Cosmetic dentistry is generally used to refer to any dental work that improves the appearance (though not necessarily the functionality) of teeth, gums and/or bite. It primarily focuses on improvement in dental aesthetics in color, position, shape, size, alignment and overall smile appearance. Many dentists refer to themselves as "cosmetic dentists" regardless of their specific education, specialty, training, and experience in this field. This has been considered unethical with a predominant objective of marketing to patients. The American Dental Association does not recognize cosmetic dentistry as a formal specialty area of dentistry. However, there are still dentists that promote themselves as cosmetic dentists. There are primarily two dental specialties that predominantly focus on dental aesthetics. They are: Prosthodontics and Orthodontics Cosmetic dentistry may involve: the addition of a dental material to teeth or gums – examples: bonding, porcelain veneers (laminates), crowns (caps), gum grafts the removal of tooth structure or gums – examples: enameloplasty, gingivectomy neither adding nor removing dental materials, tooth structure, or gums – examples: teeth whitening (bleaching), laser whitening, gum depigmentation straightening of teeth accompanied by improvement in appearance of face – orthodontics veneers, dental laminates - conservative scaling Whitening, or "tooth bleaching", is the most common cosmetic dental procedure. Whitening is a safe process that is effective for most patients. Multiple whitening options are available, including over the counter products such as Crest Whitestrips, as well as dentist-supervised methods such as in-office treatments or at-home treatments involving trays with a peroxide gel. Laser whitening is a teeth whitening technique in which gums are covered with a rubber dam and a bleaching chemical is applied on the teeth. A beam of argon laser, which is intended to accelerate the process of bleaching, is then projected upon the teeth. This laser activates the bleaching chemical and lightens the teeth color.