The aim of the present investigation was to evaluate the relationship between the receipt of orthodontic treatment and subsequent periodontal health. Data from 417 children who were classified at baseline as having significant occlusal variations and who were present at the follow-up examination 3 years later were selected from an original cohort of 1015. One hundred fourteen of these children received orthodontic treatment over this time period and provided two groups of children for comparison in this study. Plaque indices, bleeding indices, and degree of dental irregularity were recorded for each incisor and canine tooth. There were significant reductions in the plaque and gingivitis scores on all tooth surfaces between the baseline and 3-year examination in the two groups of children. The children who had received orthodontic treatment had the greater reduction, but this appeared to be more related to behavioral factors than to improved tooth alignment.