Aim: To determine the relationship between the chemical composition of saliva, periodontal disease and dental calculus. Methods: An observational analytical cross-sectional study was conducted with patients over 55 years of age. Ethical principles of autonomy and risk protection were applied according to the international standards. Sociodemographic and diagnosis variables (presence of dental calculus and periodontal status) were considered to measure salivary concentrations of glucose (by the glucose oxidase/peroxidase method, amylase (by the colorimetric test), urea (by the amount of indophenol), total protein (by the Bradford method) and albumin (by the nephelometric method). Patients chewed a sterile rubber band and 3 mL of stimulated saliva were collected. The samples were stored at -5 °C, centrifuged at 2,800 rpm for 10 min, and the supernatant was removed and stored at -20 °C. Data were presented as frequencies and proportions for qualitative variables and measures of central tendency and dispersion for quantitative variables. Data were analyzed by either analysis of variance or Kruskal Wallis test . A p value <0.05 was considered statistically significant. Results: Significant relationships were observed between the concentration of salivary urea and periodontal status (p = 0.03) and the presence of dental calculus and urea (p = 0.04) was demonstrated. Conclusions: A relationship between the salivary urea concentration and the presence of periodontal disease and dental calculus is suggested.