Whether a crown with a post can be replaced would depend on the condition of the dental post and the tooth structure that it is bonded to.
Mild damage can be fixed via replacement but more severe damage may need alternative treatment. All of these conditions are variations of what can potentially happen to a tooth with a crown and post.
We will review when this type of dental prosthesis can be replaced and when it can’t. We’ll discuss what to expect for the procedure and also what the alternative options are if it can’t be replaced.
When it’s replaceable
A crown with a post can be replaced when only the crown falls off, only the crown is damaged, or there is mild tooth decay. A commonality among these conditions is that the underlying tooth structure remains relatively intact.
We will show you examples of what each condition looks like, how to tell if you have it, and why they can still be replaced.
Crown fell off
If the crown falls off without the post, meaning the post is still well bonded to the tooth, it can be replaced. Below is an example of how it may look along with a sample x-ray.
What it can look like:
- Inside of the crown may have residual cement but there is no post in it.
- Post is still securely cemented to the tooth.
- There is no decay present.
This condition can be replaced because the underlying tooth structure remains intact aside from the fallen off tooth cap.
- You may reglue the crown back on.
- Alternatively, if this situation keeps happening, you may need a new tooth cap.
Damaged crown
There are times where the crown with the post gets damaged. To be more explicit, we are referring to situations where only the cap gets damaged but the post in the tooth remains intact.
What it can look like:
- Tooth cap with pieces of the porcelain chipped off.
- Crown that is cracked in half.
- A hole through the cap.
- The tooth with post remains otherwise intact.
Since this situation is defined by a defective crown, the proper treatment would be to replace it with a new undamaged cap for your tooth.
Small cavity
Teeth with a post and crown are not immune to tooth decay, which means that it can still get a cavity. This can happen if you don’t take care of it such as forgetting to brush it or if you eat too many sweets.
What it can look like:
- Decay by the gum line where the gap between the crown and gums are.
- Black or brown discoloration by the crown margin.
- Soft tooth structure.
Treatment for a small cavity on a crown post tooth would require decay excavation. Then it can be restored with a core build up and a new tooth cap.
- The damaged tooth structure can be fixed with core material.
- However, the crown will no longer fit so you will need a new one.
When it’s not replaceable
A crown with a post can’t be replaced when the post breaks, the crown falls off with post attached, or the presence of severe tooth decay. All of these conditions are relatively catastrophic in nature.
We will show you examples of what each condition looks like, how to tell if you have it, and why they can no longer be replaced.
Broken post
This condition is when the crown falls off but the post is snapped in half. Essentially part of the post is still lodged into the tooth while the other part is stuck inside of the cap.
What it can look like:
- Crown has part of the post in it.
- Tooth has part of the post in it.
Prognosis for replacing this is questionable to poor. We recommend a more predictable restorative option such as extracting the remaining tooth. After that you can think about replacing the missing tooth with either an implant or dental bridge.
Fallen off crown with post attached
A crown that fell off with the post attached is typically non-restorable and non-replaceable. This isn’t just the glue loosening because it is actually a tooth fracture.
What it can look like:
- Fallen off crown with post still stuck inside of it.
- Tooth is now missing a post and you can see into the root canal.
- Pieces of natural tooth structure also embedded into the cap.
Recommended treatment for all tooth fractures would be an extraction. Missing tooth replacement option would be either a bridge or dental implant.
Large cavity
Depending on the extent of the decay, you may or may not have enough tooth structure left to redo the crown and post. That is why we made the distinction between a small cavity and a large one.
The decay will usually come in through the gap or crevice between the crown margin and your natural tooth structure. While porcelain can’t get cavities, the natural tooth at the junction still can.
What it can look like:
- Black or black color near crown margin.
- Affected tooth structure looks soft and mushy.
For very large cavities affecting a crown with a post, it is typically non-restorable. That means it is not recommended to attempt replacing it with the same exact treatment. Once again, we recommend an extraction with an implant or bridge.
Replacement procedure
Replacement for a crown with a post has the best prognosis if only the crown needs to be replaced. Typically if the post needs to be replaced as well, the prognosis is not as good. However, it can be done if the post wasn’t completed in an ideal fashion the first time.
What to expect when replacing just the crown:
- Administer local anesthesia.
- Cut the crown off by drilling.
- Prepare the tooth and remove all decay.
- Pack cord to push the gums away for an accurate impression.
- Take a triple tray impression of the teeth.
- Fabricate temporary crown and cement it temporarily.
- Clean off residual cement.
- Choose a tooth color for the new cap.
The image above shows what needs to be done for the crowns in order to remove them and replace them. Usually a slit is drilled from one end of the cap to the other and then it can be wedged off.
What to expect when replacing post and crown together:
- Administer local anesthetic.
- Remove old crown and post via drilling.
- Prepare a deeper post space into the canal with gates glidden and peeso reamers for better retention.
- Cement in a longer prefabricated post and build up the core.
- Prepare the tooth for a crown.
- Pack a cord around the gums for an accurate impression.
- Take an impression of the teeth.
- Fabricate a temporary crown and temporarily glue it.
- Clean off residual cement.
- Choose a tooth color for the new cap.
In summary, the replacement process is very similar to the first time that you had the procedure done. The only difference is that the old crown and post needs to be removed prior to placing a new one.
How many times can it be replaced?
Our estimate is that you can probably replace the crown and post two to three times at most. There is a limit to how many times you can replace a crown with a post because every time you drill into the tooth, it loses natural tooth structure.
The less of your tooth you have left, the less retention the cap with post will have. What that ultimately means for you is a crown that keeps falling off.
Alternative to replacement
If the tooth cap with a post can no longer be replaced with another one, the next option is to extract the whole tooth. From there, you will need to consider what to replace your missing tooth which can be either an implant or a bridge.
Alternate treatment options:
- Tooth extraction. Surgically remove the tooth with the cap and post. Once this procedure is completed you will have a hole in your jaw with a missing tooth.
- Dental bridge. A minimum of three connected crowns that are used to replace a single missing tooth. It does require shaving the adjacent two teeths.
- Dental implant. A more conservative way to replace a missing tooth since it does not require shaving adjacent teeth. A single titanium screw is implanted into the jaw bone to replace a single tooth.
Verdict
Yes, a crown with a post can be replaced but only if it isn’t damaged beyond repair. In other words it depends on the condition of why it needs replacement and the severity of it.