Haplotypes in BMP4 and FGF Genes Increase the Risk of Peri-Implantitis

Despite the success of osseointegrated implants, failures have increased significantly, associated with development of peri-implantitis. Multiple factors influence the peri-implant bone loss, including environmental and genetic causes. BMPs (Bone morphogenetic proteins) are growth factors that induce bone formation. FGF (fibroblast growth factors) and their receptors (FGFRs) play important roles by controlling the levels of cell proliferation, differentiation and migration. BMP/FGF relationship is responsible for promoting bone regeneration and bone loss. The aim of this study was to analyze the correlation between BMP4, FGF3, FGF10 and FGFR1 genes and peri-implant bone loss. Two hundred and fifteen volunteers, with 754 dental implants, were submitted to oral examination and divided in healthy group (n=129) and peri-implantitis group (n=86). Thirteen polymorphisms in BMP4, FGF3, FGF10 and FGFR1 genes were analyzed individually and in haplotype. The chi-square test correlated genotypes, allelic and haplotype frequencies. Values of p<0.05 were considered significant. Volunteers with peri-implantitis demonstrated high incidence of total edentulism (p<0.0001) and thin peri-implant phenotype (p<0.04). Higher incidence of spontaneous bleeding, plaque and implant mobility was observed in peri-implantitis group (p<0.0001 for all). The TT polymorphic genotype for BMP4 rs2761884 was associated with healthy peri-implant (p=0.01). FGF3 rs4631909 (TT+CT genotype) also showed association with the control group (p=0.04). The frequency of C allele for FGF3 rs4631909 showed a tendency for association with peri-implantitis (p=0.08). FGF10 CCTG (p=0.03), BMP4 GAAA (p=0.05) and GGGA (p=0.02) haplotypes were associated with peri-implantitis (p=0.03). Therefore, it may be concluded that BMP4 and FGF10 haplotypes are associated with peri-implantitis.