Study of a fissure sealant in mentally retarded Canadian children.

The occlusal fissure of 812 permanent and primary posterior teeth of 160 retarded children were sealed with a fluid resin which was polymerized with an ultra-voilet lamp. A half mouth technique was used to evaluate the effectiveness of the sealant in the prevention of fissure caries. The 1st year, the sealant was retained intact on 73 percent of the permanent teeth and on 64 percent of the primary teeth. After 2 years, the sealant was retained intact on 61% of the permanent teeth and on 40% of the primary teeth. The retention of the fissure sealant was better on premolars than molars both in the 1stand in the 2nd year. A single application of the fissure sealant was effective in reducing fissure caries up to 2 years.