Following the first National Oral Health Survey of Omani 12-year-olds in 1993, in 1996 a follow-up survey was performed of the same cohort of subjects as 15-year-olds. The mean DMFT was found to have doubled from 1.5 to 3.2. The oral hygiene status remained poor with only a slight increase of those scored as plaque-free from 11% to 19% whilst the number of children reportedly with supra-gingival lingual calculus had risen from 28.5% to 42.5%.