Dr. Amy Guthrie, Cerec Dentist Los Altos

One Visit Crowns with CEREC

There's something about the nature of dentists that draws them to new technology. But while many hi-tech tools look and sound amazing at first when you get right down to it, they don't have a lot to offer where it counts--helping patients. So our approach at Amy Guthrie, DDS. has been to wait for the technologies to mature and prove themselves before jumping onto the bandwagon.

Since 2002, we have been using amazing technology that provides incredible benefit to our clients. It's called CEREC (for CEramic REConstruction). It works by using a 3-D camera, computer software, and a small but sophisticated milling machine in the office to make a new “part” for your tooth.

​​​​​​​CEREC often works better in your mouth than traditional restorations while being far more convenient for you to have done!

Here's more information, organized as an FAQ (frequently asked questions). Click on your question to see the answer.

How is CEREC better for my mouth?

CEREC has lots of nice properties we've been looking for since before Paul Revere used walrus teeth on George Washington:

Tooth Compatible
The ceramic material used in CEREC is as similar to the natural tooth (enamel) as anything yet devised. The hardness and abrasiveness are very similar to the natural tooth, so we don't have to worry about the CEREC beating up on the opposing tooth, or being worn away by it.

CEREC material also expands and contracts with heat and cold much like the natural tooth, allowing less stress to your teeth when you eat and drink hot or cold things.

Lets you keep more natural tooth
CEREC restorations are bonded (glued) into place, effectively replacing the missing part of your tooth to form a continuous structure. To make sure Traditional restorations stay in place, otherwise healthy tooth structure must be cut away to provide the shape needed to lock in the restoration (mechanical retention). Often, CEREC allows the dentist to limit cutting to only the damaged part of the tooth.

For traditional restorations, you'll typically need to wear a soft "temporary tooth" for two weeks or more while the lab makes your final restoration. The problem is that thinner, weaker areas of a tooth are not well supported by a temporary, and could easily break during that time. So the dentist has to cut down those parts to make sure the tooth is strong enough to last with a temporary. Since no temporary is needed with CEREC, the dentist is free to keep every bit of tooth possible.

Here at Amy Guthrie, DDS we think to keep your natural tooth intact a very good thing.

Looks like a tooth!
The CEREC material comes in various colors that closely match most natural tooth shades. In fact, it's often difficult to spot the restoration after it's bonded into the tooth.

If you've had an inlay, onlay, or crown done, you know it's a bit of a hassle. You have to make two trips to the dental office two weeks apart, and in between you have to wear that temporary that, no matter how hard we try to make it right, is always a little bit uncomfortable, ugly, and weak, and then it sometimes falls out, so you have to make yet another trip to the office.
Well, CERECs are usually done in just one visit! That means:

  • Only one trip to the office

  • No yucky goo in your mouth to make a mold of your tooth (it's done with a 3-d camera)

  • No temporary to mess with (including saving the 1/2 hour it typically takes to make it)

  • If you need to be numb, it is only one time, not twice.

Thanks to the translucent, tooth colored ceramic and the blending nature of the bonding agents, a tooth restored with CEREC looks like a tooth. Some people have teeth with different colors in the same tooth, and CEREC may not be the best way to restore a front tooth in a case like that, but much of the time you can't even see the CEREC after it's installed and polished.

It usually takes Dr. Amy about 2 hours to complete a CEREC restoration. There is a 20 minute break in the middle of that where you don't have anyone's fingers in your mouth. This compares to 2 1/2 or 3 hours over 2 separate visits for a traditional crown.

CEREC is a form of indirect restoration. For indirect restorations, the tooth is prepared, then a new piece is manufactured outside of the mouth. With CEREC that happens in about 20 minutes while you relax. With these others, it takes about 2 weeks while you live with a temporary. All the indirect restorations are close to the same price. Here's the rundown:

Skilled technician can do good "art" to produce very natural looking result
  • Glazed and fired so harder and more abrasive; can wear and stress the opposing tooth
  • Difficult to fine-tune the fit without damaging the look and feel of the material
GoldStrongest and toughest material available; good for back teeth of heavy chewers
  • A lot more tooth must be removed to provide the thickness and mechanical retention needed
  • Gold color stands out
on Gold
Compromise between pure porcelain and pure gold; still fairly strong but also natural looking
  • Requires removing the most tooth structure to fit the gold and make room for the porcelain
  • Fired porcelain can wear on other teeth
  • The porcelain can chip off of the gold over time

Indirect restorations add a lot of strength to the tooth. They are needed when there is a crack in the tooth, or a hole that is so big that a regular filling would cause the tooth to split apart under the stress of biting.

The materials used in CEREC are the same as those that have been used safely for a great many years. The difference with CEREC is how the restoration is made, not what it is made of, so while it's impossible to be 100% certain that no person out there can have a bad response to the materials, they have a long track record of being safe and reliable, and are widely accepted as the standard of care by dental authorities.

The joy of technology that actually works: we're able to offer the many advantages of CEREC at the same price level as the other indirect restorations. Most dental plans provide the same coverage for a CEREC as they do for a full-coverage porcelain-on-gold crown.

CEREC is only one of many tools we can use to keep your smile healthy and your chompers chomping. We're happy to talk with you about your individual needs and priorities. CEREC may be right for you if:

  • You want to keep as much of your own natural tooth as possible

  • You want to minimize the number of trips to the office

  • You want your teeth to look as natural as possible

CEREC may not be the right thing for restoring a badly damaged tooth in an area where you chew very hard, or for restoring very small cavities.

This part is for the techies, so don't say you weren't warned!

The initial preparation of a tooth is mostly similar to traditional methods. The area is numbed if required and the surgical field is prepared, typically with either a rubber dam or an Isolite. Then a handpiece is used to removed the damaged tooth structure and prepare the proper shape to receive the restoration. The dentist removes the damaged area of the tooth, and ensures the tooth is shaped so that the camera will be able to "see" all of it (no part is hidden behind another part).

After the preparation is complete, an inert, uniformly reflective powder is spread over the tooth. This compensates for varying optical properties of the tissues in the mouth. Then the wand-like camera is placed just above the tooth and several images of it and its neighbors are recorded. The camera uses its own built-in infrared light source and special sensors to capture a very accurate three-dimensional model of the tooth surface. For each position (pixel) in the image, CEREC captures position (X, Y, and Z) data instead of the color data that would make up a normal digital picture. Strictly speaking, it is doing surface mapping rather than image capture.

Now the patient gets to relax and the real fun begins. This is where the dentist's skill shines, customizing the look and fit your specific needs with the design softhware. This is the part that requires extensive training and experience, and with well over a thousand resotrations with CEREC, Dr. Amy has that experience. (Let's put it this way, in 2014 the technician who covers all of the northern California told us he had never seen another milling maching with anythere near the runtime for Dr. Amy's.)

After the design is complete, an ingot of ceramic is loaded into the milling chamber, and the computer controls the special diamond-tipped cutters as they mill the desired shape to within 20 microns in abotu 10 minutes.

After milling is complete, Dr. Amy touches up the fit of the custom-made restorations and bonds it into you mouth. The final touch is to polish it smooth, and then see if you can find it in your mouth!

You can ask us, or you can check out CEREC Online for many details.