What are the three major forms of periodontitis identified by the 2017 classification?

The correct answer identifies the three major forms of periodontitis as set forth by the 2017 classification system established by the American Academy of Periodontology and the European Federation of Periodontology. These forms include periodontitis, necrotizing periodontitis, and periodontitis as a manifestation of systemic diseases.

The first type, periodontitis, encompasses a range of forms that can occur due to various factors impacting periodontal health. Necrotizing periodontitis refers to a severe form characterized by tissue necrosis and is associated with specific risk factors, such as immunocompromised conditions. Lastly, periodontitis as a manifestation of systemic disease highlights how certain systemic health issues can influence the development and progression of periodontal disease.

The other options do not align with the latest classification criteria. For instance, chronic periodontitis and aggressive periodontitis are not classified separately in the 2017 guidelines because they have been integrated into the broader classifications of periodontitis. Regenerative periodontitis is not recognized as a distinct form or type. Additionally, gingival disease and oral mucosal disease are not classified as forms of periodontitis. Thus, option A correctly encapsulates the major forms of periodontitis as outlined in the updated classification