Margin decay is tooth decay that begins where the tooth meets the crown.  This is one of the hardest places for you to keep free of bacteria and plaque. 

Even though a gold crown, porcelain-fused-to-metal crown, or porcelain crown is bonded to your tooth is intended to protect a tooth, decay can still attack your tooth.  Margin decay is a serious problem with many people.  It is extremely important that we understand what margin decay is and that we detect it early on so something can be done about it.

Margin decay can occur or many reasons.  One reason may be that the crown simply does not cover enough of the tooth.  Bacteria are still sometimes able to enter through the margin of uncovered tooth surface at the bottom of the crown.  This is common when there is inadequate oral hygiene.  Bacteria cause gum inflammation, which then spreads to the tooth in the form of plaque and decay.   

The decay will continue to spread once it is under the surface of the dental crown.  Bacteria that have entered under the margin have full reign to spread over the remainder of the tooth.  The key to stopping this is to prevent it from occurring in the first place.  Not only do you need to faithfully brush your teeth, but you need to floss them as well.  .

Sometimes, too, margin decay sets in because the cement bond underneath the crown degrades and saliva leaks in.  This will quickly carry bacteria under the crown and allow plaque to grow on the tooth.  This becomes a challenging situation, because even dental x-rays cannot always see the decay.  

Margin decay must be treated immediately.  This is not one of those dental problems you can put off.  Doing so will result in runaway decay.    This decay will first penetrate the outer layer of the tooth enamel and eat away at the tooth dentin.  Then, bacteria will infect the dentin, which is far softer and more sensitive than tooth enamel.  After the decay completely moves through the dentin into the pulp chamber, it attacks the tooths root. 

At this point, a root canal will be needed to save the tooth, or the tooth itself will be completely lost.  Do not let this happen. 

People often ask us how, if it is so hard to detect margin decay, they can possibly know they suffer from it.

There are indicators that you can look for.  If your tooth feels sensitive, or if your crown feels lose, call us immediately for an appointment.  Otherwise, rely upon frequent, regular checkups and tooth cleanings. 

Dental crowns need to have professional checkups routinely performed because some things, like margin decay, can only be detected with a professional examination.

In most cases, we have to remove the crown to remove the decay from your tooth.  It is rare that we can preserve a crown after removing it, so we go ahead and make you a new one. 

On very rare occasions, we may be able to treat margin decay with a cosmetic dental filling, but this is the rare exception, not the rule.