Use of the oral microbiota as screening test to identify children at risk for caries development. A systematic review of longitudinal studies.

This study investigated trends in oral microbiota composition (index test) that could indicate potential candidates to identify children at risk for dental caries development compared with visual/tactile examination (reference test). MEDLINE/PubMed, Web of Science, Embase, Scopus, Lilacs, SciELO, and Google Scholar databases were searched up to September 2025. Methodological quality was assessed by Newcastle-Ottawa Scale and QUADAS-2. Qualitative synthesis was performed using all included studies. Thirteen studies that assessed the oral microbiota composition through high-throughput sequencing platforms were included comprising 740 caries-free participants at the baseline. Alloprevotella spp. and Megasphaera spp. were exclusively highly abundant in children who developed caries, whereas Peptostreptococcus spp. was exclusively highly abundant in caries-free children. The diagnostic value of the oral microbiota composition showed specificity, sensitivity, accuracy, and area under the receiver operating characteristics curve ranging from 0.6 to 1.0, 0.75 to 0.90, 0.73 to 0.93, and from 0.51 to 0.94, respectively. High risk of bias was found for the index test. The available evidence does not support the use of oral microbiota composition as a screening test to identify children at risk for caries development. Studies conducted at the species level are likely to provide results with greater sensitivity and specificity, improving risk assessment and understanding of caries-associated microbiota (PROSPERO CRD42023495648).