At Jerusalem Dental Clinic, root canal retreatment is one of the solutions for problems that develop in a tooth that has already had a root canal. When a previous root canal fails or a new infection develops, Dr Haim Aseriel and the clinic team assess the case and propose the appropriate treatment. A failed root canal often brings pain and worry, so explanations and pace are adapted to each patient, in English.
For sudden pain or a suspected new infection around an old root canal, you can ask for an urgent appointment with an emergency dentist: the clinic sees urgent cases the same day during opening hours, on the same phone number. The clinic is closed on Saturdays and at night, when urgent cases go to a hospital emergency room; fever, swelling that spreads toward the eye or neck, or difficulty swallowing or breathing require going to the emergency room immediately. Detecting a problem early may prevent further complications and improve the chances that retreatment succeeds. Diagnosis relies on X-rays and, when needed, on 3D imaging (CBCT) taken at the clinic to find the source of the problem and plan treatment.
Treatment starts with a consultation: reviewing your medical history, examining the tooth and presenting the options, including retreatment and its alternatives, so that you can make an informed decision.
What is endodontic retreatment, and why consider it?
Endodontic retreatment treats a returning infection or problems that developed after an earlier root canal treatment. Unlike a first root canal, it requires removing the previous filling materials, thoroughly cleaning the canals and dealing with problems that were missed or left untreated the first time.
According to the AAE, the reasons a root canal fails include:
- narrow or curved canals that were not treated during the original procedure
- complex canal anatomy that went undetected the first time
- a delay in placing the crown or permanent restoration
- a restoration that did not keep saliva out of the tooth
- new decay, a loose or cracked crown or filling, or a cracked tooth
Retreatment can keep the natural tooth and avoid an extraction and an implant. Although it is more complex than a first root canal, it is in many cases a better alternative to extraction. Keeping the natural tooth prevents neighboring teeth from drifting and the bite from changing, which can happen after a tooth is lost.
In a systematic review of secondary root canal treatment, about 77% of retreated teeth were judged a success (Ng YL et al., 2008). The approach is conservative: the examination assesses the tooth and proposes a suitable treatment, with a clear explanation of the chances of success and the risks.
How is root canal retreatment done?
Retreatment follows structured steps adapted to each case. First, the dentist assesses the tooth with X-rays and a clinical examination.
After diagnosis, the treatment itself, done under local anesthesia, includes several main steps:
- removing the existing restoration (crown, filling) to reach the root canals
- removing the previous filling materials from the canals
- finding and treating canals that were missed the first time
- thoroughly cleaning the canal system and removing infected tissue
- sealing the canals again
- placing a temporary restoration until the permanent one is completed
In particularly complex cases, a surgical procedure called an apicoectomy may be needed. A small incision is made in the gum, the infected root tip is removed, and the end of the root is sealed with a biocompatible material. It may be necessary when the root tip cannot be reached through the tooth itself.
After retreatment, the permanent restoration should be placed as soon as possible. Depending on how damaged the tooth is, it may be a filling, a crown or a core with a post to reinforce the tooth. A suitable restoration seals the tooth against bacteria and gives it the strength it needs.
When is retreatment of a root canal not the right choice?
Despite its advantages, retreatment is not always the right solution. The aim is a treatment with reasonable chances of success and a real long-term benefit. Sometimes extracting the tooth and replacing it with an implant or a bridge is the better option, medically and financially.
Root canal retreatment is usually not recommended for:
- a tooth with a deep root fracture or extensive vertical cracks
- significant loss of supporting bone from advanced gum disease
- a tooth that has had several unsuccessful retreatments
- complex anatomy that does not allow full access to the canals
- a tooth with no role in chewing or appearance
The decision not to retreat is made after a thorough clinical assessment and together with the patient. All alternatives are then presented, including dental implants, fixed bridges or removable partial dentures, with the advantages, drawbacks, duration and cost of each.
Examination, treatment plan and price quote
detailed and personalized
During the consultation, Dr Haim Aseriel examines your teeth, explains all the options and gives you a transparent price quote, with no obligation. The clinic is at 12 HaTnufa Street, Jerusalem.
When to see an endodontist for retreatment
In retreatment, the training and experience of the practitioner matter a great deal. According to the AAE, endodontists (root canal specialists) complete two or more years of additional training after dental school in the United States, focused on the pulp and root canals. They use dental operating microscopes to see the inside of the canals better and treat them thoroughly.
Complex cases
Endodontists deal with challenging situations such as complex canal anatomy, very curved roots, and blockages left by a previous treatment. They are also trained to detect hidden problems such as cracks, perforations of the root wall or unusual root shapes missed the first time. At the clinic, complex cases are treated by an endodontist who works there, when needed.
