The role of the fissure morphology in caries prevalence of the first permanent molar in Libyan children.

Dental caries is one of the commonest of all dental diseases and is the main cause of loss of teeth in young people. It is a common belief that the high caries susceptibility of occlusal surfaces of posterior teeth is directly related to the morphology of the pits and fissures. Occlusal fissures are deep invaginations of enamel, they can be classified into V-type: Wide at the top and gradually narrowing towards the bottom U-type almost the same width from top to bottom. I-type an extremely narrow slit IK-type extremely narrow slit associated with large space at the bottom Y-type wide at the top and suddenly narrowing towards the bottom.