Tooth Abscess or Root Abscess – Infected Tooth

Definition of Root Abscess

A tooth abscess or root abscess is pus enclosed in the tissues of the jaw bone at the tip of an infected tooth. Usually the abscess originates from a bacterial infection that has accumulated in the soft pulp of the tooth. This is usually but not always associated with what is commonly described as a dull throbbing excruciating ache.

A root abscess typically originates from dead pulp tissue, usually caused by untreated tooth decay, cracked teeth or extensive periodontal disease. A failed root canal treatment, may also create a similar abscess.

There are two types of root abscess. A periapical abscess starts in the dental pulp and is most common in children. A periodontal abscess begins in the supporting bone and tissue structures of the teeth, and is the most common type in adults.

A root abscess usually occurs at the end of a root tip. However, it can sometimes be found along any of the root length and even at the top of the tooth where the roots divide. It is a small collection of dead tissue, live and dead cells. Any dental infection can seed bacteria throughout the body and cause other medical problems. It should always be treated as soon as possible. When the source of the irritation is removed, the dental infection goes away and the bone surrounding the tooth heals by filling in the damaged area with new bone.

Root Abscess Presentation / Symptoms

Common symptoms of an acute tooth abscess is a toothache or a persistent, throbbing pain at the site of the infection. Putting pressure or warmth on the tooth, can induce extreme pain.

In some cases, a root abscess may perforate bone and start draining into the surrounding tissues creating local facial swelling. The lymph glands in the neck in some cases will become swollen and tender in response to the infection.

Sometimes a root abscess shows up as a root canal complication after a root canal has been completed. In most cases, retreatment or root canal surgery successfully removes the root canal infection. In root canal surgery, a window is made through the bone and the dental abscess is cleaned out with special dental instruments. Bone is sometimes placed into the surgical area to assist with healing and the patient returns in about a week to have the stitches removed. Fortunately, this procedure is only necessary about one to two percent of all endodontic cases.

A toothache that is severe and continuous and results in gnawing or throbbing pain or sharp or shooting pain are common symptoms of an abscessed tooth. Other symptoms may include: fever; pain when chewing; sensitivity of the teeth to hot or cold; bitter taste in the mouth; bad breath; swollen neck glands; general discomfort, uneasiness, or ill feeling; redness and swelling of the gums; swollen area of the upper or lower jaw; an open, draining sore on the side of the gum.

If the root of the tooth dies as a result of infection, the toothache may stop. However, this doesn’t mean the infection has healed; the infection remains active and continues to spread and destroy tissue. Therefore, if you experience any of the above listed symptoms, it is important to see a dentist even if the pain subsides.

Treatment of Root Abscess

One treatment for an abscessed root is to extract it, thereby removing the source of infection. However, in select cases root canal therapy may be able save the tooth by cleaning the source of infection in the pulp chamber and root canal system.

Root Abscess Untreated Consequences

An untreated severe tooth abscess may become large enough to perforate bone and extend into the soft tissue. From there it follows the path of least resistance. Largely dependent on the location of the infected tooth; the thickness of bone, muscle and fascia attachments, the infection then spreads either internally or externally.

External drainage may begin as a boil which bursts allowing pus drainage from the abscess, intraorally (usually through the gum) or extra orally. Chronic drainage will allow an epithelial lining to form in this communication to form a pus draining canal (fistula). Sometimes this type of drainage will immediately relieve some of the painful symptoms associated with the pressure.

Internal drainage is of more concern as growing infection makes space within the tissues surrounding the infection. Severe complications requiring immediate hospitalisation include Ludwigs angina, which is a combination of growing infection and cellulitis which closes the airway space causing suffocation in extreme cases. Also infection can spread down the tissue spaces to the mediastinum which has significant consequences on the vital organs such as the heart. Another complication, usually from upper teeth, is a risk of septicaemia (infection of the blood), from connecting into blood vessels.

Depending on the severity of the infection, the sufferer may feel only mildly ill, or may in extreme cases require hospital care.

Prevention of Root Abscess

For prevention tooth abscess you should:

  • Have a good dental hygiene
  • Brushing teeth
  • Floss
  • Use antiseptic mouthwash
  • Make dental checkups
  • Make prompt treatment of tooth decay
  • Have low-sugar diet

Following good oral hygiene practices can reduce the risk of developing a tooth abscess. Also, if your teeth experience trauma (for example, become loosened or chipped), seek prompt dental attention.

