Of all infections associated to oral pathology, the most relevant ones are those that are related to dental pathology. Cellulitis is an infection of the cellular adipose tissue located in the aponeurotic spaces. It can be classified on the basis of location, severity and evolution. The aponeurotic compartments that allow odontogenic infections to spread have been categorised as: superficial compartment, floor of the mouth, masticator compartment, parapharyngeal space, parotid space and paratonsillar space. The present work describes the anatomical structures that comprise these spaces. The clinical forms of facial cellulitis are divided into acute and chronic. Potential complications consist of orbital infections, necrotising fascitis, thrombosis of the cavernous sinus, cerebral abscess and mediastinitis. Diagnosis is made on the basis of anamnesis, physical examination and complementary procedures (analytical tests and imaging studies). Treatment includes: treatment of causes (depending on the underlying cause in each case), incision and drainage, antibiotic therapy (chosen empirically) and complementary medical care. Odontogenic infections are primarily treated with surgery and coadjuvant antibiotic therapy.