Advantages and Disadvantages of Zirconia Crowns

Advantages and disadvantages of Zirconia Crowns

The new era of dental materials is flourishing and much has to do with the advantages and disadvantages of Zirconia Crowns. Zirconia is an extremely strong and hard materiel, close to 1200 Mpa, compared to  a traditional full porcelain crown at 250mpa. We measure in MPA’s or mega pascals. It is white and relatively opaque. So it is a great replacement for the previous metal that was used as a base underneath PFM’s, or porcelain fused to metal crowns. PFMs, were the standard of esthetic dentistry for the last 60 years or so.

Advantages and disadvantages of Zirconia Crowns

We are all familiar with the white crowns, that were relatively opaque, sometimes you sawAdvantages and Disadvantages of Zirconia Crowns a little metal sticking out at the gum line, causing a dark area at the neck of the tooth. These teeth were also often opaque and not terribly natural. This was because the  metal had to be hidden by an opaque white color, so as not to see greyish in the crown.One problem was that the porcelain can chip off of the outside of the crown revealing an ugly grey color.

Zirconia crowns have overcome these problems. The zirconia comes either in small blocks that can be milled in a CEREC machine, or, as one of the few dentists in Israel with a Sirona Inlab system in my office, I can mill large restorations  out of a puck of zirconia. Zirconia in its raw form is chalky. We mill it dry, and it needs to be put into an oven for 12 hours to sinter, or become hard. But once hard it is strong, tough and very exact in terms of its fit. One of advantages and disadvantages of Zirconia Crowns is that they are brittle. So we must be careful when adjusting the so as not to cause microscopic Advantages and Disadvantages of Zirconia Crownscracks which can lead to failure. All in all it is an amazing material and the  advantages and disadvantages of Zirconia Crowns  are far outweighed by the advantages.

Porcelain Crowns

Porcelain Crowns

Porcelain has the unique ability to mimic natural teeth. They are a bunch of different types of Porcelain Crowns and each has its own advantages.

Traditional feldspathic Porcelain Crowns

These are a glass ceramic that achieves a high degree of aesthetic result, can work for decades. It is usually applied by hand using a porcelain powder. The technician builds up the crown using a paintbrush and is able to layer different subtle shades into the crown. It is used as a veneering structure on porcelain fused to metal crown (PFM).

Porcelain Crowns

different types of Porcelain Crowns

Glass ceramics with fillers

These different types of crowns are very ethic as well and much stronger and fracture resistant that a regular glass ceramic crown. They are also suitable for CAD-CAM systems allowing the dentist to scan the tooth in the mouth and create the crown digitally and then have the machine mill the crown out. One type of porcelain is E-max cad. It is Lithium dislocate materiel that comes in blocks. They are blue in color since they have yet to polymerize completely. Once Porcelain Crownsthe crown is prepared, the crown goes into a porcelain oven and we glaze it to make it shiny and we can give it some color to mimic natural tooth shades. It is really quite an amazing materiel. It then gets bonded onto the tooth with composite cement.

Glass-Free Ceramics, Polycrystalline

 These are materials with alumina and zirconia Porcelain Crownszirconia. Porcelain crowns made out of these materials are very hard and durable. They are almost impossible to break and might be a good choice for people that grind their teeth. The one problem with them is that they are not so aesthetic and ignored to use them a layer of porcelain needs to fused onto the outside of the zirconia.

 

Esthetic Crowns

Aesthetic crowns These aesthetic crowns crowns manufactured from materials that are integrated with the tooth color. If you made the best possible way these crowns can fit in so perfectly that will be visible that the crown and the natural tooth. This is especially important aesthetic dental Hkdmiot.ctrim When is capped aesthetic? There are several cases where required to put a crown on Shen This can be after a root canal, tooth cracked or decayed tooth removed much when it is not enough tooth left to hold regular blockage. In all these cases required a crown, but the problem starts when it comes to front teeth which is very high aesthetic importance. This is where the role of aesthetic crowns.

