Veneers are thin materials that are placed over a tooth, mainly for aesthetic purposes. Veneers can be composite or porcelain. A composite veneer usually takes one appointment, in which a preexisting veneer is placed over the tooth. Sometimes, they might be fabricated in the laboratory as well. Porcelain veneers need two sittings, in which a dental technician fabricates the veneer as per the required shape and size of the tooth. These usually last much longer than composite veneers and are the most common type.