RESUMO
BACKGROUND: Matrix metalloproteinases and their inhibitors might be involved in enamel formation. AIM: This study aimed to evaluate the association between polymorphisms in MMP2, MMP3, MMP9, MMP20, TIMP1, and TIMP2 with white spot lesions (WSL) and early childhood caries (ECC). DESIGN: A cross-sectional study was performed on 786 children aged from 2 to 6 years in Brazil. After clinical evaluation, they were classified into groups with disease (the presence of WSL and/or ECC) and without disease (the absence of WSL or ECC). Genotyping of the selected polymorphisms was carried out with TaqMan real-time PCR, using genomic DNA extracted from buccal cells. Allele and genotype frequencies were compared between groups. Chi-square test, odds ratio (OR), and logistic regression were used (P ≤ 0.05). RESULTS: The dmft score was 1.3 (SD: 2.4), and 41.34% of the children have at least one caries lesion. In MMP9, the GG genotype was more frequent in the group without disease (P = 0.006). In a recessive model, WSL was associated with the marker rs1711437 in MMP20 (P = 0.019; OR = 1.20, 95% CI 1.02-1.42). The marker rs1784418 in MMP20 showed an association between the allele G distribution for the WSL group (P = 0.020; OR = 0.73, 95% CI 0.55-0.96). CONCLUSION: MMP9 and MMP20 are involved in WSL and ECC development.