Necessidade de tratamento ortodôntico: validação do DAI (Índice de estética dental) e do ICON (Índice de complexidade, resultado e necessidade) para a região de Belo Horizonte

Abstract

Orthodontic treatment need: validation of the DAI (dental aesthetic index) and the ICON (index of complexity, outcome and need) for the area of Belo Horizonte, BrazilOcclusal indices, such as the Dental Aesthetic Index (DAI) and the Index of Complexity, Outcome and Need (ICON) are used to determine eligibility for orthodontic treatment in public funded services. In Brazil, epidemiological surveys have assessed orthodontic treatment need prevalence by means of the DAI. The aim of this study was to investigate the validity of both indices for orthodontic treatment need in the area of Belo Horizonte, Minas Gerais. The DAI and ICON scores were compared to an aggregate opinion on treatment need formed by an expert panel of twenty specialists. A calibrated examiner in the DAI and ICON scored 108 study casts using the indices. The examiners and the panels reliability were assessed. Excellent ICC values were obtained for the DAI (rI 0,969) and ICON (rI 0,952). The the panel had interrater agreement levels that ranged from poor to good and intrarater levels ranging form poor to excellent. The accuracy measured by the area under ROC curve figured 81,83% for the DAI and 88,75% for the ICON. The difference between the areas under the ROC curves was significant (p=0,0435). The original cutoff points for the DAI (31) and ICON (43) were considered adequate when the desirable characteristics of a screening test for a low prevalence condition are taken into account. The specificity figures for DAI (86,67%) and ICON (93,33%) resulted in positive predictive values of 62,38% and 79,89%, respectively. The panel assigned 86% of the casts into treatment category. Using this high prevalence sample, the DAI classified 70,37% correctly. The ICON scores agreed with the panel 76,85% of the cases. The good accuracy levels achieved by both indices suggest DAI and ICON may be used so as to reflect the opinion of specialists from Belo Horizonte area.