Expert: Howard Finnk, D.D.S., P.A., CEO - 11/8/2009

Question
Doctor, first let me provide some background info: Needed crown on #10 due to a failed bridge covering span 8-10. Tooth #10 had extensive decay and underwent root canal treatment(2 years ago) and a gold post was put in. #8 was loss to accident(more than 30 years ago)and #9 was extracted a year and a half ago(tooth not salvagable)also due to failed bridge.
 Had implants on #8 and #9 placed by an oral surgeon. General dentist restored implants with porcelain fused to metal(high noble) crowns a few months ago. Then a month ago, I've had an all-porcelain crown in #10, but had it removed by same dentist the next day because it felt too tight and painful. (The dentist agreed the crown on #10 wasn't a good fit and I wasn't billed for it.)
 I went to a different general dentist who suggested that since I have a PFM (high noble)for #8 and #9, it would look and feel best if I have the same for #10. Do you agree?
 The PFM (high noble) crown placed on #10 last week feels tight and there is a slight pain when I floss between it and when I eat on it (though overall, feels better than the all-porcelain.) By the way, I had no pain while wearing the plastic temporary which in fact felt very comfortable compared to the PFM crown and all-porcelain.
 What in your opinion do you think is causing the slight pain when I floss and when I eat on the #10 PFM crown? And what should I ask the dentist to do?
 Do you think a crown for a root canal treated tooth with gold post that is to be inserted near an implant restoration(#9)is more difficult or challenging for the general dentist and for the dental laboratory to get a precise fit? How can I ensure that the dentist and the dental laboratory are giving me a high quality crown?
 Curious to know if slight swelling and slight redness on gums (only noticed after crown was placed) is further proof that crown should be removed?
 Thanking you in advance,
 Tom
 P.S. Do you know how much minimum percentage of gold is needed to be classified as high noble? I've heard that high noble crowns never contain nickel. Is this a correct statement?  

Answer
Dear Tom:  To answer the easier questions first:  The standard for high noble metal requires that it has at least 40% gold content.  Another 20% must be a combination of platinum and/or palladium.  Usually an all porcelain crown is somewhat more difficult to fit properly.  Porcelain to metal is much more the standard for dentists today, and is somewhat easier to fit properly.

I do not know when this crown was placed, so I don't know the stage of healing that your gums are in.  I do not know if the bite on this crown is appropriate,  And I do not know if it fits well from a dentist's perspective.

A well-made temporary crown will usually feel better than a permanent crown because the temporary was made directly on your tooth, and the outside is made from an impression of your tooth.  This gives it a very accurate fit, and feels like your tooth.  A lab-made tooth is made on a model of your prepared tooth, which is made from an impression of your tooth.  And the lab technician usually does not have a model of your original tooth to copy.  He must make a mirroro image of the same tooth on the other side.  So, for the permanent crown, there are a number of steps from your original tooth to the final crown, each of which can lead to slight change from your natural tooth.  Meanwhile, your gum has gotten used to the temporary.  Now it is removed, and another crown is placed.  Usually the fit is good, but the edges of the permanent crown extend slightlyfurther under your gum than the edges of the temporary.  Your gum will adapt, and that adaptation takes several days to several weeks.  Stop using floss for several days, and stop chewing on this tooth for several days, and see if it does not begin to feel better.  If not, contact your dentist.  Good luck.  dd