Disinfection and sealing
Whatever the tools used, thorough disinfection and a good seal of the canals are the key factors in preventing reinfection. Magnification, ultrasonic instruments and 3D imaging help, when needed, to find cracks, extra canals or unusual curves.
How do you know a root canal has failed?
A failed root canal is identified by a combination of symptoms and X-ray findings that point to a persistent or returning infection around the root. Common symptoms include pain when chewing, lasting tenderness to touch or pressure, and swelling or infection of the surrounding tissues. Sometimes a fistula (a point where pus drains) appears on the gum.
On imaging, the dentist may see a dark area at the root tip, a widened space around the root, or root resorption. Incomplete canal filling, untreated canals or a filling material that has broken down can also indicate that the original treatment failed. If the tooth also has a crown, see infection under a crown.
What to expect after root canal retreatment
Because retreatment is more complex than a first root canal, various reactions can occur afterwards. A common one is mild sensitivity or discomfort in the treated area, caused by the inflammatory response to treatment. According to the AAE, the tooth may be tender for a few days, but some patients have pain after a root canal that lasts longer.
Temporary tenderness when chewing is common, and the tooth may feel slightly "high" when you close your mouth; this should pass quickly. Mild gum swelling can occur and usually decreases within a few days.
3-5days
Most symptoms improve within this time (AAE)
Rarer effects include discoloration of the tooth, especially with some materials (such as MTA). Allergic reactions to the materials are very rare. According to the AAE, contact the dentist if severe pain or pressure lasts more than a few days, or if visible swelling appears inside or outside the mouth; fever or pus also need prompt attention.
Retreatment: diagnosis, disinfection and follow-up
Retreatment relies on clinical skill and careful planning adapted to the anatomy of the tooth.
Diagnosis with magnification and imaging
Magnification, ultrasonic instruments and 3D imaging help, when needed, to detect hidden problems such as cracks, extra canals or unusual curves that were not treated originally.
Disinfecting and sealing the canals
Disinfecting the canals with suitable rinses and sealing them again are the heart of the treatment. At the end, the tooth is restored with a crown or another suitable restoration to prevent reinfection and let it function over time.
Follow-up plan
After treatment you receive home-care and follow-up instructions. Regular check-ups track healing and confirm the success of the treatment over time.
Root canal retreatment cost and consultation
The consultation before retreatment identifies why the original treatment failed and builds a plan adapted to you.
The cost of endodontic retreatment is usually higher than that of a first root canal, because removing the old materials and re-treating every canal takes more time. It varies with the condition of the tooth and the challenges it presents; the factors are detailed on root canal cost. The consultation also covers the restoration after treatment, often a crown. You leave with a detailed written quote for the recommended plan, and receive itemized receipts that you can submit to your insurer (coverage depends on your policy).
The clinic is at 12 HaTnufa Street in Talpiot, south Jerusalem, open Sun 8:00–19:00 · Mon 9:00–19:00 · Tue–Wed 9:00–21:00 · Thu 8:30–21:00 · Fri 8:00–14:00. Consultations with Dr Haim Aseriel are held in English.
Root canal retreatment: frequently asked questions
Root canal retreatment, or endodontic retreatment, is a second root canal on a tooth that has already been treated, when the first treatment did not heal or a new infection has developed. Unlike a first root canal, it involves removing the previous filling materials, cleaning and disinfecting the canals again, and treating canals that were missed or not fully treated the first time.
A root canal can fail when narrow, curved or complex canals were not treated during the original procedure, when the permanent crown or filling was delayed or did not seal the tooth against saliva and bacteria, or when new decay, a cracked restoration or a fractured tooth exposed the canals to a new infection.
Root canal retreatment is done under local anesthesia, like a first root canal. It is usually longer and more complex, and may take more than one visit. Tenderness for a few days afterwards is common; according to the AAE, most symptoms improve within 3 to 5 days. Strong or worsening pain, swelling or fever should be reported to the dentist.
In a root canal retreatment, the dentist reopens a tooth that has already been treated: according to the American Association of Endodontists (AAE), the filling materials from the first procedure are removed and the tooth is checked for additional canals or new infection before the canals are cleaned, shaped and filled again. This makes retreatment more complex than a first root canal. In both cases the tooth is then restored with a permanent restoration, usually a crown.
When retreatment also fails, endodontic surgery such as an apicoectomy (removal of the root tip) can be considered, as it gives direct access to the lesion. If the tooth cannot be saved, the next option is extraction and replacement with a dental implant, a bridge or a removable denture.
Sources
- American Association of Endodontists, Endodontic Retreatment – View the page
- American Association of Endodontists, What's the difference between a dentist and an endodontist? – View the page
- American Association of Endodontists, Patient FAQs – View the page
- American Association of Endodontists, Root Canal Post Treatment Care – View the page
- Ng YL et al., International Endodontic Journal, 2008 – View the study
