The Role of Oxidative Stress-Related Gene Polymorphisms (SOD2, GPX1) in Severe Early Childhood Caries (S-ECC)

<i>Background and Objectives</i>: Severe early childhood caries (S-ECC) is a chronic infectious disease with a multifactorial etiology which has not been completely elucidated. Research on the role of oxidative stress in the etiopathogenesis of oral diseases suggests that the level of local antioxidants plays an important role in determining susceptibility to caries. This study aimed to demonstrate that the host's redox imbalance, modified by genetic polymorphisms, may influence the onset and severity of S-ECC. <i>Materials and Methods</i>: A total of 110 patients were included in the study (59 diagnosed with S-ECC and 51 healthy controls). Upon initial appraisal, the DMFT (decayed-missing-filled teeth) index was determined, and epithelial cells were collected using oral swabs for genomic DNA extraction. Genotyping of <i>SOD2</i> (rs4880) and <i>GPX1</i> (rs1050450) was performed using TaqMan SNP genotyping assays and real-time polymerase chain reaction (PCR). <i>Results:</i> According to the results of the present study, there was a significant difference between the frequency of the reference genotype and variants for <i>rs4880</i> (<i>p</i> = 0.0303). Subjects carrying the AG and GG variant genotype of <i>rs4880</i> were significantly associated with a high DMFT value (<i>p</i> = 0.0005). However, no significant difference was found between the genotypes for <i>rs1050450</i>, nor was there an association with the severity of S-ECC. <i>Conclusions:</i> The AG and GG variant genotypes of the <i>SOD2</i> polymorphism (rs4880) increase the severity of caries in preschoolers and predispose patients to develop carious lesions, especially when associated with certain feeding practices and infrequent toothbrushing. This observation emphasizes that host sensitivity to caries is a crucial factor in the onset and development of carious lesions in primary dentition, despite the main contributing factors to this pathology. The <i>rs1050450</i> polymorphism was not associated with the severity of S-ECC.