Dental sealants are "plastic caps" that are placed onto molars. The durable, clear resin material is applied in liquid form. It hardens almost immediately, after which the sealant stays in place over the deep crevices that might harbor food debris and bacteria. This treatment can be extraordinarily helpful for children who tend to get cavities easily. While the plastic material does wear down over time, this usually takes five years or longer. Many dental sealants can last about 10 years. During routine dental visits, the sealants are checked carefully to ensure they are in good working order. As needed, sealants can be reapplied.