The authors present two patients from the out-patient department of their clinic where acute haemoblastosis was associated with pathological changes of tissues in the oral cavity. In the first case the clinical manifestation was acute myeloid leukaemia complicated by eruption of the lower third molars , in the second patient acute periodontitis and gingivitis with subsequent sequestering ostitits of the alveolar process of the mandible. In this context the authors draw attention to the possible use of systemic enzyme therapy in adjuvant treatment of this complication.

        Key words: acute haemoblastosis – manifestations in oral cavity