Dental caries diagnosis calibration for clinical field surveys.

A method to calibrate examiners for field studies of dental caries was investigated. A total of 200 carious teeth were mounted in 40 plaster blocks so that 920 surfaces were available for examination with a curved probe, using WHO criteria. The results of two examinations of the teeth 1 week apart by 3 experienced and 4 new examiners and 1 year apart by two experienced examiners were compared. The intra-examiner and inter-examiner reproducibility was high for the experienced examiners; between experienced and new examiners the reproducibility fluctuated. Scanning electron microscopic examination of the tips of probes indicated that the sharpness was only slightly decreased within their usual frequency of use. The calibration system used is recommended for the training of examiners for dental caries field studies.