Choosing the Perfect Type of Dental Crown
A dental crown (often referred to as a crown – or a cap) is a tooth-restoring apparatus. Its applications are many. Primarily, a crown is used when a tooth is accidentally cracked, severely decayed to the point where fillings won’t suffice or when its cavities are so extensive that a large amount of it gets drilled away. Crowns are also employed to strengthen anchor teeth to support a bridge or to create a tooth on a dental implant.
A dental crown’s shape is usually determined by an impression (or indentation) that a dentist takes of a patient’s teeth after filing the damaged tooth down. A crown can fill out a tooth’s shape or it can completely encase a tooth. Either way, it should fit snugly and be shaped naturally into the mould.
A crown provides both aesthetic and therapeutic solutions. It often fills an unsightly and unhealthy gap in a set of teeth. It can help to preserve the shape of a patient’s jawline, prevent surrounding teeth from shifting and protect further damage to the tooth and bone beneath it. A crown is generally affixed with cement.
Interestingly, the first known use of dental crowns was by the Etruscans, a civilisation that existed in the region that is now central Italy – around 160 A.D. Dental crowns are nothing new, but new technologies (including computer aided design and 3D printability), as well as better materials, constantly improve the appearance, comfort and strength of dental crowns.
You may select your crown material based on one or more of these variables: a patient’s budget, the location of the tooth to be repaired, the strength or length of repair that’s required, or the thickness of a crown’s material in relation to how much of an original tooth can be preserved. In some cases, you may also select a material that is better recommended for patients with allergies or auto-immune conditions. Below are some of today’s most commonly used dental crown materials and the fundamental features of each. For more in-depth information, please follow the individual links.
IPS (Ivoclar Porcelain System) Emax Crowns
- Free of metal.
- IPS crowns are made of a ceramic material called lithium disilicate ceramic and are less prone to causing sensitivity issues than metal.
- An ideal choice for visible teeth. Their natural appearance, texture, translucency and colour blend beautifully with original teeth.
- Strength and thickness are both moderate.
- Free of metal.
- Zirconia is a type of crystal and is less prone to causing sensitivity issues than metal.
- Zirconias are not as natural looking as IPS Emax Crowns. They’re more opaque and not as ideally colour-matched (though improvements to this are already in the works).
- Their strength is higher than that of IPS Emax; they are also thinner and allow for more tooth preservation.
Porcelain Fused to Metal (PFM) Crowns
- An outer layer of porcelain is heat fused to an inner foundation of metal. Various metals can be used, from semi-precious to highly precious; cost is usually the determining factor.
- PFMs are opaque due to their metal core. In the case of gum recession, the inner metal can also be exposed by the gum line. Chips in the porcelain will additionally expose metal, so they are less aesthetically pleasing than IPS or Zirconia.
- PFMs are of moderate thickness (similar to IPS) and of great strength and durability. They have toothlike chewing power.
- PFMs are often preferred for use on back teeth and for anchoring major bridge work.
If we can answer any questions for you about dental prosthetics or for more information about our Australian dental lab services, please contact us. We look forward to assisting you.