Crown differential is called PFM crown and contains a metal inner layer and above a layer of white ceramics and white coloring gives the crown. These crowns problem is often reflected through the metallic paint ceramic layer and gives a grayish tinge and a metal tooth. Crowns technology CAD / CAM Modern technology has given the opportunity to create a particularly aesthetic crowns with equipment connected to the computer. Required crown designed using computer commands later sends special equipment that generates the crown as planned. The materials used in this type of crowns materials are colorless and thus solved the problem of the metal reflection through ceramics. Both materials are used extensively oxidized aluminum and zirconia. For more on updates on Zirconia crowns see Advantages and disadvantages of zirconia crowns

Aesthetic crowns

Dealing with front teeth treatment is very important to choose the most suitable materials and the most aesthetic to create a perfect smile . These materials allow.

Emax cad porcelain now being used with Cerec

Emax cad porcelain

Emax cad porcelain is a new materiel being used to make dental crowns. It has numerous advantages over standard porcelain. The Cad in Emax cad porcelain stands for  computer aided design , being used by the CEREC SYSTEM that allows for the manufacture of a CEREC crown in the dental office in  an hour.

Emax cad porcelain is a material called  lithium disilicate. It is exceptionally natural in its appearance and is hard to differentiate from natural teeth. But the greatness of this porcelain material is not in its beautiful esthetics, but rather in its strength.Emax cad porcelain

Porcelain strength

In general, dental porcelain is a strong materiel. It has great strength under compression. Imagine putting a piece of glass on a perfectly flat surface with 1 drop of water under it. Drive a car over it and it won’t break but put one grain of sand under and it will. It has poor resistance to lateral forces or flexural strength. Porcelain strength is measured in  MPaS or megapascals. Regular porcelain has something like 150 MPa’s but Emax cad porcelain is in the order of 400MPA’s. More than 2 times as strong as a regular porcelain crown with esthetic advantages.

When we make a CEREC  Emax cad porcelain crown, it comes in a block that is not fully formed and once the crown is manufactured, it needs to be fired in a porcelain oven to be completed and brought to strength. It is quite fascinating as the materiel has a blue colorEmax cad porcelain until it is removed from the oven when it takes it’s final beautiful shape and hue.

Depending on the situation, we use this material for many of our crown solutions.The  translucency,opalescence, and light diffusion properties of IPS e.max lithium disilicate were all designed to copy natural tooth for beauty and quality restorations.

computerized dentistry in Israel

Computerized Dentistry

Israel has long been at the forefront of computerized dentistry. The use of digital x-rays , CT’s and CAD-CAM  dental restorations has been around for  20 years or so. We were the first office in the country to adopt the CEREC porcelain dental crown system.

Having just upgraded to the new Cerec Bluecam, I wanted to share some thoughts on what this means for my patients. CEREC blue cam is a state of the art dental 3d capture device. It allows us to avoid taking messy goopy impressions of your teeth, and allows a simple digital image to do the job.CEREC blockcomputerized dentistry

Then, on the screen we design your restoration together and we see magic as the computer itself makes the crown fit between your teeth. Some adjustment is usually necessary by the dentist but we quickly reach the point where with the press of the button the milling unit literally create the crown out of a block of porcelain. It is computerized dentistry at it’s finest.

Here is one of the advantages of the new CEREC 4.2 software. It allows computerized dentistry to actually fit the models of the upper and lower jaws together digitally. It shows me exactly where the teeth all touch allowing our final restoration to have a perfect fit and bite.Cerec occlusion computerized dentistry

Computerized dentistry has come into it’s own in the last decade or so. We can now restore dental implants using this system, as well as doing porcelain veneers. The fit is unparalleled and the esthetics and time savings are tremendous. There are a host of new materials  that have been developed for this system and I have no doubt that we will see even greater advances in the future.

For now we can say without a doubt that CEREC is at the forefront of computerized dentistry and that it offers an unparalleled  service to our patients.

