Background: The recently introduced 2017 World Workshop on the classification of periodontitis, incorporating stages and grades of disease, aims to link disease classification with approaches to prevention and treatment, as it describes not only disease severity and extent but also the degree of complexity and an individual's risk. There is, therefore, a need for evidence‐based clinical guidelines providing recommendations to treat periodontitis.Aim: The objective of the current project was to develop a S3 Level Clinical Practice Guideline (CPG) for the treatment of Stage I–III periodontitis.Material and Methods: This S3 CPG was developed under the auspices of the European Federation of Periodontology (EFP), following the methodological guidance of the Association of Scientific Medical Societies in Germany and the Grading of Recommendations Assessment, Development and Evaluation (GRADE). The rigorous and transparent process included synthesis of relevant research in 15 specifically commissioned systematic reviews, evaluation of the quality and strength of evidence, the formulation of specific recommendations and consensus, on those recommendations, by leading experts and a broad base of stakeholders.Results: The S3 CPG approaches the treatment of periodontitis (stages I, II and III) using a pre‐established stepwise approach to therapy that, depending on the disease stage, should be incremental, each including different interventions. Consensus was achieved on recommendations covering different interventions, aimed at (a) behavioural changes, supragingival biofilm, gingival inflammation and risk factor control; (b) supra‐ and sub‐gingival instrumentation, with and without adjunctive therapies; (c) different types of periodontal surgical interventions; and (d) the necessary supportive periodontal care to extend benefits over time.Conclusion: This S3 guideline informs clinical practice, health systems, policymakers and, indirectly, the public on the available and most effective modalities to treat periodontitis and to maintain a healthy dentition for a lifetime, according to the available evidence at the time of publication.

Background: The recently published Clinical Practice Guidelines (CPGs) for the treatment of stages I–IV periodontitis provided evidence‐based recommendations for treating periodontitis patients, defined according to the 2018 classification. Peri‐implant diseases were also re‐defined in the 2018 classification. It is well established that both peri‐implant mucositis and peri‐implantitis are highly prevalent. In addition, peri‐implantitis is particularly challenging to manage and is accompanied by significant morbidity.Aim: To develop an S3 level CPG for the prevention and treatment of peri‐implant diseases, focusing on the implementation of interdisciplinary approaches required to prevent the development of peri‐implant diseases or their recurrence, and to treat/rehabilitate patients with dental implants following the development of peri‐implant diseases.Materials and Methods: This S3 level CPG was developed by the European Federation of Periodontology, following methodological guidance from the Association of Scientific Medical Societies in Germany and the Grading of Recommendations Assessment, Development and Evaluation process. A rigorous and transparent process included synthesis of relevant research in 13 specifically commissioned systematic reviews, evaluation of the quality and strength of evidence, formulation of specific recommendations, and a structured consensus process involving leading experts and a broad base of stakeholders.Results: The S3 level CPG for the prevention and treatment of peri‐implant diseases culminated in the recommendation for implementation of various different interventions before, during and after implant placement/loading. Prevention of peri‐implant diseases should commence when dental implants are planned, surgically placed and prosthetically loaded. Once the implants are loaded and in function, a supportive peri‐implant care programme should be structured, including periodical assessment of peri‐implant tissue health. If peri‐implant mucositis or peri‐implantitis are detected, appropriate treatments for their management must be rendered.Conclusion: The present S3 level CPG informs clinical practice, health systems, policymakers and, indirectly, the public on the available and most effective modalities to maintain healthy peri‐implant tissues, and to manage peri‐implant diseases, according to the available evidence at the time of publication.

Evidence from epidemiologic studies suggests that periodontal infections are independently associated with subclinical and clinical atherosclerotic vascular disease. Although the strength of the reported associations is modest, the consistency of the data across diverse populations and a variety of exposure and outcome variables suggests that the findings are not spurious or attributable only to the effects of confounders. Analysis of limited data from interventional studies suggests that periodontal treatment generally results in favorable effects on subclinical markers of atherosclerosis, although such analysis also indicates considerable heterogeneity in responses. Experimental mechanistic in vitro and in vivo studies have established the plausibility of a link between periodontal infections and atherogenesis, and have identified biological pathways by which these effects may be mediated. However, the utilized models are mostly mono-infections of host cells by a limited number of ‘model’ periodontal pathogens, and therefore may not adequately portray human periodontitis as a polymicrobial, biofilm-mediated disease. Future research must identify in vivo pathways in humans that may (i) lead to periodontitis-induced atherogenesis, or (ii) result in treatment-induced reduction of atherosclerosis risk. Data from these studies will be essential for determining whether periodontal interventions have a role in the primary or secondary prevention of atherosclerosis.