In the aforementioned study, when the healthy and peri-implantitis patient groups were combined, subjects who tested negative for IL-1 exhibited higher levels of IL-1β and PGE2 in the PICF than those who tested positive for IL-1 (p = 0.02 for IL-1β and p = 0.04 for PGE2). Here, IL1A is linked to Peri-Implantitis.