Case of abscess in a pregnant woman is very interesting because of the risks and difficulty in handling. Patient 25 years old, female, married. 35 weeks pregnant. Consultation with that frame of 15 days to develop: sore molar on the right side, went to see dentist and gynecologist, who will prescribe paracetamol, with no improvement, by which aggregate 5 days later with no results prednisone and Ceftriaxone positive. 72 hours before the query are added to the table right masseter area of swelling, and difficulty in mouth opening. On physical examination draws attention in a region BOMBMENT right masseter. For it turns out oroscopy Trimo grade III, dentures in poor condition. Coated tongue is not observed drainage of pus by the mouth, pain to percussion of the second and third molars rights. Blood cell count 11,100 white blood cells are found with 78% neutrophil. PREVIOUS consultation with the Department of Gynecology begins antibiotic treatment with amoxicillin sulbactam, 45 g / day and dexamethasone 34 mg / day. Takes place with surgical drainage that shows good development. Three weeks after the patient has uncomplicated delivery.