  • Norman Hauptman



    I think saving the tooth is the best way. If you can do root canal or other dental procedure instead of tooth extraction and without bad aftereffects, do it.

  • Ksenija

    I’ve recently discovered I have a root abscess on a premolar (that has root canal and a crown). I am experiencing no symptoms but my dentist recommends extracting the tooth as she doesn’t think it can be saved. I am told this infection may have been there for years. I worry about the ways in which it may have affected my body even though there are no obvious sideeffects. The tooth is on my lower right side. Are there any serious side effects I could expect from this, even after I pull this tooth out?

  • http://dental jodie

    i was wondering if sombody could give me some advice i have had a tooth infection abcess for quite some time now nearly two years i am petrified of the dentist as i have a anxiety disorder but my tooth has been leaking puss now for around about two years i am dead ashamed of myself for letting this happen i have seen a dentist who said the tooth needed to come out. but i was to scared to have it out (my own fault) but he also said aslong as the puss is drainging which is a good thing then no seriouse complications would come of this just that i could give me great pain. but now recently form where i have been pushing my gum alot to relieve the puss i got a little timy hole in my gum. where you can see the bone tooth bone i think i need advice on any methods i could use to relieve my fright at the dentist

  • Have Answers

    I always get the nitrous oxide for any type of work.

    Good thing about this is I don’t care what they do to me after a couple of whiffs of nitrous oxide.

    If your dentist doesn’t use it… find one that does.

    I totally “know” how you feel & about the anxiety involved with any type of dental work… I get severe panic attacks & I am afraid I’ll pass out from the stress…

    nitrous oxide takes that all away.

  • Tarun Desai

    I have “root abcess” at root of upper left pre-molar teeth. I had root canal done and crown fitted on this about 5 years back.

    The root abcess hardly pains. I do feel a little sensation when I press my teeth. But not much.

    I showed to dentist and he recommended extraction. This is when I started studying if this was the only option. Would like to avoid extraction if possible.

    Things are a little complicated due to my having diabetes. My blood sugar level has gone up recently. My diabetes doctor says that often tooth infection increases blood sugar levels. I know that infections don’t heal easily when blood sugar level is high. Thus, I am stuck in a cyclic situation – tooth abcess increasing blood sugar and blood sugar slowing down treatment. Have now started insulin injections and have started on anti-biotics simultaneosly.

    The question I have, is there any hope to save on extraction.

    With Regards, Tarun Desai

  • Courtney

    I have a question, I went to the dentist and he told me that my tooth is infected, My gums are infected and that I have an infection in my jaw. I have been through 4 diffrent antibiotics, along with an anitbiotic injection. I still have pus draining from my gums and is extremly painful and tender when I bite down. The dentist told me not to eat anything I have to chew. My dentist also told me that he would pull it when the infection is gone, but none of the antibiotics seem to be working. What should I do? CONFUSED COURTNEY

  • Dr. Chetan


    The infection in tooth, gums and jaws collectively should have started from under the roots which would have spread into deeper areas and infection always leads to pus formation, which after pressure during eating, would drain the pus out.
    If the antibiotics given don’t work, then that’s probably because the infection has spread so much already, or the bacteria have developed resistance to it. If the antibiotics didn’t still work after at least 10 days time, then see a dentist.
    The next step would be drainage by incising the area, as it seems to be a severe infection that isn’t curable by drug usage. Pus drainage is common in infection, but if continued for long time, that should be checked off.

  • Ron


    Thank you for your recommendation in advance. I have a tooth which has had a root canal AND apicoectimy. About 6 months ago I began feeling warm/cold sensation in this tooth and later a fistula appeared. Extraction and implant has been recommended. The tooth looks GREAT not and I am not in pain. It is a little loose and occasionally a little sore, but looks nice. I would like to avoid getting this tooth extracted at all costs as the implant procedure is long and expensive and intrusive after many dental procedures I have been through and thought the worst was behind me.
    Please advise, I feel fine and see no reason to ditch a perfectly good crown for the long procedure of implant.
    thank you

  • Dr. Chetan


    Firstly, for the warm/cold sensation on the tooth, I suspect that’s not the same tooth which you had got the RCT done. Because, once the RCT is done, the tooth becomes non-vital as the pulp tissue is removed totally. So, do check once again whether you are able to localize the pain to that particular tooth or is it any other adjacent tooth?

