The prevalence and sex ratio of juvenile periodontitis in a young racially mixed population.

The need to accurately determine the prevalence of a disease is important especially in establishing treatment needs for particular population groups. Reported prevalences for juvenile periodontitis (JP) have varied from less than 0.1% to 17%. The use of overall prevalence values to determine treatment needs in populations which include various ethnic groups is not reliable since there is evidence that the prevalence in different groups is unequal. The purpose of this study was to determine the prevalence and sex ratio of JP in a large group of military recruits and to compare these values between the different racial populations. Thirty-eight cases of JP were diagnosed from a group of 5,013 young male and female recruits of varying ethnic origin. The overall prevalence was 0.76% and the female:male ratio 1.1:1.0. These findings raise questions as to the continued quotation of a female:male ratio of 3:1, and provide additional evidence for an overall ratio closer to 1:1. In addition, prevalences of JP varied considerably between racial groups. Blacks had a much higher JP prevalence (2.1%) than caucasians (0.09%). Black males had a higher prevalence (3.81%) than black females (1.99%). For black recruits the F:M ratio was 0.52:1. For caucasian recruits the F:M trend is opposite (4.3:1), although the number of cases diagnosed in the caucasian group was too low to compute a true ratio. The data support studies which show that in the blacks, the disease is less prevalent in females than in males. Caution must be exercised in interpreting results in any study in which the sample population is not categorized.