Purpose: to compare the antimicrobial efficacy of chlorhexidine bigluconate used in different forms for the treatment of acute deep caries, to define the percentage of complications in the treatment of acute deep caries in children on the stage of its development in 6 and 12 months. Material and methods: Bacteriological study of demineralized dentin taken from the bottom of «the work space» by the sterile instrument, clinical monitoring of children after 6 and 12 months. Results. A significant reduction of colonies forming odontopathogenic and opportunistic microorganisms during the application of the film «Diplen» and a high percentage of favorable outcomes over the period of follow-up in the second study group. Conclusion. Qualitative etiological treatment conducted in a timely manner taking into account the structural features of hard and soft tissues of the tooth, creates the conditions for full formation of all tooth tissues.