A 32-year-old patient complains of the long-term dull toothache caused by hot food. The toothache appeared a month ago. Objectively: the 26 tooth has changed in colour, on the masticatory surface there is a deep carious cavity communicating with the tooth cavity. Superficial probing of pulp is painless, deep probing is painful. Electro-odontodiagnostics results: 85 /iA. What is the most likely diagnosis?