Clinical picture, bacterial passage, and immune status were studied in patients with chronic traumatic and chronic odontogenic mandibular osteomyelitis. The deepest disorders of biocenosis and the highest incidence of immunodeficiencies were observed in patients with chronic odontogenic osteomyelitis. Local and total ozone therapy is suggested for antibacterial and immunomodulating treatment. Medical ozone exposure promoted more complete and rapid normalization of nonspecific resistance and T-cellular immunity, thus accelerating clinical cure and reducing the incidence of complications.