You are here:

Dentistry/post& core vs just crown


QUESTION: My son is just 21yrs and when he was younger around 14 or so he required a root canal and another one when he was around 17. The root canal was then closed with a normal filling I think and there were no complications. Now we would like to have a more permanent 'finish' especially as he will be going away to study. In any case the fact that a crown would eventually be needed was explained when he had the root canals.
Our dentist has now explained that there are two options 1. post and core and the a crown 2. just a crown by itself (steel with porcelain)and that option 1. is better because it makes the tooth stronger. however I feel a crown by itself might be better. What is your opinion. Thank you so much. Polly

ANSWER: Hi Polly,
    Like most things in life, this question does not have a simple answer. Much depends on factors that I could assess only by seeing your son. However, in general, dentists use far too many posts, and if it has a filling in it already, that will serve as a base. Posts do NOT strengthen teeth; they in fact weaken them. Your dentist needs to read up a bit. They are occasionally necessary when so much tooth structure has been destroyed that the base would fall out of the tooth without the additional retention of the post. Still, even in those cases, the post weakens the tooth because the dentist has to remove tooth structure to fit the post, because the post does not actually bond to the tooth as it would need to to strengthen it, and because it frequently looses and acts as a wedge, splitting the root. So, they should be used only when absolutely necessary. In my somewhat ascorbic opinion most dentists place them because it is an additional fee. Bottom line is that if your son has been doing fine for several years the tooth is obviously restored adequately, so if it is a posterior tooth (anteriors do not need crowns unless severely broken down), then it might benefit from a crown alone.

[an error occurred while processing this directive]---------- FOLLOW-UP ----------

QUESTION: Dear Dr liewehr,

Thank you so much for your time in answering my question. I am sorry I did not thank you earlier but for some reason your letter went to the junk section which I don't normally view.

Just to clarify, there are two teeth which have a root canal. Both are at the top on either side (second from the back). According to the dentist one has around 40% of natural tooth left and the other 30%. The rest of the tooth is filling. The teeth have been fine but we were told he would need crowns. The point is whether to have a post and core and crown or just a crown (should that also include a core?)

Thank you very much again for your time and this time I will respond quickly.


No worries, Polly. If they are the second from the back, and assuming that you have your wisdom teeth (a total of 16 teeth on top), then they would be your second molars, which we call "2" and "15". These teeth are more important, so worth keeping if possible. The "core" is simply a filling inside the tooth, so you probably have that already. All your dentist needs to do is to reduce the outside of the tooth by the thickness of the crown. The only reason a post is needed is to hold in the core, which is rarely needed. As we discussed, it weakens the tooth. So, to place a core would be simply to drill out your existing filling and replace it with another, usually unnecessary. I cannot see you unfortunately, so I am making some assumptions here, but it sounds like you simply need the crown. Any strengthening of the tooth is provided by the crown, not the post or core, which simply are used to hold the crown on.  


All Answers

Answers by Expert:

Ask Experts


Frederick R. Liewehr DDS, MS, FICD


I can answer your questions about root canal therapy in general. PLEASE DO NOT ask me to diagnose your particular problems or recommend treatment as I cannot do this without examining you and seeing your x-rays.


I am a Board-certified endodontist, former university department Chairman, teach dental residents, and have a private practice.


J of Endodontics, Endodontics and Dental Traumatology, O,O,O, Military Medicine, Medical Bulletin, J of Dental Education

DDS, MS (Oral Biology), certificate in Endodontics

Awards and Honors
Surgeon General's "A" Designator, Fellowship ICD, Order of Military Medical Merit

©2017 All rights reserved.

[an error occurred while processing this directive]