Periodontal diagnosis in the context of the 2017 classification system of periodontal diseases and conditions: presentation of a patient with periodontitis localised to the molar teeth.

The objective of this case report is to illustrate the diagnosis and classification of periodontitis, according to the 2017 classification system, as recommended in the British Society of Periodontology (BSP) implementation plan. A 37-year-old female was diagnosed with periodontitis (molar-incisor pattern), stage III, grade C, currently unstable. Several issues pertinent to the diagnosis of localised forms of periodontitis in young patients are discussed in relation to the current and previous classification systems. Periodontitis can be limited to a few sites and this case highlights the importance of the careful application of the basic periodontal examination (BPE).