Cosmetic bonding describes the bonding of a tooth-coloured resin to an existing tooth, with the objective of repairing defects. The resin is shaped to mimic the original tooth and involves a minimum alteration to the original tooth enamel. Tooth bonding is generally used to fix smaller defects in one or two teeth, or to change the shape of a tooth, and the treatment is usually completed in a single visit. The treatment is typically reversible, virtually painless, and will usually last for many years. Veneers are often recommended for more extensive smile makeovers.