Root canal therapy is the process by which the inflamed or infected pulp is removed from inside the root canals of a tooth. These tiny spaces are then disinfected and subsequently filled with a biocompatible filling material.
Signs of pulp damage to a tooth include consistent pain, prolonged sensitivity to hot and/or cold, swelling in the gum area, or discoloration of the tooth (typically after trauma). Sometimes there may be no symptoms at all; therefore, the presence of pain is not always the most consistent sign of whether a tooth needs root canal therapy.
The following is a broad summary of the steps involved when performing a root canal:
- Local anesthesia is administered to the tooth or region
- A dental dam is used to isolate the tooth.
- A small hole is made through the top of the tooth to gain access to the canal space.
- Using micro instruments, the pulp tissue is removed from the canal space.
- The area is thoroughly disinfected using antimicrobial solutions.
- The canal spaces are filled with a biocompatible filling material.
- A temporary covering is used to cover the access opening.
- Patients must follow up with their dentist for a permanent restoration of the tooth.
Most of the current studies in the dental literature report that root canal therapy has a 95-97% chance of success, if performed by a specialist (Endodontist). Occasionally, root canal therapy fails to completely heal a diseased tooth, due to factors such as recontamination. Often when this happens, another root canal treatment procedure (Endodontic Retreatment) is recommended in order to save the tooth. Endodontic retreatment is similar in technique to root canal therapy, but more challenging and time consuming.
Reasons for Retreatment
- Damage to the root: Root canal spaces can become infected as a result of a root fracture. Depending on the size and location of the crack, a retreatment procedure is recommended
- Contamination: When the root canal filling is exposed to bacteria as a result of decay or leakage of saliva, the treatment area may become infected again, and retreatment is recommended.
- Root canals are not thoroughly cleaned and sealed: For treatment to be effective, the root canals must be thoroughly cleaned and sealed as close to the tip of the root as possible. Failure to achieve this can increase the likelihood of the root canal spaces becoming infected and requiring retreatment.
Apicoectomy is a common surgical procedure performed by Endodontists, in order to treat a tooth that has persistent infection or inflammation, despite having had root canal therapy. This procedure is done under local anesthesia with no discomfort to the patient. The Endodontist retracts the gum tissue near the end of the root, in order to remove infected tissue.
The very end of the root is also removed and a therapeutic filling material is placed at the end of the root.
Most patients return to their normal activity the next day. Apicoectomy is the recommended treatment when non-surgical retreatment is not feasible.
Cracks in teeth are inevitable. They occur as a result of years of chewing forces, as well as potential clenching and grinding habits. Since the mouth is an environment which subjects teeth to constant pressure from chewing forces, cracks have the propensity to get deeper with time. As cracks get deeper into the tooth, patients start to experience pain to chewing. If the crack reaches the pulp of the tooth, root canal therapy is required, to ensure the tooth does not get infected. If a cracked tooth is not treated in a timely manner, the crack may propagate further down the root, causing a "split tooth", requiring extraction of the tooth.
Types of Tooth Fractures
- Craze lines: Commonly seen in adult patients, these cracks are on the outer enamel portion of the tooth only. They generally require no treatment, unless it is for esthetic purposes.
- Fractured Cusps: Due to repeated forces from chewing and/or clenching, the cusp (or "corner") of the tooth can crack. If untreated, the crack can eventually cause the cusp to break off. The treatment of choice is usually a crown restoration. If the fracture is deep enough, the pulp may become damaged and root canal treatment is necessary prior to having the crown work done.
- Cracked Tooth: This type of crack usually spans from the top (chewing surface) of the tooth and extends towards the root, and sometimes below the gum. The tooth will commonly require a crown to properly restore it to function. If the pulp is damaged as a result of the crack, then root canal treatment is required, prior to having the crown made. If a crack is deemed "too deep", restoring the tooth is not possible and extraction is recommended. An untreated crack can lead to split tooth.
- Split Tooth: If a cracked tooth isn't restored, it can propagate further down the root, resulting in a split tooth. The tooth feels "loose" due to it being split in two pieces. In most cases, a split tooth is not restorable and extraction of the tooth is recommended.
- Vertical Root Fractures: This fracture starts in the root and may extend laterally or upward towards the gum area. These fractures are commonly found in root canal treated teeth with a large post placed in the root. Patients may or may not exhibit any symptoms, and usually, a 3D image (CBCT) of the tooth, taken during the consultation appointment, can confirm a vertical root fracture.
- Horizontal Root Fractures: This type of fracture results from a severe blunt force to a tooth. A 3D image (CBCT), taken during a consultation appointment, will confirm the presence of a horizontal fracture. The tooth cannot be restored and extraction is recommended.
Teeth can sustain injuries as a result of trauma to the face. Examples include sports related injuries or a seemingly innocent incident where a front tooth sustains injury as a result of some sort of impact. Endodontists are highly trained specialists to manage most of these traumatic injuries. The types of traumatic injuries and the recommended treatments are listed below:
- Luxation Injuries: These injuries can dislodge the tooth out of its original position. The tooth will need to be realigned back into its original position and held in place with an orthodontic splint for a short term. In some cases, root canal treatment is required.
- Avulsed Tooth: Sometimes a traumatic incident can completely knock a tooth out of its socket. It is imperative to see a dentist within an hour of the accident to increase the chances of successful treatment. Gently rinse tooth, but do not scrub it. The tooth should be placed in a suitable storage medium in the interim. The ideal place is in the patient's mouth under the tongue, to ensure the tooth does not dry out. Other acceptable storage media are: contact lens solution and non-skim milk. The dentist will reinsert the tooth back into the socket and place a soft splint to hold in place. Root canal treatment is required within 7-10 days.
Damage to pulps of teeth in children at a young age may cause the root to seize its development into a mature root. This creates a root that has an open end. Apexogenesis and Apexification are procedures aimed at closing the root ends of these teeth. In Apexogenesis, a medicament is placed in order to "resuscitate" the pulp and allow it to continue to develop the root physiologically.
If the pulp of the tooth is completely dead and thus unable to be "resuscitated", apexification is performed. Apexification is a procedure which helps close the ends of the root artificially, using biocompatible materials and barriers.
Teeth can darken as a result of trauma. We can whiten a darkened tooth to match the rest of your teeth! The materials we use are highly effective at whitening the tooth from the inside. However, prior to the whitening, the tooth needs to have endodontic treatment done. Note, this type of whitening is completely different in technique than the traditional external whitening you may have seen advertised in dental offices or drug stores.