Implementation of the new classification of periodontal diseases requires careful navigation of the new case definitions and organization of the diagnostic process along rationale and easily applicable algorithms. The aim of this report was to describe the rationale for one such approach designed for clinical practice and education.The authors developed empiric decision-making algorithms based on the new classification to effectively discriminate between the key periodontal diagnoses of periodontal health, gingivitis and periodontitis.A stepwise approach is proposed that includes (a) a sensitive screening step able to discriminate periodontal health, gingivitis and suspect periodontitis; (b) a specific confirmation step to provide differential diagnosis between periodontitis and the other conditions characterized by attachment loss; (c) a step to assess the severity and complexity of management of the periodontitis case (staging); and (d) a step to assess the risk profile of the case (grading). Specific decision-making algorithms are described for all steps of the diagnostic process.The proposed process allows discrimination between the different case definitions of periodontal health and disease. The diagnostic accuracy and cost-effectiveness of the process need to be validated in prospective trials generalizable to operators with different level of expertise, different populations and clinical settings.