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:
 

Our case of the month for October 2018 is one which involves a fully customised crown. What is this, you may ask. Well, we mainly advise a fully customised crown for single front teeth where the aesthetics are incredibly important. Essentially, this technique is the very best we can offer in terms of aesthetic dentistry. The process involves:


1. Full planning and diagnostic wax up if required.

2. Initial shade testing at the laboratory to ensure the base shades are all correct

3. Preparation of the front tooth and records. We now use intra oral scanning which eliminates the need for messy dental impressions.

4. Placing a temporary crown made from a mixture of acrylic and a resin.

5. Trying in the crown prior to any final customisation to ensure that the fit, margins, emergence profile, embrasure spaces, contact points and bite is all fine.

6. Placing the temporary with a soft cement and then a journey to the laboratory straight after the try in.

7. Full customisation of the crown until you are 100% happy with the overall aesthetics.

8. Straight back to the practice for fitting.


Although this may seem a long winded approach for one single tooth, we can assure you it well worth the effort. After all, it is your front tooth! Here are some photos of a recent case: