A Comparative Study of α-Defensin 3 and Cathepsin G Concentrations in the Saliva of Children with Early Childhood Caries and Caries-Free Children

Abstract

Background: The importance of saliva in preventing caries has been well established. Saliva contains several antimicrobial proteins. Objectives: The present study aims to compare the concentrations of α-defensin 3 and cathepsin G in the saliva of children with early childhood caries (ECC) and those who are caries-free (CF). Methods: This case-control study was conducted on 80 children aged 3 to 6 years, referred to the pediatric dentistry department of Shahid Beheshti University of Medical Sciences, Tehran, Iran, between April 2018 and December 2018. The participants were divided into two groups: The ECC (n = 40) and CF (n = 40). After collecting saliva samples, the levels of α-defensin 3 and cathepsin G were measured using the enzyme-linked immunosorbent assay (ELISA) method. The data were analyzed with SPSS-21 software using an independent t-test and chi-square test. Results: The mean concentrations of α-defensin 3 and cathepsin G in the ECC group were 92.88 pg/mL and 139.40 pg/mL, respectively, and 64.68 pg/mL and 65.30 pg/mL in the CF group. Initial unadjusted analysis revealed that both markers had a statistically significant difference (P < 0.001). According to the results of the multiple logistic regression model, after adjusting for underlying variables [parents’ education, gender, age, Plaque Index (PI), and type of nighttime feeding], cathepsin G (P = 0.022), father’s education (P = 0.033), and PI (P = 0.018) showed statistically significant differences between the two groups. Also, α-defensin 3 concentration showed no statistically significant difference between the two groups after adjustments (P = 0.058). Conclusions: The results showed that while the levels of cathepsin G and α-defensin 3 in the saliva of preschool children with ECC were increased, only cathepsin G remained statistically significant after adjustments.