What is a filling, and when do you need one?
A filling repairs a tooth that decay has hollowed out. The softened, infected part is removed and the space rebuilt, so the tooth is sealed and can take chewing again. We use tooth-coloured composite, bonded to the tooth and set with a curing light, rather than silver amalgam: it matches the tooth, needs less healthy enamel cut away to hold it, and is finished in one appointment.
The signs of a cavity are a twinge with something sweet or cold, food packing into the same spot, a rough edge your tongue keeps finding, or a dark line between two teeth. Plenty of cavities give no warning at all and turn up only on a check-up or an X-ray. Caught early, decay costs you a filling. Left alone, it reaches the nerve and the answer becomes a root canal.