1. 1. Proceedings of the 2017 World Workshop on the Classification of Periodontal Diseases and Conditions and Peri-implantitiswww.perio.org;
2. 2. Dorri M. Periodontal diseases: New classification for periodontal diseases. BDJ, 2018,10.1038/sj.bdj.: 686-686.
3. 3. Clinical periodontology and dental implantation. Vol.1 (N.P. Lang, Ed, J. Linde; scientific editor, transla-tion by A.M. Panin.), M.: GEOTAR-Media, 2021, 720 p. (In Russian). doi:10.33029/9704-5673-6-PRDI-2021-1-720.
4. 4. Ovrutskiy G.D. Dental focus and its elimination. Kazan, 1990, 80 p. (In Russian).
5. 5. Kovyazina S.B., Latfullin I.A., Khitrov V.Yu. Tran-sient bacteremia. Kazan, 1998, 95 p. (In Russian).