Oligodontia is a rare condition, and only limited data are available on its prevalence. The present paper is based on data from Danish schoolchildren. When these data are combined with comparable data on Danish schoolchildren published previously by the senior author, it is shown that oligodontia occurs in 0.16% of the children (95% confidence interval, 0.07% to 0.30%). Two of every three congenitally missing teeth were upper or lower second premolars or upper lateral incisors. When data from Danish schoolchildren were combined with population data from similar groups of schoolchildren from the Nordic countries, the condition was found to be more frequent in girls than in boys (P = 0.05).