Root Canals Explained

What is a root filling, why are they so expensive and why do they fail?

Dentistry, as with all forms of medicine, continues to evolve with the ever-increasing knowledge we gain as the years go by. This applies to the procedures known as root canal treatment and dental implant therapy. To explain what root canal treatment is, I will need to describe the structure of a tooth. The outer layer you can see in your mouth is made of enamel. Underneath this is a slightly softer layer called dentine. Then further down, you find the part of the tooth that anchors the tooth into your jaw bone. These are the roots and can number one ( usually for the teeth at the front of the mouth) to four, five or even more for the teeth at the back (the molars). These roots are hollow and have canals that run inside them; these are the root canals. 

Then, in the centre of the tooth, there is a space filled with nerves and blood vessels. This is called the pulp chamber. Finally, hanging down from the base of this pulp chamber are branches of these nerves and blood vessels. Each unit runs down the inside of the root canals. We used to think there was a single canal inside each root, but now we know it is quite a complex structure with a whole network of offshoots. 

Root canal treatment is required when the nerves and blood vessels inside the tooth have become so irritated that they die off. This can be due to many reasons, including bacteria causing decay deep inside a tooth, a large filling, a hard knock to the tooth, or even grinding your teeth! The symptoms when the tooth is dying off can range from severe pain to no feeling, but a dental abscess can ensue if left. The tooth then requires these dead nerves and blood vessels to be removed, and the canals inside the roots need to be cleaned and widened to remove infection and sealing.

At best, the success rates are around 85%. They can fail due to no fault of the dentist because, as I mentioned, the canals are a complex network, and it is impossible to ensure that every part is sterilised. Another cause is that there may be a hairline fracture of the root of a tooth. These do not show up on X-rays and are not visible.

I would recommend that dentists who specialise or have a particular interest in this procedure perform root canal treatments. For the best chance of success, these procedures can take up to 2 or 3 hours, and if not done to the highest standards the first time, the chances of success, if they need to be redone, comes down to around 60%.

After root canal treatment, it is recommended that the tooth is strengthened by placing a crown or onlay over the tooth, as root-filled teeth are more prone to breaking. These are metal fused to porcelain or ceramic ‘caps’  placed over a trimmed down tooth.

Generally, to be done to the highest standards, only private care is available in general practices. The costs can be increased, around £1500 to £1800 per tooth for the root filling and crown. Then if the root filling fails and the tooth needs to be removed, all that work and money is wasted, but there is no way of knowing if your tooth is one of the approximately 15% that ends up in this way.

The other option is to remove the tooth and fill the resulting space. The space can be left but is generally not recommended. Ways to fill the space include a denture, bridgework or a dental implant. Your dentist will explain all the pros and cons, but I will concentrate on dental implants. These are now the recommended treatment in most situations. Ideally, they be made from titanium and placed in the jaw bone where the tooth used to be. They are left for six weeks to 5 months to fuse to the bone. After that a tooth in the form of a crown, made of metal and porcelain or metal free products can be fixed to it. The advantages of dental implants are that they usually last longer than the alternatives, they help strengthen the bone, and they don’t require any trimming of the teeth next to the gap. The disadvantages include the initial costs and that surgery is required (although this is normally relatively minor). 

So which is better a root filling or dental implant? The general consensus in the dental profession is that it’s better to try to save a tooth first and do a root filling. But given that the success rates are roughly 85% and they are approximately 90 to 98% for dental implants there is an argument for removing the tooth and placing an implant. As if the root filling should fail, you may have paid around £1500 for it and a crown, then the tooth needs to be taken out and an implant placed. This may cost an additional £1700 to £3500.

 These are large sums of money, and in other parts of the world where private dentistry is the only option, people tend to be used to the costs. However, if you’re used to the NHS system it seems unthinkable to spend this on a tooth. So why is it so expensive? These procedures do involve complex surgical procedures carried out by usually highly experienced and qualified professionals. The materials used are expensive and if laboratories are used for crowns etc, then you have another highly trained technician spending hours creating a replica tooth that will look and function perfectly in your mouth.

In the end it’s an individual choice once given all the facts, risks and costs. I hope I have provided some of the background information needed to make an informed decision if you ever need this form of treatment. For any further information, please contact us at Bridgedental on 02074072174 or email