that would make them vulnerable when they are deep and difficult to clean. When this happens, plaque tends to accumulate in the area and starts attacking the dental structure. They are usually made to protect children’s teeth from decay, but they should be placed after teeth have completely erupted from the gum. They usually last for many years, but it is advisable to have them checked regularly.