External validation of an artificial intelligence-based method for the detection and classification of molar incisor hypomineralisation in dental photographs

Objectives: This ex vivo diagnostic study aimed to externally validate an open-access artificial intelligence (AI)based model for the detection, classification, localisation and segmentation of enamel/molar incisor hypomineralisation (EH/MIH). Methods: An independent sample of web images showing teeth with (n = 277) and without (n = 178) EH/MIH was evaluated by a workgroup of dentists whose consensus served as the reference standard. Then, an AI-based model was used for the detection of EH/MIH, followed by automated classification and segmentation of the findings (test method). The accuracy (ACC), sensitivity (SE), specificity (SP) and area under the curve (AUC) were determined. Furthermore, the correctness of EH/MIH lesion localisation and segmentation was evaluated. Results: An overall ACC of 94.3 % was achieved for image-based detection of EH/MIH. Cross-classification of the AI-based class prediction and the reference standard resulted in an agreement of 89.2 % for all diagnostic decisions (n = 594), with an ACC between 91.4 % and 97.8 %. The corresponding SE and SP values ranged from 81.7 % to 92.8 % and 91.9 % to 98.7 %, respectively. The AUC varied between 0.894 and 0.945. Image size had only a limited impact on diagnostic performance. The AI-based model correctly predicted EH/MIH localisation in 97.3 % of cases. For the detected lesions, segmentation was fully correct in 63.4 % of all cases and partially correct in 33.9 %. Conclusions: This study documented the promising diagnostic performance of an open-access AI tool in the detection and classification of EH/MIH in external images. Clinical significance: Externally validated AI-based diagnostic methods could facilitate the detection of EH/MIH lesions in dental photographs.