    Also, although you got apicoectomy done, I guess there might be some infection around the apex which got larger and lead to the fistula formation.
    If the crown, and roots are still intact and good, you should visit a dentist and get it checked whether the apex got closed well after the treatment or not, and also whether the RCT was successfully done.

    If they are good enough, then there is no need of extracting the tooth.

  • Kathy Young

    I have had an infection of my front tooth (next to big one) for a long time. I was unaware because the dentist made a small hole in back of tooth for drainage and put a temp. filling until it was dry. The filling feel out so I replaced it, only to have severe pain and a huge soft spot form on roof of mouth. The dentisit cleaned out the tooth and it broke in the process. The root is still there, and I have been going every other day to clean it out until infection is gone. The dentist told me that the infection has formed a cyst at the apex and caused bone loss and she doesn’t know how long the crown and tooth will last and i may have to have surgery later on. My question is, is it worth it to do all of this for a tooth that is only the root and may require surgery later on, or should I just pull it and get a bridge? The teeth on both sides of this one have had root canal.

  • Adam W


    I have suffered for over a week with an abscess on my front tooth. ( A tooth which I have a veneer on from when I snapped it in half as a teen).
    First of all Amoxycillin was recommended, after 3 days nothing changed, then to A & E after face swelled and in agony. Then the Doctors gave Metronidozole and Tramodol.
    After a few days pain started to ease and the abscess burst and I squeezed then puss out…not as much as I expected.
    I then later that day felt loads better but was left with a super sensitive tooth to cold water and air.
    Ive been to dentist where he drilled into the tooth and drained any puss left, then had a filling to cover.
    Day after exactly same. Just today had same done again and dentist said used something in tooth canal to kill any nerve left.
    Still sensitive and now on Clindamycin.

    I f this doest work Ive been advised I may need either specialist RCT costing upto £1000 as I may have small lateral Root canals spouting off the dead main one apparently.

    Or the tooth pulling and a denture and bridge etc.

    Surely X-rays will show up these lateral root canals / nerves they suspect ?

    Or should I just wait for the stronger anti biotics to work, even though I have no swelling or pain anymore, just super sensitive !

    Please help, need a second opinion

  • Margaret

    I have been nursing an abscess tooth for a while. It is a premolar on the bottom right side. The abscess burst internally, I already contacted my dentist (they are closed fri-sun) and I can not get care until Monday. I have been saving up for a canal (Un-Insured) and I finally got enough cash when this thing burst. Most of the right side of my face and neck are semi-numb. Is there anything I can do through the weekend until I can see my dentist? Note: If i go to the ER or Urgent care I will not have enough money to get the canal done.

  • Laura

    The most important person to see is an endodontist/periodontist. This is a dental specialist. I had a tooth and nerve that had a very small crack that the dentist never notice by x-ray because he was not trained enough. I had all the symptoms of a tooth infection, yet even when it turned into a gum abscess and severe facial swelling, the dentist sent me to my doctor. The pain, swelling and infection became so severe that it triggered neuralgia in my trigeminal nerves and I was diagnosed with Trigeminal Neuralgia by my doctor (GP) but he could not figure out the swelling and thought said that it could be trigeminal neuralgia and something dental. I went back to my dentist and he refereed me to the endodontist/periodontist who discoverd the very slightly cracked tooth, the dead nerve, the infection, and the abcess. I am terrified of the dentist and never even had a cavity before…however the endodonist gave me meds to relax me and I have had the first part of my root canal. The facial pain and swelling has subsided and the abscess is draining, I go back in 2 weeks to complete the root canal and than after that my dentist will do a crown to cover up the dead tooth so no more bacteria can enter through the small crack…..SEE A DENTAL SPECIALIST!!! ENDODONTISTS RULE!!!

