The document discusses the endocrinology of sex hormones and their effects on the periodontium. It covers the main sex steroid hormones - androgens like testosterone, estrogens like estradiol, and progestins like progesterone. It describes their mechanisms of action, roles in various physiological conditions like puberty, menstruation, pregnancy, and menopause. Fluctuations in sex hormone levels during these conditions can impact the periodontal tissues by altering the subgingival microbiota and increasing vascular permeability and inflammation. The periodontium is identified as a target tissue for sex hormones.