Background: Dental caries in the primary dentition has received renewed attention in recent years because caries in the primary dentition is predictive of later caries experience, and because of efforts to address early childhood caries. More detailed caries diagnostic criteria have been developed and used for the permanent teeth; however, such criteria have not been widely adopted for caries diagnosis in the primary dentition.
Methods: As part of the Iowa Fluoride Study, caries diagnostic criteria were developed specifically for the primary teeth. The criteria included noncavitated (d1) lesions and cavitated (d2-3) lesions. Examinations were conducted on 698 children in the primary dentition by two trained examiners who did duplicate examinations on 11 percent (n = 67) of these children.
Results: Interexaminer agreement for any d1 and any d2-3 lesions at the person level was 100 percent. At the tooth level for d1d2-3f, there was 98.5 percent agreement and kappa was .91. For d1 at the tooth level, agreement was 97.0 percent agreement and kappa = .24. For d2-3 it was 99.4 percent agreement and kappa = .81. Prevalence of untreated d2-3 was 16.5 percent, while that of d1 was 24.1 percent. Nearly 73 percent had no d2-3 or filled surfaces, while over 63 percent had no d1, d2-3, or filled surfaces. Decay experience was most common on the primary second molars. About 56 percent of untreated d2-3 decay was located in the pits and fissures, while 58 percent of d1 decay was located on smooth surfaces.
Conclusion: Despite some concern with reliability of diagnosing d1 lesions, it appears that the d1d2-3 criteria are informative and useful in assessing the primary dentition.