Filling a tooth cavity is a common dental procedure that usually takes about an hour, though it can vary. The process involves cleaning out the decayed part of the tooth and filling it with a suitable material to prevent further decay and restore the tooth's function. The materials commonly used for fillings include composite resin, amalgam, gold, and glass ionomer. Composite resin is popular due to its strength and color match with natural teeth. Amalgam is durable and often used for back teeth. Gold fillings are long-lasting but more expensive, while glass ionomer releases fluoride, which helps protect the tooth. After the filling, you might experience some sensitivity, but it usually subsides within a day or so. The filling sets quickly, but complete healing might take a bit longer depending on the material used. Good dental hygiene can extend the life of your filling and prevent new cavities.