Onlay vs. Crown? Which is best?

[vani403]

I recently had a cavity removed from a molar.  Because it was quite deep, the dentist filled it with a sedative filling and we waited two weeks to see if I experienced any sensitivity.  During that time I did not have any sensitivity to cold or hot and the tooth felt fine.  Originally, I was told that the remaining tooth structure was about 2 to 3 mm away from the root and that if it did not become sensitive, the tooth would be restored with an onlay.  However, upon arriving to the appointment, he decided to do a crown.  When I asked why a crown instead of an onlay, I was told a crown would provide a longer lifetime to the restoration so I agreed.  If it helps to know the cavity was only affecting the MO surfaces.  My dilemma is that after more of the tooth structure was removed to prep for the crown, my tooth began to feel sensitive to the air device my dentist was using, when before it wasn't.  After the procedure was done I was feeling pain in my cheek (where the anesthesia was injected) and sensitivity in my tooth.  I had trouble sleeping due to the pain.  Today the tooth is no longer sensitive but I am paying close attention to it.  My question is, was there really a need to crown the tooth instead of using an onlay? Not sure if I chose wisely, since it seems the extra drilling might have caused root sensitivity.  If the tooth eventually needs a root canal, will I have to obtain a new crown? I guess I'm concerned about having a crown, then a root canal, and no metal-post to strengthen the tooth.

[Jerome Bogin, D.D.S.]

I can not give you an opinion of whether the inlay or crown was the appropriate restoration without seeing it. As far as the sensitivity that is not unusual after the tooth is preped for a crown.If you are so inclined you can have the crown temporarily cemented to make sure it is ok. If a root canal has to be done after the crown is permanently cemented the rct would have to be done through the crown.Not every tooth that has rct needs a post, but you will certainly be weakening the crown if the treatment is necessary after the crown is cemented.

[mike1105]

if you need a root canal, a post would also be placed, and ideally you should have a new crown. Crowning the tooth as opposed to onlaying the tooth is a judgement call, and depends on the amount of healthy tooth structure remaining. In some cases, an onlay preparation can involve MORE tooth preparation and drilling than a crown. Again, it all depends on the tooth and is a judgement call. Your symptoms post op sound normal--ie needle soreness and sensitivity.

[vani403]

Thank you both for your prompt response.  My tooth is already feeling better.  No where near as much sensitivity as yesterday.        I will definitely keep in mind not permanently cementing the crown right away.

[Bill8983]

A related discussion, inlay/onlay vs crown was started.