The formation of deep mucosal pockets with inflammation of the peri-implant mucosa around dental implants is called peri-implantitis. Smokers treated with dental implants have a greater risk of developing peri-implantitis. This condition can lead to increased resorption of peri-implant bone. If left untreated, peri-implantitis can lead to implant failure. In a retrospective study conducted at the University of Vienna, the peri-implant tissue of smokers and non-smokers was compared. The smokers showed a higher score in bleeding index with greater peri-implant pocket depth and radiographically discernible bone resorption around the implant, particularly in the maxilla.