Fillings are hard substances that are put directly into/ onto teeth to restore either function or aesthetics, or both. A filling may be needed to treat tooth decay (cavities), a broken or worn down tooth or to replace an existing filling that has deteriorated. 

If the dentist has identified a cavity and advised you require a filling then they will discuss your options with you. The sooner you have the cavity treated then the better chance of success and the lower the chance of sensitivity afterwards. 

Sometimes you will be aware that a filling is needed as you will be able to feel a hole with your tongue, food may be getting stuck somewhere or you may be having discomfort. Sometimes you may have a cavity that is small and be completely unaware of it because there hasn't been any pain and the tooth is still intact. Sometimes cavities may not be detected when looking at the teeth but will show up when x rays are taken. It is best to have fillings done when the cavity is as small as possible as it is likely to be more successful. If the tooth has started to give pain already or broken down due to decay then more complicated treatment such as root canal and crown or extraction may be the only options left.  

The materials used for a filling are usually either amalgam (silver coloured) composite (tooth coloured) or GIC (white). The site and size  of the cavity will dictate which material is most suitable. 

NHS fillings in posterior teeth are usually silver as they are  durable and easier to place. If you would prefer a more aesthetic option you can discuss your options with your dentist. More cosmetic options such as composite are available privately. Composite restorations tend to take much longer to place which is why they are usually available as private treatment only for back teeth. 

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How is a filling done 
 

Fillings are usually placed under local anesthetic which involves a small injection to numb the area. The procedure usually takes between 20 minutes to an hour ( sometimes longer for difficult cases). Once the local anaesthetic has worked the procedure itself should be comfortable however there may be some noises and vibrations.  there may also be some jaw discomfort for longer procedures. 

Will it be painful afterwards

There is often increased sensitivity afterwards. The larger the filling the higher chance that it will be sensitive.  The dentist will try to warn you if this is the case however sometimes even small fillings can be sensitive afterwards. 

The sensitivity can last for up to eight weeks as the nerve in the tooth tries to repair itself. Use sensitive toothpaste and try to avoid very hot or very cold foods and drinks on that side. If the sensitivity is waking you up at night that's a sign that the nerve in the tooth won't be able to repair itself and root canal or extraction may be needed. 

After the procedure

If you had a silver filling it will need 2 hours to set enough to eat soft foods  on and 24 hours to set fully. White fillings will be set immediately. You should however always wait until the effects of the anaesthetic have worn off before eating or having hot drinks.