RESUMO
Bone morphogenetic proteins (BMPs) play an important role during the initial process of enamel development and therefore may play a role in caries susceptibility. The purpose of this study was to evaluate the association between the polymorphisms in the BMP2, BMP4 and BMP7 genes and their association with caries experience and primary enamel microhardness characteristics. DNA from buccal cells as well as clinical and demographic information from 1,731 subjects from three different data sets from Brazil were included. Polymorphisms in BMP2, BMP4 and BMP7 were analyzed by real-time polymerase chain reaction from genomic DNA. Association between caries experience, genotype, and allele distribution in both cohorts was evaluated using χ(2) and logistic regression analyses. In the family-based set, the association between caries experience and alleles was tested using the transmission disequilibrium test. In the Rio de Janeiro cohort, microhardness data on 108 exfoliated primary teeth before and after demineralization and remineralization challenges was included. Associations between microhardness values and genotype and allele distribution were evaluated using χ(2) and logistic regression analyses. Differences between caries experience and some risk factors were statistically significant. In the cohort from Nova Friburgo, BMP2 was associated with caries experience in primary dentition during logistic regression analysis (p = 0.023; OR = 2.58; 95% CI 1.13-5.86). There was no association between genotype and allele distribution for BMP polymorphisms and primary enamel microhardness alterations. Our result suggests that BMP2 may be involved in caries experience in primary dentition from a Nova Friburgo cohort.