Odontogenic infection is an infection caused by a tooth. It most often occurs as a result of dental caries, tooth trauma, periodontal disease or pericoronitis. The penetration of microorganisms into the periapical tissue causes an inflammatory reaction that can be acute, subacute or chronic, depending on general and local factors. If the balance between the host's immune system and the degree of pathogenicity of bacteria is disturbed in favour of microorganisms, odontogenic infection starts spreading. The inflammatory process can spread from the periapical region, usually through the closer and thinner bone wall, perforate the periosteum, and reach the soft tissues. The localizations of the inflammatory process in the soft tissue and later routes of spread depend on the anatomical position of the muscles and fascia of the head and neck, so abscesses can occur intraorally or extraorally. They are clinically manifested by typical symptoms of infection (tumor, dolor, calor, rubor, functio laesa), due to the proximity of the masticatory muscles with less or more pronounced trismus and lymphadenopathy. In severe cases, after the establishment of anatomical communication between secondary spaces and distant regions, complications accompanied by general symptoms may occur. The treatment of odontogenic infection includes the removal of the cause, drainage of the purulent contents and the use of antibiotics, and the application of additional measures such as hydration of the body or analgesics, if necessary. Amoxicillin with clavulanic acid is empirically administered as an antibiotic, and if there is no improvement in the next two days, metronidazole is included in antimicrobial therapy.