Acute myeloid leukemias (AML) are a group of clinically and genetically heterogeneous diseases involving hyperplasia in the haematopoietic system. They are characterized by rapid clonal proliferation of cancer progenitor cells in the blood, bone marrow and other tissues, in addition to an anomalous production of normal cells. Initial signs of the disease tend to appear in the mouth, enabling a dentist to substantially contribute to a prompt diagnosis. This study presents a clinical picture of AML where oral lesions can be the first manifestation of the symptoms. The inflammation of the oral mucosa can be characterized by distinct primary lesions (related strictly to hematological disorders and leucocite infiltration), and secondary lesions (micro‑organic infection), or it can be a side effect of chemotherapy or allogeneic hematopoietic stem cell transplantation – allo‑HSCT. This paper describes oral mucositis caused by mucosal barrier injury (MBI), with the severity of the lesions measured on a five‑degree scale (according to WHO). The study also presents complications affecting the oral mucosa in patients undergoing allotransplantation, where Graft versus Host Disease may occur – a syndrome caused by the presence of the donor’s immuno‑competent cells within the recipient’s system. The treatment and prevention procedures for oral mucositis in patients with AML are also described in this paper.

Key words: acute myeloid leukemia, bone marrow transplantation, oral mucosa.