A root canal tooth that broke off at the gum line often requires an extraction because it has a poor restorative prognosis. Afterwards, the missing tooth can be predictably replaced with either an implant or a dental bridge.
However, if you really want to save your cracked tooth, there are some creative options to keep that broken root canal tooth if your condition is eligible. You can try making a longer post/core, crown lengthening or even orthodontic extrusion.
Treatment options for a root canal tooth that has fractured off at gum line:
Extraction & implant
Extraction & bridge
Longer post and core
Crown lengthening
Orthodontic extrusion
We will discuss all of the pros and cons for each of these treatment options. There are certain situations where you can use them and also times where you shouldn't.
Extraction and implant
The most predictable restorative option for a root canal tooth broken off at the gum line is an extraction followed by an implant. The chances of saving the broken tooth is generally very poor so one of the best options is to remove it and replace with an implant.
What to expect: The entire process will take about 8-12 months from start to completion.
Most of the procedure time is spent waiting for the bone or implant to heal. In the meantime, you may want to consider getting a temporary flipper tooth while you're waiting for the permanent crown.
Pros:
Predictable results.
Long lasting (10+ years).
Fixed option, it stays in mouth.
Feels like your natural tooth.
Cons:
Most costly treatment option.
Takes a long time (8-12 months).
Need to wear a tooth flipper.
Prognosis: The current success rates for implants is about 95% over a 10 year horizon, which is very good. It does depend on the type of implant that is used but nonetheless, you can reasonably expect your new tooth to last a decently long time.
Extraction and bridge
An alternative to the implant option would be to extract the tooth and then get a dental bridge for your fractured root canal tooth.
This is less conservative than the implant because a bridge requires shaving down the two adjacent teeth. Nonetheless, it has served patients well for decades before the advent of implants.
What to expect: The whole process will take several visits and about 3-4 months for completion.
The good news is that you will have a temporary in the interim while you're waiting for the tooth socket and gums to heal before you make the permanent. The reason for the wait is that if you do it too soon, you may see gum recession on the crown margins after it finishes healing. That can result in a cosmetic issue.
Pros:
Feels like natural teeth.
Fixed replacement option.
Long lasting (10+ years).
Temporary bridge is much more pleasant than a flipper.
Cons:
Process may take 3-4 months.
Requires crowning the two adjacent teeth.
Can't use traditional floss to clean the bridge, requires floss threaders or superfloss.
Prognosis: A tooth bridge will serve you well because they can and do last for a very long time. The 10 year survival rate is roughly 84% which is very good. After all, they were the preferred tooth replacement option before implants. Patients definitely like them more than removable dentures.
Longer post and core
The least invasive restorative option for a root canal tooth that cracked down to the gum line would be having a longer post and core put in. Hopefully, the longer post will be able to help retain the crown by increasing it's retention. This option is akin to giving the cracked tooth a second chance with a redo.
What to expect: This treatment option will take several visits over the course of 4 weeks.
Visit #1 - Prepare the post space to have a cast post and core made.
Visit #2 - Cement the new post and prepare the tooth for a new crown.
Visit #3 - Permanently glue in the new crown.
Most of the waiting time for this procedure is the dental laboratory turnaround time for the cast post and the crown. It takes approximately 2 weeks in between each of the visits.
Pros:
Shortest treatment option (4 weeks).
Attempts to save the broken tooth.
The least expensive option.
Cons:
Depending on the severity of the fracture, prognosis may not be great.
Prognosis: This treatment option is basically a redo by making the post longer in hopes it can give the tooth a second chance. Sometimes it work while other times it fails within the next year or two but it depends on how severe the fracture was.
Crown lengthening
A common way to save root canal teeth that are broken off at the gum line is with a crown lengthening procedure.
Since there is no more tooth structure to put a new crown on, what this procedure does is shave away (reduce) bone to reveal more tooth structure for a crown to cement onto. You will often notice your tooth get longer looking which is why it is called crown lengthening.
What to expect: The entire process will take about 3-4 months to complete over several appointments. Most of the waiting period is waiting for the bone to recover after the crown lengthening which takes 8-12 weeks.
Pros:
Preserves your existing tooth structure.
Relatively quick treatment time 3-4 months.
Moderate cost (not the most expensive).
Cons:
May cause teeth sensitivity with the adjacent teeth due to bone removal.
Not recommended for front teeth.
Still requires new post/core and a brand new crown.
Prognosis: The longevity of this procedure is very good and can last you many years. The only downside is that you can't do this for front teeth that broke off at the gum line. If you crown lengthen front teeth, you will have a noticeable mismatch for the gingival margin when you smile.
Of course for posterior or back teeth, no one really notices this. Therefore this is only a valid treatment option for back molars and premolars.
Orthodontic extrusion
A non-traditional way to save root canal teeth that fractured off at the gum line is with orthodontic extrusion of the tooth root. This method uses braces to extrude (pull down) the fractured tooth to reveal more tooth structure.
The goal is similar to crown lengthening where you make the tooth longer so that it can retain a new crown.
What to expect: This treatment option will take the longest, often more than a year.
Pros:
Very conservative.
Saves your tooth by preserving it.
If it fails, you still have implant option.
Cons:
Costly due to need for braces.
Long treatment often taking longer than a year.
Prognosis: If this method works for you then that is great but personally we've never had a single patient opt for this proposal. People are often turned off by the additional braces cost and also the fact that it can take a year for it to finish. Most patients prefer shorter treatments to get a new tooth.
Which treatment is best for me?
Which treatment option you should choose for your broken root canal tooth that fractured down to the gum line would depend on its severity. For that you would need a consultation with your dentist to determine which ones have the best prognosis and go from there.
Of course finance also plays a large role into the decision making process as well. Nonetheless, in the opinion of our dentists in Long Island City, one of the best and most predictable restorative solution would be the extraction and implant. It is the preferred gold standard as of the moment.
