Why is restorative dentistry important?
Dental disease destroys tooth structure. Restorative dentistry is the
process of restoring function and appearance to these affected teeth!
The above picture (on the left) shows how dental disease can destroy the teeth.
The picture on the right shows how restorative dentistry can repair the damage.
How do we restore teeth?
The most well known way to restore damage to teeth is the basic filling.
Fillings are used to restore teeth when the damage to the tooth is minor.
When the damage is more significant and a lot of tooth structure needs to be replaced, dentists use restorations called inlays or onlays or crowns (sometimes called caps).
Sometimes teeth are missing - restoring these spaces is also possible with restorative dentistry.
Common ways to restore spaces are implants, fixed bridges, and partials.
White fillings (or "metal-free" fillings) are a great
esthetic way to restore teeth that have been affected by cavities.
At left is a before picture of some unsightly cavities that need to be
fixed. The picture below it shows what white fillings can do.
White fillings are made of "composite". Composite is essentially a
form of a plastic that is bonded into the teeth. The premise is
that teeth that have been weakened by cavities are re-strengthened by
the composite filling because the fact that the composite is bonded to
the tooth re-enforces the weakened structure. So white fillings
are more than just placeholders for holes in teeth ... they
give support to the teeth.
Another example of white fillings and their benefit is seen here ... first the cavities that weakened the teeth, and then the fillings that fixed the teeth.
What is a crown? And why would I need a crown?
A crown is a dental restoration used when teeth are extremely weakened from fractures, large cavities, large fillings, root canals, or cracks.
A crown is essentially a covering for the entire tooth in all dimensions ... the crown gives the tooth a protective outer layer that is made of gold, porcelain, or a combination of both.
Why is a crown needed?
One of the most common reasons crowns are recommended is for broken or fractured teeth. Sometimes fractures can be repaired with fillings, but many times there is not enough healthy tooth to support a big filling so a crown gives the tooth a better prognosis.
Also - large fillings are sometimes culprits with tooth fractures. If the tooth is over-stressed because of a large filling, it can develop crack lines.
If this is the case, then when a fracture or crack is diagnosed, a crown is sometimes recommended because replacing a large filling with a larger filling will inevitably stress the tooth more and cause future problems. A crown is a preferable alternative in this situation.
Here are the situations where I feel a crown is indicated:
Cracked or fractured teeth
Replacing old large fillings that are "leaky"
Large cavities (where filling will be too big and potentially stressful to tooth)
Back teeth that have had a root canal (prone to fracture, more brittle when nerve is gone)
Existing crowns that are worn down, or have leaky edges or if cavities have formed beneath them
Examples of crowns and reasons for placement:
Silver fillings in back teeth replaced with porcelain crowns. In this case, the teeth needed crowns because crack lines were forming, the silver fillings were getting "leaky" at the edges, and the front tooth also had worn down on the biting surface.
Silver fillings replaced with a gold crown and a gold "inlay" (a large 'filling' made by a lab & cemented into place). The front tooth was showing crack lines (vulernable to fracture). The back filling had a cavity beneath it. The inlay provides more strength with less chance of fracture vs placing a very large traditional filling.
Should I replace my old crown?
This is something for each individual to decide. The dentist can offer an opinion, but ultimately it is a personal choice. Here are some examples of situations where individuals have opted to replace existing crowns.
The metal margin is showing on an old crown (or the root is showing on a front tooth). Newer materials are available now to combat this problem. Making front teeth with crowns look natural is a very real problem in dentistry.
With these examples, the old crowns are made of porcelain with a metal substructure. On the top pictures at left, the metal edge of this crown has darkened the gums. Replacing this crown with a newer material that does not have a metal substructure will eliminate the problem. The bottom picture is a similar problem with front crowns, but in this case, the root surface is also exposed. A new crown can be made to improve that situation.
Gum recession and sensitive tooth surfaces beneath crowns. These crowns protect the top portion of the tooth, but often the gum recedes below the edge of the crown. These crowns do not have to be replaced, but often times the patient elects to get new crowns for a couple reasons. (1) The new crowns are much more appealing visually with the root surface covered, and (2) the exposed root surface is now protected by the crown.
I am grinding my teeth down. What can I do? Will crowns help?
This situation is all too common in dentistry and is frustrating for patients. If this situation presents in my chair, it requires a very in depth and systematic treatment plan to remedy.
Crowns can certainly provide stability to dentition that is severely worn down. Often, it takes a considerable commitment on the patient's part to restore the mouth because multiple crowns can be required which means several visits. If there is clear communication between dentist and patient, this can be a very rewarding result for patients suffering from worn dentition.