Diagnosis training and calibration for epidemiological studies on primary and permanent teeth with hypomineralization

The objective of this study was to assess the impact on diagnostic accuracy and Kappa values improvement during the three-phase training and calibration process for MIH/HSPM.

Thirty dentists were calibrated as examiners for diagnosis of Molar Incisor Hypomineralization (MIH) using Ghanim's index. The whole process was divided into three phases. Phase 1: three meetings with the dentists for the first diagnosis training and calibration (sessions 1a and 1b); phase 2: for a period of 1 month, the dentists started practicing MIH/HSPM diagnosis in the Basic Health Units and an online follow-up group was created to discuss cases and resolve doubts; phase 3: two meetings with the dentists for the second calibration (sessions 2a and 2b). A webpage with educational material was prepared as support during the whole process to improve the dentists' skills in diagnosing MIH/HSPM. The examiners' responses were compared to a gold standard and the Kappa value was obtained.

The average clinical criteria kappa value of the examiners was 0.76 ± 0.19 for the first calibration and 0.93 ± 0.07 (p < 0.05) for the second calibration. For the eruption criteria, the average kappa value was 0.89 ± 0.14 for the first calibration and 0.98 ± 0.08 for the second calibration. Extension criteria had an average kappa value of 0.59 ± 0.15 during the first calibration and 0.75 ± 0.14 during the second calibration.

This study demonstrated that the methodology used was an effective tool for improving the diagnostic accuracy of MIH/HSPM.