What Can I Do About a Broken Drill Bit in My Tooth from a Root Canal?

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For most people, a root canal is an unpleasant experience. It doesn't have to be painful. But even a successful, smooth procedure isn't exactly fun. According to Dentistry.com, 90 per cent of root canals are successful and require no follow-up treatment.

But no procedure is perfect and ever medical intervention has risks. With a root canal, it is completely possible for a drill bit or file to break off and get caught in the tooth. The good side of the bad news is that because it happens frequently enough, there are ways to deal with this problem.

Root Canal

A root canal is a procedure in which a decaying or infected tooth can be salvaged by entering the tooth, cleaning out the pulp, sealing off the tooth cavity and then filling and crowning the tooth.

A dentist or endodontist--a dentist who specialises in problems inside the tooth--will start by numbing the patient. Usually, he or she will numb an entire side of the mouth, including the tongue. The dentist then drill into the tooth, opening it up.

Small, specially designed file instruments are used to enter and clean out each of the tooth's roots - eventually reaching the bottom and taking out the pulp. This essentially deadens the tooth, while leaving it intact.

Once all the roots are cleared and cleaned with antimicrobial solution, the dentist will close the tooth up with a filling, and then fashion a crown to restore the tooth's size and shape. In the end, the tooth should look like new. A successful procedure should end any further pain or infection.

Risks and Warnings

Before undertaking a root canal, a dentist should present the patient with an acknowledgement and authorisation to perform the procedure. It's important to read this document because it outlines the potential hazard and adverse effects. Usually these forms outline that it is possible for a dental instrument to break off during the procedure.

This is most likely to happen if the tooth has many or narrow roots which can be difficult to navigate. It can also happen if there is significant calcification on the inside of the tooth--especially the roots.


If a bit or a file breaks off during the root canal, the dentist will do a few things. First, he or she will try to remove it on the spot. If this isn't possible, the dentist will most likely complete the rest of the procedure on the unaffected roots so that all but the clogged one have been properly treated. This is important to preventing infection. If the dentist treated the root with antimicrobial solution before the instrument got stuck, then the chances of infection are minimised.

A general dentist will likely close up, put a temporary filling on the tooth and send the patient to an endodontist who specialises in these problems. The dentist will probably also put the patient on a course of antibiotics.


An endodontist will numb the patient and go back into the tooth. He or she may use some specialised tools to try to remove the lodged instrument. Endodontists also have some very small tools that may be able to get past the lodged bit.

If one of these small files can work around the bit, then the endodontist may be able to complete the procedure, leaving the bit in place. Once the canal is completely cleaned and the pulp removed, it may not matter that a foreign object remains.

While having a foreign object in the tooth always poses some risk of future infection, it is relatively low and normally the endodontist will close up the tooth with a temporary filling and send the patient back to his or her general dentist for a permanent filling and crown or restoration. Again, the patient will likely be put on a course of antibiotics.


If even the specialised tools fail, the pulp not removed or the canal not completely cleaned, then the endodontist may have to attempt an apicoectomy. This involves the endodontist cutting open the gum outside the affected tooth, removing some of the underlying bone so that he or she can enter the canal of tooth from the outside.

The endodontist will actually remove the end of the canal, remove any pulp, clean the part of the canal that was not previously reachable. Then he or she will seal up the end of the canal with artificial materials and close the gum.

Over time, the bone that was removed will usually grow back. The gum will be sutured and will heal. Much like with the other procedures, the patient will need to take antibiotics afterward. This procedure will also probably require post-surgical pain medication, as it is more invasive.