A 30-year-old woman came to the dentist with complaints of uncomfortable sensation of pressure in her upper right tooth, which aggravates in response to hot stimulus, and foul smell from the mouth. Objectively: there is a deep carious cavity in the 17 tooth, which communicates with the tooth cavity. Deep probing causes severe pain, percussion of the 17 tooth is painful. X-ray: there is slight widening of the periodontal ?ssure near the root apex. Electric pulp test - 70 microamperes. What ?nal diagnosis can be made?