Effects of Nickel leaching from orthodontic appliances in the oral cavity: A review

Nickel (Ni)-containing alloys are present in a substantial number and wide range of appliances, auxiliaries, and utilities used in orthodontics and thus become an integral part of almost every routine orthodontic intervention. Orthodontic brackets, stainless steel archwires, stainless steel appliances, Nickel titanium wires are some of majorly used the Ni-containing alloy applications. Recent evidence has attributed carcinogenic, mutagenic, cytotoxic, and allergenic actions to Ni in various forms and compounds. This poses a threat to patients who are potentially allergic to Nickel. So, it is essential to bring into light the use of Nickel free substitutes.