A veneer is like a false fingernail, it is used to cover the tooth surface in order to mask any defects in colour, shape or size. They are not recommended as an alternative to orthodontic treatment because they only serve to mask problems and are considered to be invasive. The longevity of a veneer is around 10 years and you would need to replace them due to deterioration of the material. To place a veneer on a tooth the dentist might have to drill the tooth surface to reduce its overall thickness, however this is not necessary in every case. Special care is taken to match the colour and translucency of your other teeth for the most natural result.
There are two main types of veneers, porcelain and composite. Porcelain veneers are wafer thin pieces of ceramic material that are stuck to the front side of the teeth. Their placement usually involves some amount of tooth reduction.