In 2008 I got my right side lower jaw wisdom tooth removed next tooth root canal was done in September this year severe pain started visited dentist he took an X-Ray & said infection in root canal as it was not properly done. Re-Root canal got done but again suddenly pain started Dr. advised to take Metrogyl 400 for 5 days pain stopped, cement filling was done & Cap was fixed but from second day pain again started I visited Dentist again he says will remove cap & filling keep it open with some cement in it for few months the infection will automatically go & then he will fill & fix the cap is this procedure correct? Please advice.