Mendes VS, et al. - In this case-control study, authors investigated 397 patients with psoriasis and 359 controls see if there was a relationship between psoriasis and periodontitis. Among patients (46.1%) vs controls (33.1%) they noted a high occurrence of periodontitis. As the severity of psoriasis increased, so did the prevalence of periodontitis, and significantly so (mild form [44.4%]; moderate [46.3%]; and advanced [47.1%]) vs the control group (33.1%). Occurrence of periodontitis was also reported to be significantly related with the number of teeth, smoking, and body mass index.