The occlusal surfaces of all four first permanent molars were then thoroughly flushed with water to remove all traces of pumice slurry.
An explorer tine was used to remove as much residual plaque as possible from the occlusal surfaces of pits and fissures.
More effective measures are, therefore, necessary, such as application of occlusal sealants.Since 1920's several attempts have been made to protect pits and fissures, such as physical blocking of fissures with zinc phosphate cement, prophylactic odontotomy and fissures eradication were all tried, but with little success.
Nevertheless, these efforts to prevent pit and fissure decay succeeded only after 1955, when Buonocore published his classic study documenting a pioneer method for mechanical bonding of acrylic resin to the dental enamel previously etched with phosphoric acid.
Evaluation of sealant retention was performed at regular intervals over 12 months, using Simonsen's criteria at 2 month), 53.57% showed complete retention, 37.50% showed partial retention, and 8.83% showed complete missing of resin-based filled (Helioseal F) pit and fissure sealant.
They have been considered as the single most important feature leading to the development of occlusal caries.Out of 150 children examined, 56 children had fulfilled the inclusion criteria.