FN1 and cystic fibrosis: Regarding fibronectin, a slightly higher concentration was reported in CF patients in this investigation (CF: 20.43 IQR 13.8–34.2) compared to children with certain level of caries (16.7; IQR 11.9–41.1) (p = 0.7), being lower in children with a higher caries index (CA2 16.2 IQR 12.3–17.9) (Figure 2C and 2D), although no statistically significant differences were detected between these three groups (p = 0.7).