Fissures are the grooves that naturally occur on the biting surfaces of teeth.
Commonly, molars and premolars have fissures to some degree. Occasionally, fissures occur on canines and incisors.
If the fissures are very deep and narrow, toothbrush bristles cannot fit inside to clean out food particles. Trapped food attracts bacteria, which multiply within the fissures and make a sticky coating called plaque. Plaque acid then eats into the tooth enamel and causes decay.
Not all fissures are prone to decay, only the deepest and narrowest fissures are at risk.
A fissure is five times more likely to develop decay than other tooth surfaces. In children and adolescents, the chewing and grinding surfaces of molars and premolars are the most vulnerable.
Fissure sealants are polymer coatings that fill the fissures and protect teeth from dental plaque and acids. Glass ionomer cements may be used as an alternative material.
Many studies have shown that fissure sealants are effective in reducing the occurrence of tooth decay. On a tooth surface with completely sealed fissures, protection is 100%. As a fissure sealant wears down though, the protection is reduced. However even after five years, a protected tooth has half the risk of decay compared to an unprotected tooth.
Treatment is painless and non-invasive, with a coat of the sealant applied to a cleaned tooth. The liquid sets in minutes and forms a physical barrier that stops food, bacteria and plaque acids from contacting the tooth surface. Fissure sealants can be white, clear or tinted.