Salivary Lactate Dehydrogenase and Matrix Metalloproteinase-8 as Predictive Biomarkers in Early Childhood Caries: A Cross-sectional Study.

BACKGROUND: Early childhood caries (ECC) remains a prevalent and aggressive dental disease in preschool children, often progressing rapidly if not detected early. Traditional diagnostic methods are limited to visual and radiographic findings, which may identify lesions only after substantial demineralization. Salivary biomarkers such as lactate dehydrogenase (LDH) and matrix metalloproteinase-8 (MMP-8) have emerged as promising noninvasive indicators of early pathological changes in the oral environment. AIM: To evaluate salivary LDH and MMP-8 levels in preschool children with and without ECC and to assess their potential as predictive biomarkers. MATERIALS AND METHODS: A cross-sectional study was conducted on 80 children aged 3-6 years. Participants were divided into two groups: group I (caries-free, n = 40) and group II (with ECC, n = 40). Unstimulated saliva samples were collected and analyzed for LDH activity (spectrophotometric assay) and MMP-8 concentration [enzyme-linked immunosorbent assay (ELISA)]. Data were statistically analyzed using Student's t-test and Pearson's correlation. RESULTS: Mean salivary LDH levels were significantly higher in the ECC group (365.2 ± 42.8 U/L) compared to the caries-free group (228.5 ± 38.6 U/L, p < 0.001). Similarly, salivary MMP-8 levels were elevated in children with ECC (42.6 ± 5.4 ng/mL) vs controls (25.3 ± 4.7 ng/mL, p < 0.001). A positive correlation (r = 0.62, p < 0.001) was observed between LDH and MMP-8 levels in ECC cases. CONCLUSION: Elevated salivary LDH and MMP-8 levels are associated with ECC, suggesting their potential role as predictive biomarkers for early diagnosis and preventive interventions. HOW TO CITE THIS ARTICLE: Kommalapati V, Soorneedi N, Supraja AN, et al. Salivary Lactate Dehydrogenase and Matrix Metalloproteinase-8 as Predictive Biomarkers in Early Childhood Caries: A Cross-sectional Study. Int J Clin Pediatr Dent 2026;19(8):1030-1033.