Purpose: The purpose of this study was to investigate the relationship between: (1) children's caries score (dmft, DMFT) at the time of sealant placement; and (2) "success" (measured as being caries-free) of that tooth at follow-up visits. Methods: An existing database of over 38,000 sealants (10,038 children) placed between 1997 and 2002 by the Jefferson County Health Department's Community Based Sealant Program, Birmingham, Ala, was used in the analysis. Only children returning for follow-up visits after the initial placement of the sealants were included in this study, resulting in 6,452 sealants (2,097 children). Logistic regression analysis was performed to determine the differences in sealant success between children with a dmft score of 0 vs a dmft score of >0 at baseline, and a DMFT score of 0 vs a DMFT score of >0 at baseline. Results: In the permanent and primary dentitions, those who had no caries at the time of sealant placement (dmft/DMFT=0) had a significantly higher success of sealants during years 1 to 5 compared to those with a caries score of greater than 0 (dmft/DMFT>0; P<.023, P<.002, respectively). Conclusion: Children with previous caries experience may be at a higher risk for sealant "failure" (measured as caries on a tooth surface previously sealed) after 1 year and, therefore, may require more diligent sealant maintenance.