Deep pits and grooves can be found on the chewing surfaces of the back teeth. Such pits and grooves are termed 'fissures' and are usually so narrow that toothbrush bristles and streams of water are not able to clean them effectively.
Fissure sealants can be applied to the teeth. Fissure sealants are special materials used by dentists to seal off pits and fissures from the oral environment. Sealing the tooth surface protects fissures from bacteria and fermentable foods like sugar and starches to prevent decay from starting deep within the fissures.