Bonding is the placement of a resin material on a tooth to repair a small chip, change the shape, appearance, or color of the tooth, or close small spaces. They are indicated in certain situations however they have advantages and disadvantages. They are done at chair side and the results are immediate. They are less expensive then porcelain veneers or crowns however the material is porous and can stain easily and requires replacement more often.
Read about porcelain veneers