TY JOUR TI COMPARATIVE ASSESSMENT OF EFFICIENCY ULTRASONIC AND SOUND METHODS OF ACTIVATION IRRIGATIONAL SOLUTION IN ROOT CHANNELS WITH SIMPLE AND DIFFICULT ANATOMY (PILOT STUDY) KW ultrasonic activation KW sound activation KW simple and difficult anatomy of root channels KW the combined activation method JO Actual problems in dentistry AU Sorokoumova, D.V. AU Griroriev, S.S. AU Lapteva, K.A. AU Shabalina, d.S. AU Kiseleva, D.V. AU Shagalov, E.S. AU Leonova, L.V. PY 2019 IS 15 PB TIRAZH Publishing House