Fillings are required when a tooth is in the early stages of decay. Left untreated, the decay begins to spread down towards the root damaging the internal nerve of the tooth. This causes severe pain and possible infection and at this point, a root canal must be done. That is why it is important to treat the decaying tooth at the early stages, preventing the force of deeper treatments. Composite fillings are tinted to match the shade of your tooth enamel so your restored tooth will look white and natural after the filling is placed.