What is Root Canal Infection? (4 Definitive Symptoms)


Last Updated on April 3, 2023 by Dr Gustavo Assatourians DDS

Taking care of the teeth is important to maintain a healthy pulp. If you don’t practice good dental hygiene, an accumulation of food debris (plaque) will cause dental caries. If they invade the pulp, it can result in a root canal infection.

Most oral diseases are treatable in their initial stages. The main ones are dental caries, periodontitis, and gingivitis, among others. According to published studies, dental disease affects more than 3,500 million people worldwide, with caries occurring most frequently in both adults and children. In the United States, they affect approximately 65% ​​of the adult population and 45% of children. To avoid dental diseases, it is necessary to know what structures make up the tooth, how they are affected, and in case of disease, how they should be treated.

How are the teeth made?

Teeth are hard anatomical organs located in the gums. They consist of the crown (the visible part of the tooth) and the root (the invisible part between the gums). Despite appearing to be a hard tissue, not everything is hard. The pulp in the central part is soft tissue composed mainly of nerve fibers that give the tooth sensitivity and vitality. Of note, the pulp is present throughout the tooth (both crown and root).


What are root canal infections?

Root infections are lesions caused by the presence of bacteria. Depending upon their location, they can be divided into intraradicular (inside the canal) or extraradicular (outside the canal) lesions.

They occur in both adults and children. In fact, in children this type of infection is frequent given the consumption of sugars in milk combined with poor oral hygiene. However, the management of this infection in children is handled differently than in adults. Since baby teeth will fall out in the future, they require cleaning the canals while not affecting the formation or the eruption of the permanent teeth.

In adults, the purpose of treatment is to keep the tooth in the mouth; and,since there will be no future replacement (as with temporary teeth), any materials used are maintained over time.


Dental can be divided into three categories:

  • Primary infection: caused by the colonization of bacteria, generally from caries. This infection initially destroys the tissues of the tooth, opening a cavity until it comes into contact with the dental pulp (canal).
  • Secondary Infection: mainly caused by organisms introduced during a professional intervention. Some sources of infection can be bacterial plaque, the presence of dental calculus, and caries in the crown of the tooth. However, an infection can stem from the contamination of endodontic instruments or by irrigation or canal cleaning systems.
  • Persistent infection: occurs due to the resistance of bacteria to the treatment carried out. Persistent infections are clinically indistinguishable, but they can cause various clinical problems such as fistulas or periodontitis.


Symptoms of root canal infection?

An infection could spread to the root through the canal of the affected tooth. Occasionally, it could erupt in an abscess, an inflamed area generally filled with whitish liquid pus that can cause discomfort in the neighboring tissues.

If the tooth itself is not inflamed, the inflammation is in the soft tissues that surround the tooth. The symptoms that occur in the presence of an abscess are:root-canal-infection

  1. Mild pain more annoying than painful
  2. Intense unbearable pain; the tooth may feel weak when biting or with mobility,
  3. Discharge of pus
  4. Sensation of heat in the affected area
  5. Sensitivity to touch or pressure.
  6. Change of color of the tooth (not always)

Whatever the case, the treatment to be carried out is a conventional root canal, called endodontics.


What is a root canal?

Endodontics or a root canal is a procedure that consists of the total or partial removal of the dental pulp, leaving the canal clean and free of bacteria to relieve pain caused by inflammation and preserve the tooth.

This treatment is one of the most performed by dentists in the world, it is performed under local anesthesia and can last several sessions.

Depending on the type of tooth, endodontics can be divided into

  • Uniradicular (incisors)
  • Biradicular (premolars) 
  • Multiradicular (molars)


What is endodontics for?

Root canal treatment is mainly used to relieve pain caused by an inflammation of the dental pulp. Generally, this inflammation is caused by an infection of the pulp, almost always due to extensive cavities. However, this is not the only cause, as the treatment can also be carried out for:

  • Fractures
  • Abrasion
  • Trauma
  • Wear


How is a root canal performed?

A root canal is a routine procedure that, although it takes several sessions, does not pose an inconvenience for the patient.

  • The first step is an exhaustive evaluation by the professional who examines the tooth both clinically and radiographically the number of roots and whether or not there is an infection that could compromise the neighboring tissues.

In the case of infection spreading to neighboring tissues, the patient will be prescribed an antibiotic and analgesic before performing the root canal, since when using instruments in the root, bacteria can migrate to the bone and gums.

  • Before starting the treatment, local anesthesia is applied to the affected tooth.root-canal-treatment
  • Once the tooth is anesthetized, pain and discomfort have passed. The dentist opens a cavity in the tooth with the help of rotary instruments. For some patients, the sound can be a bit annoying, but it is necessary since they expedite the work and shorten the treatment time.
  • With the pulp exposed, the infected tissue is removed with the help of tiny needle-like instruments, the canal is washed, cleaned, and dried. In some cases, the remaining cavity is filled with medication or temporary materials to help heal the infection or allow fluid to drain. These materials may be left in the canal for 2-3 days, then removed to ensure the tooth is completely clean. Then it is filled with a biocompatible material called gutta-percha.

Note: During the treatment, you may experience some sensitivity due to the instrumentation or the administration of the anesthetic. This type of symptomatology is transient and does not last more than a day. If it persists, the professional should be informed.

  • After completing the root canal, the tooth is restored with plastic or resin to return both aesthetics and functionality, although depending upon the compromised tooth structure, the tooth could be rehabilitated with a core and crown.

It is important to schedule control consultations with the specialist. Root canal treatment is a good treatment option, especially if the goal is to maintain the tooth, but if it is not controlled or properly cleaned, cavities may reoccur, affecting not only the pulp of the tooth but the neighboring tissues as well, resulting in the loss of the tooth in question.


How are root infections avoided?

Root infections can be prevented as follows:

1.   Adequate oral hygiene, at least three times a day with toothpaste, a toothbrush, dental floss, and mouthwash.

2.  Visiting the dentist at least twice a year. Professional dental cleanings help eliminate the accumulation of plaque and the development of diseases such as dental caries.


Contact us

If you have any questions about this or other topics, you can contact us at Channel Islands Family Dental as well as our page on Facebook. We look forward to your visit and we will make a timely diagnosis. Our dentists in  Oxnard, Santa Paula, Ventura, Newbury Park, and  Port Hueneme will be able to guide you toward the best treatment to take care of your health and give you back your best smile.



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