NiTi or Stainless Steel wires are coated with Teflon/5META/Tooth colored epoxy resins. 4 Coating products are synthetic resin or plastic resins including epoxy resins.three Coating increases esthetics and decreases friction but There are many shortcomings also. Stainless Steel: Orthodontists started utilizing this type of steel for wires within the 1930s. https://roundnitiwires69134.ampedpages.com/round-steel-wire-things-to-know-before-you-buy-61246484