Dental crowns are one of the best ways to protect badly damaged teeth. In most cases, crowns are needed on back teeth that may have needed a root canal treatment. For front teeth, the most common reason for the need of a crown is due to trauma . This could be from a childhood playground accident or a sports injury for example. Ouch!

If a front tooth crown was placed many years ago, over time there will have been changes in the mouth including the level of the gums and the shape and colour of the teeth. This often why there is a 'black' line around old crowns where the gum has receded and the underlying root becomes visible. Older crowns will have been made with a metal base, called a metal ceramic crown and the metal can also show as the tissues change.
 

Our case of the month for September 2022 is a lovely smile transformation done the Progressive Dentistry way with invisalign full, teeth whitening & a new front dental crown. When we plan these types of treatments, we often will look at whether the teeth are in the right place first. Why is this so important? Well the reason is simple. If the teeth are not in the right place or well aligned, any cosmetic treatment will be a big compromise. For instance, in the days gone by, there was a fad for porcelain veneers and crowns. If the teeth were wonky to start with, this would mean having to cut a lot of healthy tooth to make the ceramic veneers or crowns. This is not a good idea! For every heavily prepared tooth, around 17-20% of the nerves die. This means root canal treatment and a risk the tooth will not last a life time.
 

Our case of the month for April was one involving E Max crowns by Ivoclar, which is our opinion, give the best aesthetic results. In the past, tooth coloured dental crowns had a layer of metal underneath for strength with the ceramic bonded on the outside. Now these could look perfectly acceptable but there were issues. Having two layers means that more of the underlying tooth has to be cut down to accommodate the material. For any of you that has read any of our posts knows that we believe in minimally invasive dentistry, cutting away more tooth than necessary just does not sit right with us. Another issue with metal ceramic crowns is that the metal layer may become visible over time as the gums recede which gives that classic grey line around the tooth. Not very desirable. One of the main advantages of ceramic crowns is that there is no metal underneath and this grey line will never be an issue. 

The aesthetic qualities of E max crowns are second to none. Our case shows that the crowns can be fully customised with translucency at the edges, varying shades, light reflection and opaque areas to name a few. The skill of the dental technician plays a huge role here and we work with some excellent laboratories know for excellence. 

For our case, Ceramic Studios in Kensington made the wonderful E max crowns fully which were fully customised.
 

Our case of the month for February involves the replacement of a single front tooth crown. Although this may seem a simple process, the technical skill involved in achieving a great match to the adjacent teeth is incredibly high. 

A dental crown is often needed if a tooth is badly broken, decayed or has had root canal treatment. Heavily damaged teeth will not be able to withstand the everyday forces of eating, chewing or grinding and may split or fracture. If the fracture is below the gum level or between the roots, the only option will then be removal of the tooth. 

The process involved with a crown has changed now that we use a fully digital approach. The only physical impression we need is a small one of the tooth to be able to make a temporary crown. The tooth in question will be prepared to approximately 0.8mm-1.2mm all around with a taper of 6-12 degrees. A vital aspect is something called a 'ferule'. This is where the preparation ends on tooth surface rather than a filling material. If a ferule of 1-3mm can be achieved, the retention and resistance form is very high leading to a long lasting treatment. Your dentist will be able to tell you if this has been achieved. 

Once the tooth has been prepared, it is usual for some level of gum 'retraction' using either pastes, cord or a combination of both. This is important so that the margin of the preparation is clear. This is where the crown will sit and hence if the margin is clear, a good fit will be the end result. We will then take a digital scan of the tooth and surrounding areas including how you bite. There is no need for messy, sticky impressions! On the software we can check that there is enough space, check the margin, shade test the adjacent teeth and check the angulation/ taper. 

Then it is time to make the temporary crown. This is usually from a bis acryl composite material and seated with a soft cement. Our labs will ask for 10 working days in most cases where the scans will be printed and the new crown designed, milled, characterised and glazed ready for fitting. The fitting appointment is usually straight forward with perhaps a slight adjustment. Once fitted, the crown will take a few days to get used to. After that, it will feel part of your mouth. Here are the photos of our case: