A patient complains of limited mouth opening, pain during swallowing, fever up to 38,5°C, weakness, indisposition. Objectively: the mouth opens up to 1 cm. After Berchet anesthesia examination of the oral cavity revealed edema, hyperemia, tenderness of the pterygomandibular fold. Lateral and posterior pharyngeal walls are intact. The 38 tooth is semi-impacted. Palpation of the internal surface of the mandibular angle is painful. What is the most likely diagnosis?