  • Isabelle Samet

    Thanks for some great articles , I will sure bookmark your site and come back on a regular base. Jjust got back from my 5th visit to the dentist this year. I’m not scared to go to the dentist, but I still get little anxiety attacks when I have to go. Nothing bad has ever happened and I love this dentist. He’s the best one I ever had. Today was my 6 month check up. My last one was in January. Then in April, I went back for a crown. So the first of those appointments was 90 minutes. It took forever to get that damn mold right. I kep gagging when it was put in my mouth. Then three weeks after that, I got the permanant one put on. To make my dental year even better, about a month and a half ago, a piece of my tooth broke off. It was around a filling and it didn’t go below the gum line, so my dentist fixed it by removing the old filling (the old sliver ones) and filling/shaping it with the composite stuff they use now. Which leads me to my 6 month check up today. He told me that I have a couple old silver fillings that are wearing away. So I get to go to the dentist a lovely half dozen times this year. The first old filling to be replaced will be done in October. I’m horribly glad I have dental insurance. I do have to pay a bit out of pocket, but at least it’s not the full price.

  • june brandon

    Have you ever heard of actinic cheilitis being caused from dental trauma or an ill-fitting denture? I had mega-problems with the replacement of a crown last spring resulting in infection with disease destroying the bone — front left top tooth. Now only option is to have tooth extracted with probable implant (rather than bridge). Also got a new ill-fitting denture in December at end of 2011.

  • James Clark

    James Clark, I am having problems with my dentist. My insurance is Medicaid and there are students working on my teeth with a licenced dentist watching over them. I have contacted both insurance company and dentist office. Needing to find out if my insurance will cover the crown. Both are giving me the-run-around. The insurance company is telling me to contact the dentist. The dentist office is telling me to contact my insurance company. Now before this I called the dentist office in the first place regarding a broken tooth to be looked at. The dentist would not repair the tooth without a crown. The tooth was fine before the assault. Mine you between the attack and the first repair it was about a year. As well as a root canal had been done on it also filling. It cracked as a result of the assault, because two days after being batteried the tooth cracks and then breaks. So another year past from the attack and this is when I get up to date with this new dentist that I am having problems with. Mine you its been a year from when my tooth had cracked. So it would decay in this short period of time being broke. This dentist said because of the decay it’s not from the attack. So keep in mine I have medicaid and there are only two dentist in my area that except Medicaid. Yes I did get a second opinion and this dentist said that there are three ways it could have happened: decay, fraggle from root-canal, or because of a blood-clot from root-canal. Why she is saying that in the x-ray a spot shows-up and their not sure what it is. After I said all of that, I tried getting help from the Crime Victims’ Unit and because of my dentist expert opinion did not think it was from the blow to the head and hitting the tree also falling on the sidewalk, being uncontious and having a seizure.
    The Crime Victims’ Unit could not help me. The director of the dentist office I attended too. Calls me all hostel, because I wanted information to bring to court about the pricing of the crown. Sense the asailent is responsible for my broken tooth. This is when I tell her to just send this information into my insurance company. She was rude to me, stating nothing in the report will change. Meaning the dentist’s expert opinion will not change. Which wasen’t necessary in the first place for her to give her advice. As if she didn’t want to send the correct information to my insurance company. This is how I end-up with contaction my insurance company again. They tell me to as my dentist and then dentist tells me to contact my insurance company. I am very frustrated, because there is no reason why I can’t get help with all this effort, too repair my tooth which isn’t my fault. Please help!!

  • vizor

    Hiya i had an imfection after tooth took out
    so went back and theh jusy gave me 3days of antibiotics amd put this brown seaweed stuff into it. does anyone have any idea wjat it is and if anyone had it done how long was it in for as i only got it done yesturday n its wanting to come out. im not eating or drinking proply n i still have a little pain. the area does look alot better tho so hopefully tmorro i will b alot better! but of anyone is in pain. just go back and dont be scared. they are there to help!

  • vicki

    I had a root canal performed 1996 on first molar left side, with a gold crown that covers the bottom to the back of tooth. There is a crack on the base of tooth where I chew. I have had an abscess for 6 or 7 years on the upper part of the gumline, looks like a swollen knot. It fills with pus off and on depending on what meats I eat. I noticed that after I had two crowns added next to the tooth, I begain to have problems. The dentist that I had at that time forced the crowns into the space, they were a little to wide to fit. My root canals have always had that extra nerve never located until after the canal was performed. I can’t afford to have the root canal redone or the crown, should I have my tooth pulled. I have already had my first molar on the bottom right pulled, not that I wanted too.I’m a 57 year old and afraid that my teeth will start spacing out soon.