Dental Crowns in Missoula, MT
When teeth become broken down from decay, or a rogue popcorn kernel, they often need a crown. They can also need a crown if we are being proactive in defending against unpredictable breakage when your teeth are most susceptible (after a root canal or have developed certain cracks). We offer both tooth colored and conventional gold crowns. Either can be better in different circumstances. So what are the specifics on the different material types?
All Gold Crowns
This is one of the oldest, and arguably the best, crown materials. It's been around for many decades. My patients love these crowns for their durability (it's extremely rare they would break), for their smoothness, and for how little they will wear teeth that chew against them. The two disadvantages to gold are that it's not tooth colored (so my patients usually don't use them to fix front teeth) and as with much in life, you get what you pay for-- gold crowns are the most expensive option.
A sort of "offshoot" of a gold crown is the gold onlay. Sometimes an onlay can be used instead of a full crown in some situations to allow for a more conservative tooth preparation with less tooth reduction. In order for a crown to fit on a tooth, the tooth must be uniformly reduced. In order for the onlay to fit, the tooth is reduced in a non-uniform fashion. The margin, which is where the crown/onlay meets the tooth, is typically placed at or slightly below the gums with a crown.
With an onlay, the margin can be placed above the gums at many points. This makes it much easier to clean them when brushing, which is important since that margin is the most susceptible point on a crown to get a cavity. Typically, full crowns are done because they can be completed faster than onlays, and they're less technically demanding. However, many patients find the trade-off of more dental chair time to be worth preserving tooth structure as no synthetic material developed thus far is as good as a natural tooth.
PFM (Porcelain Fused to Metal)
PFM's have also been around for several decades, not quite as long as gold crowns, but still long enough to have a proven track record of success. The advantage that PFM's have over gold crowns is that the porcelain can be fused, or "bonded," to the metal/gold substructure so that the crown is white. This was a great development because now there was a crown that could be placed on front teeth and look natural. Everything has pro's and con's, PFM's are no different.
The downside to them is that the porcelain is very hard and brittle. Occasionally porcelain can chip or "un-bond" from the metal, thus exposing the metal (which is a silver color) and can be uncomfortable to your cheek or tongue. If it chips off in between teeth, food becomes lodged between the teeth, which doesn't feel good and can lead to cavities if not repaired in a timely manner. It's not common that the porcelain chips - when it does, it is often due to biting something hard unexpectedly (watch out for CornNuts!). Also since porcelain is hard, it wears the teeth it chews against.
Depending on the crown location, this wear can be minimal or it can be quite severe. Also depending on the location I can mitigate some of the wear by extending the metal/gold material to the portion of the crown that chews against the other tooth, so for this purpose, the crown acts like an all gold crown. These crowns generally cost less than the all gold crowns.
All Porcelain Crowns: Two Major Types
All-porcelain crowns are a relatively new player to the game. In the past, limitations with porcelain strength necessitated having metal/gold substructure to support it. Another issue was the first all-porcelain crowns looked really fake -- everyone could tell that it wasn't a real tooth. Thankfully, recent advances in technology have changed that. Within the last couple decades, there have been two new types of materials that show promising results for long-term crowns that fit well, are strong, and look just like real teeth: Lithium disilicate (eMax brand) and zirconia (Bruxzir brand).
This material is the newest type, in fact, it's still actively being developed to look more and more like a natural tooth. The molecular makeup of this material makes it relatively quite strong, but comes at the expense of translucency. The very first formulations developed were very opaque, think "bathroom sink." While it is unlikely that this material will ever be the most natural looking option, significant improvements have been made recently and many patients feel this is a fair trade-off for the price. Currently, this is the most affordable crown we offer.
Lithium Disilicate (eMax)
This material is one of the most natural looking crown material. Compared with the others, it's highly translucent, which mimics the enamel of a natural tooth. The compromise is that it is one of the weaker crown materials, and if placed in a compromised location, or if the patient has a compromising habit like chewing ice, then it is more likely to break. One way the risk for breaking can be diminished is by bonding the crown to the tooth instead of just cementing it. There are many factors that go into the ability to have this be a great solution, so don't hesitate to ask me if this will work for your specific tooth.
This video explains a single-crown procedure: