Advanced diagnostic methods in periodontology focuses on the techniques used to measure the extent of periodontal diseases. The methods include a physical examination, microbiology and x-rays. Physical examinations compare the bleeding on probing with bleeding on marginal probing, and the WHO-621 probe is also explained. For microbiology real time PCR, metalloproteinases and volatile sulphur compounds were studied. X-rays included panoramic, periapical, cone beam computed tomography (CBCT) and magnetic resonance imaging (MRI) evaluations.