Prevalence of dental caries in Indiana school children: results of 1982 survey.

During the 1981-82 school year, 6,363 Indiana school children in grades 1-12 were examined to determine caries prevalence and its relationship to geographic area, type of residence, water fluoride history, age, and sex. The results compare favorably with those observed in Region III of the NIDR national caries survey. When compared to a similar survey conducted in Indiana 10 years earlier, the present data reflect a decreased caries prevalence in both the permanent and primary dentitions. During the past 23 years caries prevalence in Indiana has declined nearly 70%. Since 1958, statewide surveys of the.prevalence of dental caries in Indiana school children have been performed at 10to 13-year intervals. The most recent survey was conducted during the first half of 1982. Its primary objective was to determine caries prevalence on the basis, of geographic area, type of residence, water fluoride history, age, and sex. This article summarizes the observations obtained from the latest survey. Methods and Materials School Selection During the 1981.-82 school year, 6,363 children in 134 schools, grades 1-12 were examined to determine dental caries prew~lence. The schools and grade levels examined were chosen randomly using a weighted sampling procedure based on a stratified listing of all public and parochial schools. 2-6 The schools were stratified into various categories to reflect their geographic location (northern, central, or southern), type of residence (urban or rural), and water fluoride content (fluoridated or nonfluoridated). Geographic location was based on the boundaries used by the Health Service Agency (HSA). Urban areas were defined arbitrarily as those cities with a population of 10,000 or greater based on the 1980 census. 7 Information regarding water fluoride content was derived from various lists and maps provided by the Dental Division of the Indiana State Board of Health. ~12 Fluoridated water was defined as having at least 0.8 ppm fluoride. Lifetime exposure to fluoridated water was considered to be exposure (residence) for at least 92% of the participant’s life. Age was defined as the child’s age at the time of examination and sex was obtained from the health history questionnaire. Participant Selection Once initial approval was obtained from the superintendants and principals of the selected schools, arrangements were made to conduct the examinations. A consent letter/health history was provided to each student in the chosen grade levels. Examinations were performed only on those students who returned a completed health history/consent form and who had a negative health history. Examination Team and Equipment The examining team consisted of a single examiner and a recorder. Examiner calibration with an experienced clinical examiner was conducted to establish diagnostic consistency before the survey was begun. Diagnostic criteria were those described by Radike in 1968.13 The field equipment included a portable dental light, 8 CARIES PREVALENCE IN INDIANA SCHOOL CHILDREN: Stookey el al. dental chair, plane surface mirrors, double-ended explorers, and compressed air. The caries examinations were performed without radiographs and each student’s teeth were brushed with a dentifrice prior to examination to remove oral debris. Findings were recorded in terms of DMF and def teeth and surfaces. The data then were transferred to punch cards for cybernetic analysis and tabulated according to age, sex, type of residence, and water fluoride history.