The crown placement (cementation) appointment may be possible without any numbing but it depends on the vitality status of your tooth. Is it still vital or is it non-vital? The answer to that will determine whether local anesthesia is necessary.
However for clarity, the crown placement appointment is the second part of a dental crown procedure.
Part I - crown preparation, impression, temporary crown fabrication, and sending out to dental lab for fabrication of permanent crown.
Part II - the tooth cap placement is when the permanent crown comes back from the lab and is ready to be glued in.
This article is NOT about the first part of the procedure which is when your dentist drills around the tooth and takes a mold of it. Today we are talking about the second visit which is when the final crown comes back from the lab and is ready for try-in and permanent cementation.
Vital tooth crown placement
If the tooth is vital, it will most likely need numbing because the nerves are still alive and they will feel everything that your dentist is doing. The entire appointment will feel extremely sensitive if you don't get any local anesthesia.
Before your appointment your tooth has a temporary crown on it and it most likely does not feel sensitive since the temporary is protecting it. However in order to try in the permanent crown, the temporary one will need to be removed.
It is when the temporary is removed that you will feel the sensitivity. The tooth nerves will become exposed once the temporary is off. Touching the tooth or even inhaling air will cause the tooth to feel discomfort.
During the try-in process your dentist will have to put the permanent one on and take it off quite a few times in order to adjust it.
When the permanent one is on the tooth it won't be sensitive.
When the permanent one gets taken off it will feel sensitive.
The constant bouts of sensitivity from removing it and placing it back on the tooth will make for an uncomfortable experience. For that reason, we highly recommend requesting numbing for the tooth so that you'll be comfortable for the entire procedure.
Non-vital tooth crown placement
If the tooth is non-vital, the crown placement appointment will NOT need any anesthesia at all. That's right, there will be no numbing for permanent crown placement. Since the tooth is dead, the nerves are consequently dead so it will not feel any sensitivity or pain at all.
Your dentist can try-in the crown and take it on and off as many times as they wish and you won't be bothered by it. It won't hurt at all since there are no nerves within the tooth to feel any pain.
Conditions with non-vital teeth:
After a root canal
Dead tooth
Root canal treated tooth
If the tooth already had a root canal, it would be unnecessary for any numbing during the crown placement visit. The endodontic procedure removes the entirety of the nerve from the tooth so it will no longer be able to sense any discomfort.
After a root canal, the tooth is considered dead since there are no more nerves and the tooth has no more sensations. Your dentist can fiddle around with the tooth as much as they want without it bothering you.
As a matter of fact, we never numb our patients for both parts of the crown procedure if the tooth had a root canal. That's evidence from our personal clinical experience.
Dead tooth
Aside from root canal treated teeth, a tooth can die from other causes such as trauma. The nerve in a traumatized tooth may take years before it is completely dead. However once it becomes a dead tooth, the nerves will no longer function nor will it be able to sense pain.
Dead teeth that need a crown placed on them will not require local anesthesia for the appointment. In fact, the crown preparation appointment with the bulk of the drilling didn't need any numbing either.
In case you were wondering why a dead tooth that doesn't hurt would need a crown, the reason is purely due to cosmetics. Once a tooth dies it will gradually start to discolor over the years. You'll notice it becoming more yellow or even grey looking once it has become non-vital. No one wants a grey looking tooth so patients will opt for a crown on it to mask the color.
Takeaway
Vital teeth will require numbing for the crown placement appointment since the nerves are still alive. Once you remove the temporary crown in order to fit the permanent one, the nerves will become exposed and feel extremely sensitive. For your own comfort, you should request to be numb.
Non-vital teeth on the other hand do not require any local anesthetic for the tooth cap placement. These teeth have non-functioning nerves so they will not feel any sensitivity nor discomfort.