Several studies have demonstrated a strong relation between periodontal diseases and chronic kidney disease (CKD). The main mechanisms at the base of this link are malnutrition, vitamin dysregulation, especially of B-group vitamins and of C and D vitamins, oxidative stress, metabolic acidosis and low-grade inflammation. In particular, in hemodialysis (HD) adult patients, an impairment of nutritional status has been observed, induced not only by the HD procedures themselves, but also due to numerous CKD-related comorbidities. The alteration of nutritional assessment induces systemic manifestations that have repercussions on oral health, like oral microbiota dysbiosis, slow healing of wounds related to hypovitaminosis C, and an alteration of the supporting bone structures of the oral cavity related to metabolic acidosis and vitamin D deficiency. Low-grade inflammation has been observed to characterize periodontal diseases locally and, in a systemic manner, CKD contributes to the amplification of the pathological process, bidirectionally. Therefore, CKD and oral disease patients should be managed by a multidisciplinary professional team that can evaluate the possible co-presence of these two pathological conditions, that negatively influence each other, and set up therapeutic strategies to treat them. Once these patients have been identified, they should be included in a follow-up program, characterized by periodic checks in order to manage these pathological conditions.

Among the chronic non-communicable degenerative diseases (CDNCDs), chronic kidney disease (CKD) represents a global public health problem. Recent studies demonstrate a mutual cause–effect relationship between CKD and oral diseases, in which the presence of one induces the onset and faster progression of the other. In particular, the oral cavity alterations more frequent in CKD patients are: chronic periodontitis diseases, bone lesions, oral infections, and oral cancer lesions. Currently, a standardized therapy for the treatment of oral diseases is lacking. For this reason, natural bioactive compounds (NBCs), characterized by several health effects, such as antioxidant, antimicrobial, anti-inflammatory and anti-cancer actions, represent a new possible adjuvant therapy in the management of these pathological conditions. Among NBCs, polyphenols play a leading role due to positive modulation of oral microbiota, preventing and correcting oral dysbiosis. Moreover, these compounds exert anti-inflammatory effects, such as inhibiting the production of pro-inflammatory cytokines and the expression of cycloxigenase-2. In this light, the formulation of a new mouthwash/gel/gingival paste, with a high content of polyphenols in association with NBCs characterized by antimicrobial action, could represent a future therapy of oral disease in CKD patients.