CEREC Before And After  Smile Design

CEREC before treatment CEREC AFTER

Cracked Tooth Syndrome

Cracked Tooth Syndrome

Cracked Tooth Syndrome is something we see dailing in the dental office. The teeth in our mouth are brittle and have a tendancy with age to break. Another factor in the

cracked tooth syndrome Jerusalem dentistbreaking of teeth is if they have big old fillings. The minute a tooth has a filling it has lost some integrity and begins to loose strength. Cracked Tooth Syndrome happens when we have such a fracture. Often times that crack is not visible. The crack can either be microscopic in nature or in an area that is not visible to the eye. Cracked Tooth Syndrome is usually diagnosed more by symptoms and less by actual visual inspection of the tooth.

Click Here for a video on cracked tooth syndrome

Cracked Tooth Syndrome And Root Canal

Patients often come in  needing a filling. When we remove an old filling, and look at the floor of the preparation, we can sometimes literally see a crack or craze line run-

cracked tooth syndrome jerusalem dentisting along the floor of the tooth, like in the picture . Should that crack propagate further down the tooth, it will reach the actual nerve and blood vessels in the tooth and Cracked Tooth Syndrome will end up causing the tooth to need a root canal. There are times that the tooth actually breaks along the line and sometimes that fracture is so deep under the gum line that there is no way to save the tooth.

 

When Is A Tooth With Cracked Tooth Syndrome Salvageable ?

The minute you begin to feel these symptoms Cracked Tooth Syndrome israel dentist of pain on biting or pain on releasing, you should see your dentist. Often times, If we can diagnose the tooth requiring treatment, a crown can solve the issue. A crown acts like a band that holds that tooth together and prevents the crack from getting worse. A treatment like this can actually save the tooth and prevent Cracked Tooth Syndrome from requiring you to have your tooth extracted.

NY Times on CEREC

NY times on CEREC

OCTOBER 8, 2012, 3:00 PM

high tech dentistry

 

I was chewing a piece of steak on a Saturday night last month when an old filling shattered. Suddenly, along with steak I had chunks of gray amalgam and shards of tooth in my mouth. I felt the hole with my tongue — it seemed as large as a crater.

 

The Digital Doctor

 

In this special issue of Science Times, we look at some of the many ways that technology is changing the world of medicine.

Go to Special Section »

My dentist later confirmed that I now had a big hole in a molar, too big for a filling. But, the dentist said, if I could spare an hour he could make a crown and put it in, right then and there.

 

An hour? Aren’t crowns — those tooth-shaped caps that fit over teeth — supposed to require at least two visits? First, the dentist numbs the area and drills the tooth, filing it down to make room for the crown. Then, he or she makes an impression of the tooth to send to a lab. The hole in the tooth is covered with a temporary filling while you wait for your crown.

 

It arrives at the dentist’s office two or three weeks later. You return for another appointment. The dentist numbs the area, removes the temporary filling and glues the crown in place.

 

Now, new technology has produced a better way. My dentist happened to be one of the approximately 10 percent who use CAD/CAM — computer-aided design and computer-aided manufacturing — to create a crown while a patient waits. The result is a ceramic crown that can be glued in place. You are done less than an hour after you first sit down in the dentist’s chair.

 

Maybe you think that dentists are stuck in the technological dark ages, waving pliers and babbling about fluoride. In truth, the profession has quietly embraced sophisticated technology, and I was lucky enough to stumble upon a prime example.

 

The process starts the same way it used to: The area is numbed, and the dentist drills the tooth to shape it for the crown. But instead of making an impression of the tooth, the dentist uses a tiny camera to create a three-dimensional image of the drilled tooth. A computer program uses that to construct an image of what the tooth will look like with the crown in place. I could see it on the computer screen — a tooth that looked just like mine would when I left the dentist’s office.

 

 

 

Then all the details — the size and shape, the little ridges and indentations — are transmitted to a machine in an adjacent room that mills the crown from a chunk of porcelain. The result is an exact replica of what I saw on the computer screen. When the crown is ready, about 15 minutes later, the dentist glues it in.