Odontogenic infections usually respond well to outpatient care; however, these can be very complicated and demand hospitalization. The aim of this study was to assess retrospectively the characteristics and medical management of patients needing hospitalization for the treatment of odontogenic infections. The personal data, symptoms presented, and therapeutic procedures adopted were analyzed. The predominant age group was from 0 to 10 years (30%), and a sex relation of 1:1 was found, but there was no significant difference (P = 0.337). The most frequent diagnosis was of dentoalveolar abscess (86.3%). Pain (47.1%) was the prevailing reason for hospitalization, with pulpal necrosis (67.5%) as the main cause. There was a prevalence of involvement of the lower permanent teeth (41.4%) and lower deciduous teeth (23%). The prevalent clinical aspect was submandibular or facial swelling (61.4%). The most administered antibiotic was penicillin G associated with metronidazole (25.3%). Most cases (58.7%) presented regression with antibiotic therapy, and in some cases, surgical drainage was necessary (18.7%). One case of Ludwig angina resulted in death. The mean length of hospital stay was 4.4 days, being higher in the cases of Ludwig angina. It was concluded that most cases of odontogenic infections requiring hospitalization were of dentoalveolar abscess occurring in young people of both sexes, associated to the lower permanent molar teeth, presenting with swelling, with regression of the symptoms after antibiotic therapy and hospitalization for some days, with some of the cases requiring drainage.