Formaldehyde is used in the identification of clinical plaque in periodontal diseases. To prepare the mixture, 5 ml of 40% formalin, 20 ml of glycerin, and 100 ml of distilled water are mixed. The solution is applied with a small cotton swab REJA: 1.Formalin sinovi 2.Shiller-Pisarev usuli 3.Milk qonashining darajasini aniqlash 4.Qimirlash darajasini aniqlash 5.Kulajenko usuli 6.P.M.A ko`rsatkichini aniqlash 7.K.P.I ni aniqlash 8.Rentgenologik usullar 9.Xulosa