Comprehensive research conducted over the past decades has shown that there is a definite connection between periodontal and systemic conditions, leading to the development and consolidation of the “periodontal medicine” concept. The 2018 classification of periodontal conditions uses this concept as a key element of the precise diagnosis of and individualized therapeutical protocols for periodontitis patients. The topic of this review is the pathogenic connections that exist between periodontal disease and metabolic/digestive tract conditions. It is important to remember that the oral cavity is a key element of the digestive tract and that any conditions affecting its integrity and function (such as periodontitis or oral cancer) can have a significant impact on the metabolic and gastrointestinal status of a patient. Thus, significant diseases with links to metabolic or digestive disruptions were chosen for inclusion in the review, such as diabetes mellitus, hepatic conditions and gastric cancers. Periodontal pathogenic mechanisms share several significant elements with these conditions, including mutual pro-inflammatory mediators, bacterial elements and genetic predisposition. Consequently, periodontal screening should be recommended for affected patients, and conversely, periodontitis patients should be considered for careful monitoring of their metabolic and digestive status.

Periodontitis is characterized by low-grade inflammation of the periodontal tissues, the structures that support and connect the teeth to the maxilla and mandible. This inflammation is caused by the accumulation of subgingival bacterial biofilm and gradually leads to the extensive damage of these tissues and the consequent loss of teeth. Hepatitis B is a major global health concern; infection with the hepatitis B virus causes significant inflammation of the liver and the possibility of its gradual evolution to cirrhosis. Hepatitis D, caused by infection with the delta hepatitis virus, is manifest only in patients already infected with the type B virus in a simultaneous (co-infected) or superimposed (superinfected) manner. The dental and periodontal status of patients with hepatitis B/D could exhibit significant changes, increasing the risk of periodontitis onset. Moreover, the progression of liver changes in these patients could be linked to periodontitis; therefore, motivating good oral and periodontal health could result in the prevention and limitation of pathological effects. Given that both types of diseases have a significant inflammatory component, common pro-inflammatory mediators could drive and augment the local inflammation at both a periodontal and hepatic level. This suggests that integrated management of these patients should be proposed, as therapeutical means could deliver an improvement to both periodontal and hepatic statuses. The aim of this review is to gather existing information on the proposed subject and to organize significant data in order to improve scientific accuracy and comprehension on this topic while generating future perspectives for research.

Non-surgical periodontal therapy (NSPT) is the first essential step for the management of any periodontitis patient. This study aims to evaluate the impact of NSPT on pro-inflammatory mediators’ regulation and on clinical parameters in periodontitis patients who suffer from chronic hepatitis C. At baseline, selected patients were clinically evaluated for their periodontal status. A subsequent quantitative assessment of C-reactive protein and pentraxin-3 in samples of gingival fluid was performed by Enzyme-Linked Immunosorbent Assay (ELISA). Afterwards, NSPT was performed. Three months after NSPT, the clinical and ELISA assessments were repeated. The results show an improvement of the clinical parameters in periodontitis patients at the three-month recall. In chronic hepatitis C patients with periodontitis, the gingival fluid levels of pro-inflammatory markers reduced significantly. The targeted markers also expressed significant correlations with the clinical parameters used for the assessment of periodontitis’ severity. The results suggest that, while chronic hepatitis C patients exhibited a more negative periodontal status at baseline as compared to non-hepatitis ones, NSPT is effective in decreasing the local periodontal inflammatory reaction and in proving the periodontal status of this type of patients. Given the limitation of the study, periodontal screening and NSPT should be included in the integrated therapeutical approach of chronic hepatitis C patients, for its impact on the local inflammatory response.

The bacterial challenge on the periodontal tissues triggers an inflammatory reaction, driven by pro-inflammatory cytokines, that eventually leads to the periodontal structures’ damage. The pathogenic mechanisms of this inflammatory reaction are complex and are influenced by the type of host-immune response and certain local and systemic factors. These factors can influence periodontal inflammation, through the action of the various pro-inflammatory cytokines. Periodontal disease and certain systemic conditions can have a mutual association, as the pathogenic mechanisms of these diseases can involve similar molecular and cellular elements. The concept of ‘periodontal medicine’ comprises these pathogenic connections, focusing on the key role that periodontal health has on the general homeostasis and well-being.

Depression [major depressive disorder (MDD)] is a mood disturbance of multifactorial origin, associated with high rates of morbidity and mortality, lack of work productivity, adverse health behaviors, and increased healthcare expenses. MDD is a leading cause of suicide, and it affects the prognosis of chronic conditions (heart diseases, diabetes, and cancer, among others). Current pharmacological treatment for MDD covers different classes of drugs, including tricyclic antidepressants (TCAs), monoamine oxidase inhibitors (MAOIs), selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), and atypical antidepressants. The aim of this chapter is to review the literature, highlight the side effects of newer antidepressants, and especially point out the most important aspects of the latest agents approved for the treatment of MDD in adults: desvenlafaxine, levomilnacipran, vilazodone, and vortioxetine. Desvenlafaxine is a SNRI and the primary active metabolite of venlafaxine; also a SNRI, levomilnacipran is an enantiomer of the racemate milnacipran. Vilazodone and vortioxetine are multimodal antidepressants, which combine SSRI activity with additional receptor activity. Although they have proven efficacy in treating MDD and are being investigated for other possible indications, further detailed clinical trials are needed to establish their pharmaco-toxicological profile, following prolonged administration in patients who may suffer from various comorbidities.