An alloy is basically a blend of materials. Alloys are useful because they combine the best characteristics of the elements used to make them, which creates a resulting metal that is more chemically stable and with superior properties than the pure elements could have alone. This means alloys can be specially engineered to possess the ideal physical qualities for specific purposes, such as in dentistry: greater strength, resistance to corrosion and wear, and the structure to be easily fabricated and adjusted by the lab technician and dentist.
In general, there are three basic categories of dental alloys that can be used to make crowns. They are: high noble alloys precious metal , noble alloys semiprecious metal and non-noble or base alloys nonprecious metal. Noble metals are resistant to corrosion and oxidation in moisture or air, are not easily attacked by acids, have high biocompatibility, and retain a shiny metallic surface when under heat treatment.
The noble metals used in dentistry are gold and those from the platinum group, most commonly platinum heavy category and palladium light category. Precious metals are defined as rare, naturally occurring and of high economic value. They are also extremely malleable able to be bent without breaking and ductile able to be stretched.
Noble metals have the advantage that they are the easiest and most predictable to work with, ensuring the most accurate fit and bond. The rest of the alloy is made up of base metals such as tin, copper and iron which help form an oxide layer to provide a chemical bond to the tooth. These are also referred to as base metal alloys.
They are more reactive to atmosphere than noble metals and will oxidise, tarnish and corrode relatively easily when exposed to moisture, air or acidity. Examples of base metals include aluminium, copper, nickel and tin. Base metals are more challenging for lab technicians and dentists to work with as they have a very high melting temperature, making soldering and casting difficult.
They also exhibit shrinkage during casting which must be compensated for. An advantage of base metals is that they are much harder and stronger than noble metals, and exhibit twice the elasticity. Therefore alloys can be made into thinner crowns whilst still retaining the rigidity required for dental applications.
However their hardness also makes them difficult to burnish and polish. Two common types are titanium alloys and alloys made from a mix of cobalt, nickel and chromium which increases corrosion and tarnish resistance. Nickel free can be used if a patient has allergies. An all ceramic crown is referred to as an ITEM you will see this on treatment plans and invoicing from your dentist. All ceramic dental crowns provide a natural appearance and colour match that is amazingly lifelike and unsurpassed by any other type of crown.
The lustrous, glistening optical quality of a natural tooth is generated by the way light passes through the tooth and is then reflected out. The goal in the creation of a ceramic crown is to mimic the light handling characteristics, and therefore appearance, of a natural tooth. Generally speaking, the best way to achieve this effect is to use very translucent porcelain in a thick layer.
All ceramic crowns are the most natural looking option for front teeth. They are also a good choice for patients who have allergies to particular metals used in other types of crowns.
Some disadvantages of ceramic crowns are that they wear down opposing teeth more than metal and resin crowns do, but they are still less abrasive than porcelain-fused-to-metal crowns which we will discuss later. They also require more tooth structure to be removed than for example metal crowns because of the thickness of porcelain required for sufficient crown strength with the exception of Zirconia crowns which are explained below.
The major risk with ceramic crowns is that they can fracture, which can lead to infection and failure if not treated appropriately by a dental surgeon. There are many different types of ceramic crowns and brands of materials available. Some of the main kinds are:. Feldspathic porcelain is the traditional, standard porcelain material that has been used to create crowns for many years.
It is a luminous material that offers a very natural and translucent appearance. These crowns are created by custom layering the porcelain and can either be bonded directly to the natural tooth surface which transmits the underlying tooth colour through the porcelain , or layered over a pre-built core for example from Zirconia — see point 2 below.
Zirconia crowns are the hardest and strongest type of ceramic crown available. Zirconia is a type of crystal that is extremely durable and virtually indestructible, which is why these crowns are so long wearing and withstand biting and chewing forces exceptionally well. They are colour matched to the natural teeth, however are not as translucent and light-reflecting as other porcelain crowns due to the very opaque colour of the ceramic. They can also be abrasive and there is greater risk of them wearing down the opposing teeth.
Unlike Zirconia, this material is more porous and can therefore be acid etched before cementation, which creates a chemical bond between the crown and tooth making the adhesion very strong. They are also the most aesthetic type of porcelain crowns available as they have excellent translucent light-reflective properties, which results in the closest match to natural teeth. Procera, Empress and Emax are three different kinds of aluminous crowns and we will discuss them each below:.
Procera crowns are made through a two-layer system. Then feldspathic porcelain is stacked in a superficial outer later to give the crown more translucent, lifelike aesthetic properties. Procera crowns are exceptionally strong. Empress is more like glass than porcelain. Unlike normal feldspathic porcelain which is baked, Empress crowns are cast and give a more precise fit.
The inner core is made out of medium-strength pressed ceramic, and then a highly customisable, superficial glass is layered over the top. Emax crowns are made out of a lithium discilicate glass ceramic that has exceptional strength, translucency and durability properties. They are very biocompatible in the mouth and have excellent long term wear characteristics similar to that of natural enamel the outer layer of your teeth.
They are strong enough to be made into very thin layers and still easily withstand biting and chewing forces. A porcelain-fused-to-metal crown is referred to as an ITEM you will see this on treatment plans and invoicing from your dentist. PFM crowns are made up of two components. Porcelain which is a type of ceramic is then layered over and bonded to the metal base to give the crown its tooth-like shape and colour.
