Root Canal Failure

When a previously root canal treated tooth becomes re-infected, it is called root canal failure. The common causes of root canal failure are improper cleaning of the root canal, undetected root canal, inaccessible root canal, and root fracture. The treatment options of a re-infected tooth are doing a root canal again, apicoectomy, or extraction.

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Why did the infection spread to the jaw even after root canal treatment?

Query: Hi doctor, I had a root canal by a general dentist. I was told that the tooth was infected and going through with the procedure would be my best. I consented and had my treatment. I was done with the treatment and came home with full of instructions given to me. I had Penicillin and Ibuprofen for ev...  Read Full »


Dr. Tinu Thampy

Answer: Hello, Welcome to icliniq.com. As per the radiograph (attachment removed to protect patient identity), your tooth infection had extended beyond the root apex and entered the underlying bone, and it becomes a periapical abscess. The tooth roots are much flared also. Root canal treatment is a conserva...  Read Full »

Is it normal to have pain after root canal treatment?

Query: Hello doctor, I have pain two weeks after root canal treatment.  Read Full »


Dr. Mousam Chattopadhyay

Answer: Hello, Welcome to icliniq.com. I went through your query and the attached x-ray (attachment removed to protect patient identity). Kindly let me know how long you have been facing pain post root canal. Was it continuous after the procedure did, or it started recently? The x-ray does not s...  Read Full »

Why do I have pain in the tooth even after RCT?

Query: Hi doctor, Three weeks ago, I had a root canal done. But, the pain is still present. I cannot bite anything as the pressure gives pain. Kindly help.  Read Full »


Dr. Naveen Thomas

Answer: Hello, Welcome to icliniq.com. If even after three weeks of root canal treatment and the pain is not relieved, then you should show to the dentist as there may be some infection is remaining. Your dentist should take an x-ray again to check for infection and either repeat the procedure or give you m...  Read Full »

Can a tooth abscess cause light-headedness, dizziness, and a blocked ear?

Query: Hello doctor, I have a failed root canal with an abscess. I have been feeling light-headed, dizzy with a blocked ear. I had MRI and blood tests to rule out other issues, and they are clear. Can the abscess cause these issues? If so, how long for lightheadedness to go once the tooth is removed?  Read Full »


Dr. Ummah Mohammad

Answer: Hello, Welcome to icliniq.com. I would suggest you get the affected tooth extracted as soon as possible because it is not merely extraction, your dentist will first subside the collected abscess, and as soon as the treatment gets started, you will begin feeling better. Your question about if other...  Read Full »

Can unremoved files during RCT procedure cause severe tooth pain?

Query: Hello doctor, I had an RCT done on the lower molar (number 6) two months ago. The file was left inside the canal, which I did not know. It was a mild sensation for a month or so. Then I went for fixing the crown. The dentist asked to cut the gums because enough space was not there for fixing the cr...  Read Full »


Dr. Naveen Thomas

Answer: Hello, Welcome to icliniq.com. It may cause pain if the file is protruding out of the canal, but is not usually the cause. There may be a hidden canal infection. Usually, such pain is caused when more disinfectant liquid is injected into the bone beyond the canal. It should clear up when the l...  Read Full »

Why am I getting radiating pain on the root canal treated left upper tooth?

Query: Hi doctor, I am having severe pain on my left side jaw and cheek, frequently for about two years. It seems it radiates from the last tooth of upper jaw and lower jaw. Both are root canal treated and crowned. The pain radiates from those two to the left jaw, cheek, and inner ear. I have seen many de...  Read Full »


Dr. Naveen Thomas

Answer: Hello, Welcome to icliniq.com. You may have an abscess related to root canal treated teeth. As the pain is only on the left side of face, and near to those teeth, there might be a relation. Please attach your OPG (orthopantomogram), x-ray, and pictures of your jaw inside the mouth area where you h...  Read Full »

How to restore my tooth?

Query: Hi doctor, I have neglected my dental health for a long time. I am a 62 year old married male. I have had several teeth extracted. I lived with a couple teeth whose caps have broken off on my left side and a few molars on the right for chewing. I am suffering from hypertension and is controlled wit...  Read Full »


Dr. Naveen Thomas

Answer: Hi, Welcome to icliniq.com. By reading about your symptoms, it seems that your root canal treated tooth is the one causing the problem. The rate of success of such root canal treatment is lesser in old age and also if you are diabetic. The only meaningful solution seems to remove the teeth and place...  Read Full »

Why do I get pain in my lower tooth only while going to sleep?

Query: Hi doctor, I am having pain in my lower tooth whenever I go to sleep. Due to lockdown, I am unable to consult the dentist. Can you please tell me any tablet that I can use in the meantime.  Read Full »


Dr. Ummah Mohammad

Answer: Hello, Welcome to icliniq.com. Sorry for the pain you are bearing because of the prevailing situation. As you have already mentioned there is a cavity and when it reaches up to the pulp there develops an irreversible stage which generally is more painful during night time as we sleep. I think your t...  Read Full »

Why do I have pain after root canal treatment?

Query: Hi doctor, I had minor tooth pain before and got a composite filling. Then, I had extreme pain and opted for root canal treatment. I had a root canal before three days. I feel extreme pain and my tooth is still sensitive to cold. Is it possible that the nerve was not completely removed? Also, it h...  Read Full »


Dr. Geeth Sadasivam

Answer: Hi, Welcome to icliniq.com. Your doubt is partially right. The root canal treated tooth might get some entrapped bacteria, which causes you pain. It cannot be straight away told that the nerve was not completely removed. There are some reasons for postoperative pain. Improper shaping of the canal, ...  Read Full »

My root canal filling fell out. Please help.

Query: Hi doctor, I had a root canal and the filling fell off. I am too afraid of dentists. Hence, I did not go back to get a permanent filling. How bad can it be now? It has been a year. What to do?  Read Full »


Dr. Shwetha Hegde

Answer: Hi, Welcome to icliniq.com. Let me start by telling you that if you have been to the dentist and sat through the root canal procedure then getting a filling should be a cake walk. Without a filling covering a root canal filled tooth, either the root canal will fail or the tooth might just b...  Read Full »

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