Atraumatic restorative treatment-sealed versus nonsealed first permanent molars: a 3-year split-mouth clinical trial

To investigate the efficacy of atraumatic restorative treatment (ART) sealants vs. no sealant in preventing the development of dentine caries lesions in first permanent molars over a period of 3 years. A total of 187 schoolchildren (aged 6–8 years) from a low-income population presenting the 4 first permanent molars without clinically detectable dentine caries lesions were selected to be part of a split-mouth clinical trial. All 4 first permanent molars were investigated in this trial and the children’s mouth was split vertically into left and right sides; therefore, 2 molars were randomly allocated to receive ART sealants, while the other 2 molars remained nonsealed. All children received toothbrushing instructions and dietary advice every 6 months for a period of 3 years. Clinical evaluations were performed after 3, 6, 12, 18, 24, and 36 months and both sealant retention and dental caries were scored. Kaplan-Meier survival analysis, log-rank test, and Cox regression with shared frailty analysis were performed. A cavitated dentine caries lesion was considered a failure. The cumulative survival rates of dentine cavity-free first permanent molars were 90% for ART-sealed molars and 90.8% for nonsealed molars, with no statistically significantly difference between sealed and nonsealed molars (p = 0.70). The retention of sealants was not associated with the development of cavitated dentine caries and children presenting a higher baseline caries experience had greater chances of developing dentine lesions. In conclusion, the application of ART sealants was not more efficacious than nonsealing in reducing the development of dentine cavitated lesions in first permanent molars