On the other hand, a recent case-control study involving 120 individuals with healthy implants and peri-implantitis found that the polymorphism in the IL-1ß receptor antagonist was more prevalent in the group of peri-implantitis patients (OR 3), although no statistically significant differences were observed in the proportion of altered alleles for IL-1β between the groups. This evidence concerns the gene IL1B and Peri-Implantitis.