If we consider the calculated AUC values, except for hsa-miR-4485-3p, hsa-miR-6073, hsa-miR-936 and hsa-miR-942-3p (all from CP salivary-exosomal samples), other 6 miRNAs are worthy for future study in confirming whether they are correctly targeting TLR4; and to construct the relationship between miRNAs-TLR4-periodontitis. The gene discussed is TLR4; the disease is periodontitis.