A 44-year-old female patient has complaints of the face swelling at the right lower jaw area and teeth mobility. Objectively: soft tissues are without changes, the regional lymph nodes cannot be palpated. The alveolar process and the body of the lower jaw near the 46th, 47th and 48th teeth are thickened, painless when palpated, have bulges. The teeth in the thickened area are mobile. Puncture consists of brown fluid without cholesterol crystals. What is the provisional diagnosis?