Relationship among α amylase and carbonic anhydrase VI in saliva, visible biofilm, and early childhood caries: a longitudinal study

Aim This longitudinal study investigated the relationship among early childhood caries (ECC), α amylase, carbonic anhydrase VI (CA VI), and the presence of visible biofilm, besides detecting if these variables could predict risk for ECC. Design One hundred children were divided into two groups: caries group (n = 45) and caries‐free group (n = 55). Visible biofilm on maxillary incisors was recorded, followed by caries diagnosis in preschoolers at baseline and at follow‐up. Saliva samples were collected, and activities of CA VI and α amylase were determined. Data normality was assessed by Shapiro–Wilk test and then Mann–Whitney, Spearman correlation, and chi‐square tests followed by multiple logistic regression analysis (α = 0.05, 95% confidence interval). Results CA VI activity was significantly higher in saliva of children with caries (P ≤ 0.05), and α amylase activity was significantly higher in saliva of caries‐free children (P < 0.0001). Children with α amylase activity in saliva lower than 122.8 U/mL (OR = 3.33 P = 0.042) and visible biofilm on maxillary incisors (OR = 3.6 P = 0.009) were more likely to develop ECC than caries‐free children. A negative correlation between caries and α amylase activity was found (P = 0.0008). Conclusions The presence of visible biofilm and low salivary activity of α amylase may be considered risk predictors for ECC.