In a way a PFM crown gives the best of both worlds for strength and aesthetics, which means they are a suitable choice for either front or back teeth. Next to all-metal crowns, they are the second most long-wearing choice. The metal core is very hard and durable, and is able to be acid etched unlike Zirconia cores, which you can read about above for strong adhesion to the natural tooth. The porcelain that is layered on top to make up the visible portion of the crown creates a very attractive, lifelike result that is matched to the natural teeth colour.
PFM crowns also have excellent biocompatibility properties. Next to all-ceramic crowns, PFM crowns most closely resemble natural teeth. However there is still quite a difference in similarity, because in comparison to a full-ceramic crown, PFM crowns are almost non-transparent. The way all-ceramic crowns look so lifelike is by imitating the way light passes through and is reflected off a natural tooth, through the use of very translucent porcelain. Because the metal core of a PFM crown is so dark, it needs to be covered in very opaque porcelain as a mask so that none of the metal colour shows through.
As a result, only a comparatively thin layer of translucent porcelain can be fit on the top, which reduces the ability to truly mimic the lustrous look of a natural tooth. Some other disadvantages of PFM crowns are that over time, especially as the gums recede, the underlying metal can show through as a dark line. The type of porcelain used is also quite abrasive and can wear down opposing teeth.
The major risk with PFM crowns is that the porcelain layer can fracture, which can lead to infection and failure if not treated appropriately by a dental surgeon.
This patient has bonding done on her left front tooth years ago. Over time it discolored and chipped slightly. Our goal is always the same, to create well functioning, natural looking restorations.
We accomplished our mission! This was interesting. This woman lives in Europe and is a sister of one of our patients. I removed what had been placed on her teeth and used 4 different shades of bonding material to obtain this outcome. She was happy and so were we! Here are close up views of this bonding replacement. Another satisfied patient! We placed porcelain veneers on his top teeth to give the appearance of straight teeth. He was happy and so were we! Even teeth with cavities should be restored to their original shape.
Here is an example of what a cavity looks like initially, after the decay is removed, and after the tooth colored filling is placed. Both form and function are addressed. This is another tooth with a cavity that is restored with a tooth colored filling to its natural shape and appearance. This is a common tooth issue, called a peg lateral for obvious reasons. In one appointment we used bonding material to create the tooth appearance that was meant to be. She now smiles with confidence!
This patient wanted his 2 front teeth to match. He had old bonding on 1 tooth and a cap on the other. In 2 appointments we made him 2 new crowns caps that are natural looking and feeling.
We removed all of the bonding material that was on the teeth and gave her what she wanted. This woman in her 70s never liked the fact that her sister had nicer teeth than she did. I think we solved that problem by placing crowns on her upper teeth. The range depends on whether or not you have insurance, what your insurance policy actually covers, the dental fees charged by your dentist and how many added procedures are needed to complete treatment.
The pros of this procedure are lower cost and less time in the chair usually one visit. The cons are durability. Indirect resin crowns are recommended as a budget-friendly low term solution. But it is not meant to last years and years like crowns do. According to an estimate made by Costhelper , the price range of dental crowns per tooth today can be as follows:. But everything will depend on the type of insurance you have, and your particular case.
If the crown is part of a cosmetic treatment, your insurance plan will most likely not cover the cost of it. But if the treatment is preventative to cover a root canal or repair a broken tooth the cost can be covered by your insurance or at least a percentage of it.
Cost will also vary depending on whether you go to a in-network vs an out-of-network dentist. If you like your dentist, has good reviews or comes highly recommended, it might be worth paying for that added peace of mind.
Your best bet is to set up an appointment with your preferred dentist first. Have their staff do a complimentary insurance check to see what your dental insurance will cover and what your portion will be. A dental crown is a long-lasting restorative treatment. That means you will have a crown for many years in your mouth.
Certainly, you want to have it done in the most professional and skillful way. So, if possible, when considering types of dental crowns and cost, try not to go directly to the least expensive dentist without analyzing your options. Weigh in all factors before deciding. Choosing only cheap options may lead to poor quality treatments which, in turn, will mean more money, more time and more discomfort in the future.
You should also check if your dentist works in-network or out-of-network. Even dental offices work out-of-network will do their best to file all the claims for you so that you can get directly reimbursed to your home once the treatment is over.
Sometimes going out-of-network of assigned providers can ensure better quality care and overall improved experience. There are different types of dental crowns. Gold crowns are very durable and strong, which is why they are used in back teeth restorations. All-porcelain crowns are the most widely used type of crowns for their natural look and metal-free composition.
Porcelain-fused-to-metal are less costly. They look like natural teeth, although the metal composition may cause a grey colored gum line over the crown. Zirconia Crown are made of a new type of material that provide both excellent aesthetics and strength. Emax crowns are similar to zirconia crowns in strength, look and price. However, prices will vary depending on the type of crown chosen. Fees will vary according to the treatment you need before the final crown is cemented, so if you need bone grafting, a root canal or gum surgery, the price of a crown will go up.
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