The fact is that the subgingival calculus is very easy to miss if you don't use a special periodontal probe. With its help, you can reveal hidden subgingival dental sediments. If your dentist hasn't used it during preventive cleanings, there is a great chances you have periodontitis. Therefore, in our clinic, we always fill out an express index, which shows the presence or absence of subgingival calculus. We make the final diagnosis on the basis of a panoramic X-ray, examination of the oral cavity and filling in an expanded periodontal map.