Endodontics Root Canal

In rare cases, root canal therapy fails to work as expected. The treated tooth might not heal properly or a patient might experience post-surgical complications that jeopardize the tooth. Root canal retreatment involves the removal of the previous crown and packing material, the cleansing of the root canals, and the re-packing and re-crowning of the tooth. In short, root canal retreatment is almost identical to the original procedure, aside from the structural removal. The success rate for a root canal retreatment runs at around 75%.

Root canal treatments and retreatments are a better alternative than extraction for most individuals. If a tooth has good bone support, a solid surface and healthy gums beneath it, it stands a good chance of being saved. Opting for root canal retreatment can be far less expensive than the alternatives. Dental implants, extensive bridgework and the creation of aesthetically pleasing prosthetic teeth cost far more than working with the natural tooth. They also require maintenance and feel less natural than a “real” tooth.

Why is root canal retreatment required?

Though the prospect of more endodontic surgery might not be pleasant, root canal retreatment is fairly simple. In general, the whole treatment can be completed in 1-3 visits.

There are a number of reasons why root canal therapy unexpectedly fails, including:

• Cracked crown leaking filling material.
• Curved or narrow canals not treated during the original procedure.
• Delay in the placement of restorative devices following the procedure.
• New decay to the tooth.
• New fracture in the treated tooth.
• Saliva entering the restorative structure.
• Undetected complex canal structures.

What does root canal retreatment involve?

On the day of the retreatment procedure a local anesthetic will be administered, unless another type of anesthetic has been selected. The affected tooth is isolated with a rubber dam. The dam protects the tooth during treatment from bacteria and saliva. The amount the dentist can do within a single appointment will much depend on the amount of inflammation present, and the complexity of the treatment.

The first step in a root canal retreatment is to gain access to the inner tooth. If a crown and post have been placed, these will be removed.

Next, filling material and obstructions that block the root canals will be removed. This removal is conducted using an ultrasonic handpiece. The advantage of using this tool is that any unwanted material is vibrated loose. Tiny instruments will then be used to clean and reshape the root canals. X-rays may be taken to ensure that the roots are thoroughly clean. If this part of the treatment proves to be complex, medicated packing material will be applied, and the rest of the cleansing procedure will be done at the next visit.

When the dentist is confident that the root canals are completely clean, gutta-percha is used to pack the space. This rubbery material seals the canals to prevent bacterial invasion. Finally, a temporary crown or filling is applied to tooth. At a later date, the color-matched permanent crown will be placed.

If you have any questions or concerns about root canal retreatment, please ask your dentist.

Cracked and fractured teeth are common dental problems. As people retain their natural teeth longer (due to advances in dental technology), the likelihood of cracked teeth increases. There are many reasons why teeth may crack, for example, biting on hard objects, trauma, grinding and clenching of teeth. All of these behaviors place the teeth under extra strain and render them more susceptible to cracking.

When tooth enamel is cracked, pain can become momentarily debilitating. In the absence of pressure on the crack, there may be no discomfort. However, as the cracked tooth performs a biting action, the crack widens. The pulp and inner workings of the tooth then become exposed, and painful irritation occurs. As pressure is released again, the two parts of the crack fuse back together, and pain subsides. If left untreated, the pulp becomes irreversibly damaged and constantly painful. The resulting pulp infection can affect the bone and soft tissue surrounding the tooth.

Symptoms of a cracked tooth may include:

• Unexplained pain when eating.
• Sensitivity to warm and cold foods.
• Pain with no obvious cause.
• Difficulty pinpointing the location of the pain.

What kind of cracks can affect the teeth?

There are many ways in which a tooth can be cracked. The specific type of crack will determine what type of treatment is viable. In cases where the crack is not too deep, root canal therapy can be performed, and the natural tooth can remain in the mouth. In other situations, the tooth is too badly damaged and requires extraction.

Here is a brief overview of some of the most common types of cracks:

Crazes – These are generally tiny vertical cracks that do not place the teeth in danger. These scratches on the surface of the teeth are considered by most dentists to be a normal part of the tooth anatomy. A craze rarely requires treatment for health reasons, but a wide variety of cosmetic treatments can be performed to reduce the negative aesthetic impact.

Oblique supragingival cracks – These cracks only affect the crown of the tooth and do not extend below the gum line. Usually, the affected part of the tooth will eventually break off. Little pain will result, because the tooth pulp (that contains the nerves and vessels) will remain unaffected.

Oblique subgingival cracks – These cracks extend beyond the gum line and often beyond where the jawbone begins. When a piece breaks off, it will usually remain attached until the dentist removes it. Oblique subgingival cracks are painful and may require a combination of periodontal surgery (to expose the crown) and endodontic treatment to place a crown or other restorative device.

Vertical furcation cracks – These cracks occur when the roots of the tooth separate. This type of crack almost always affects the nerve of the tooth. Because the tooth will not generally separate completely, root canal therapy and a crown can usually save the tooth.

Oblique root cracks – These cracks tend not to affect the surface of the tooth at all. In fact, the damage is only apparent below the gum line and usually below the jawbone. Root canal therapy may be possible, depending on how close the fracture is to the tooth surface. However, extraction is almost always the only option after sustaining this classification of fracture.

Vertical apical root cracks – These cracks occur at the apex (tip of the root). Though the tooth does not require extraction from a dental perspective, many patients request an extraction because of the high degree of pain. Root canal therapy alleviates the discomfort for a while, but most often, teeth affected by such cracks are eventually extracted.

How are cracks in the teeth treated?

There are many different types of cracked teeth. Some can only be exposed using X-ray machines, while others are clearly visible to the naked eye. In cases where the tooth root is affected, root canal therapy is the most viable treatment option. The pulp, nerves, and vessels of the tooth will be removed, and the resulting space will be filled with gutta-percha. A crown or filling will be added to stabilize the tooth, and it will continue to function as normal.

When the crack is too severe for the tooth to be saved, the dentist will perform an extraction. There are a number of restorative options in this case, such as bridges, dental implants and partial dentures. All of these structures can restore biting, chewing, and speaking functions.

If you have any questions or concerns about cracked teeth, please contact our office.