What is a Dental Crown and Why Are We Getting One ?

            

(Photo: www.eastvillagedental.com   Dr. Jeffrey Krantz )

       I have been fairly lucky in my life from a dental standpoint.   I did have braces when a young teen. I had all of my wisdom teeth surgically extracted when fairly young.  I had the extraction of four secondary teeth and two baby teeth as a teen, because my orthodontist assured me that I had a very small mouth, and inadequate space for so many fairly large teeth.  I have had my share of dental fillings, particularly in back teeth.

              A dental filling, whether amalgam (the ones which are silver in appearance) or polymer (the ones that appear white after the filling) are still a time limited proposition.   A filling is a repair, and some of them last a great many years, but generally from the time a tooth is filled, there is an incomplete barrier, and decay can form in and around the filling itself and necessitate a periodic drilling and removal of that filling, or cause the need for a more drastic and expensive intervention. This is why we are told to report every six months, so that more conservative interventions can be taken before restoration becomes a more expensive and a more arduous task for all of us.

              I have always had a pretty strong gag reflex and I don't much enjoy anyone poking around in my mouth.  In my twenties,  I had three of my four biological children and therefore I spent 36 months or so, pregnant with them.  While I was pregnant, my gag reflex and salivation were in absolute overdrive.  In the second pregnancy I simply decided that dental care would have to wait until afterward.   This fact and the hyperemesis gravidarum I endured during the first pregnancy resulted in some damage and decay to my top molars closest to the back of my mouth. I remember the dentist saying, as if it were yesterday, "I have filled both of these with a deep sedative filling and I lined them with calcium hydroxide.  It will either work, or you will lose both of those teeth."   I was quite pleased when those teeth did not bother me, and successive dentists simply ignored them.  Twenty-five years later, one of them began to ache. It ultimately split and the only reasonable alternative became extraction.  The following Spring, the identical thing happened to the one on the other side. 

            Now, thirty years after those initial fillings, I am losing back teeth to extraction.   This week, one of my filled molars broke a small bit, and so I made an immediate dental appointment.  My dentist saw me Saturday.  I had hoped that she could simply fill the broken region as the original filling was still intact.  She told me that in order to save this tooth, she needed to place a crown over the tooth.  I remember paying for crowns for two of my sons, and the process didn't seem too bad.  Their molars seem perfect now.   My dentist now takes days off during the week when the fewest people turn up, but she comes in for four hours or so, on Saturdays and on Sundays if someone needs something.

          So I saw the dentist yesterday, and today I was the first patient as we began the process of my molar getting a crown.

This is an inside view of two crowns.  This photo came from http://mansfielddental.info/dental-crowns/

  This is an excellent website for information on the types of crown available today.

         What is a Crown ?        A crown is exactly as it sounds.  The damage or decay from a tooth is drilled away, and the surface is readied for a tooth to be fitted and "glued" over the peg which remains.   Usually, the initial crown is a temporary one while the permanent one is constructed using a dental impression which the dentist obtained during the initial crowning visit.  After the crown is intact, ALL of the tooth concerned is covered.   This is also done sometimes in order to preserve a tooth which has a large filling.   This is a fairly expensive procedure, and this might be why this was not offered to me when I started to have quite a few back teeth with larger and larger fillings, as the initial fillings aged and required drilling out and replacement.


What Material Is Used to Make a Crown ?      A crown can be made from a number of substances.  Sometimes a white polymer is used, particularly on a temporary crown.    Sometimes ceramic is used to formulate a permanent crown.   Sometimes gold is used.   Silver and palladium are also used.  Often, a dental crown consists of ceramic AND a precious metal of some kind.


How Long Does a Crown Last ?     Dentists quote that a crown will last ten years.  In reality, crowns can last as many as fifty years, or the remainder of the patient's lifespan.  Most dental insurances, if you have this, will pay for crown replacement after only five years. Of course, I have never had dental insurance, and so I pay for all of it.


       Things to remember about a crown.

1. They ARE costly, but they can result in a long term fix for the tooth in question.
2. Typically, there are at least two dental visits for such a procedure.
3. A fair amount of the tooth is removed in order to use dental cement to bond the crown to the remaining tooth.  Of course such removal is permanent.


         

Rendering from:  www.auburnfamilydental.com

                 The above rendering demonstrates that the original tooth is amended to a peg of a variety of shapes, and a customized tooth crown which today, normally covers the entire remaining peg is cemented in place.   In order to get a customized tooth, during the first visit and impression of your tooth, that side of your mouth or your entire mouth is taken.  Often a dental lab off premises constructs the customized crown for your dentist to affix later.