Let’s face it: no one likes having a dental filling. Every time a filling, or “restoration”, is placed on a tooth, we commit the tooth to a restoration cycle. Unfortunately no material in dentistry lasts forever and so, in many cases, fillings need to be maintained and replaced over time.
The ideal material for a dental filling is long-lasting, strong and aesthetically pleasing. For a long time, no such material existed for placing in the dental chair. The procedure of placing a robust porcelain restoration on a tooth involved two appointments, temporary restorations and laboratory work beginning with messy physical impressions. With the advent of CAD CAM technology this changed: dentists were now able to place high-quality CEREC porcelain fillings in one quick and easy appointment.
What are CEREC fillings?
For sizeable cavities, there are two main material options available to place in the dental clinic. The first is the common composite (plastic) filling and the second is the specialised porcelain CEREC filling.
A plastic dental filling is a relatively cheap tooth-coloured filling that is placed while soft and activated to set hard with a specialised light. These fillings are less able to withstand heavy chewing pressure and may fracture easily. They also shrink as they are set – the bigger the filling, the more the shrinkage, meaning larger plastic fillings can become “leaky” and allow decay around their margins. They also tend to lose their colour and lustre over time and can look unattractive.
CEREC fillings, on the other hand, are made of porcelain. They are much stronger than their counterpart, and they keep their optimum shade and shine for the entirety of their life. CEREC fillings are made outside the mouth in a milling unit and are cemented, or glued, in to a prepared cavity, which means there is no shrinkage and hence no leakage.
Studies show the median survival time of composite plastic fillings is around 6 years, whereas CEREC CAD CAM fillings had success rates of over 95% after 10 years. It’s also interesting to note that plastic fillings tend to fail because of secondary decay, which is more destructive to tooth structure and nerve health in the long term; whereas the small amount of porcelain failures over 10 years were due to fractures within the porcelain, which doesn’t really affect the remaining tooth structure.
What can you expect at your CEREC appointment?
Luckily, CEREC filling appointments are easy, painless and fun! Many of my patients marvel at the state-of-the-art technology that allows us to give our patients ideal treatment. When you arrive, your tooth will be numbed up and prepared for the CEREC filling. I will then take a scan of the prepared surface and of your bite. After this, you can take a break and unwind while I design the filling on the CEREC software and it gets milled from a white porcelain block. This is then tried into the mouth and the fit and bite are checked. Once everyone is happy with the result, I cement it in with a strong chemical glue that powerfully bonds to both the tooth and the porcelain. This ensures the whole structure is one cohesive unit. After cementing, we give the filling a good polish and you are back to normal straight away!
Posselt A, Kerschbaum T, “Longevity of 2328 chairside CEREC inlays and onlays”, International Journal of Computerized Dentistry, 6: 231–248
Mjor I, “The reasons for replacement and the age of failed restorations in general dental practice”, Acta Odontologica Scandinavia, 1997; 55: 58-63