Orthodontic arch wires

The method of making an orthodontic arch wire which comprises extruding metal wire to a desired transverse cross sectional shape;

• extruding a non-metallic material onto the metal wire of desired transverse cross sectional shape such that the non-metallic material covers a selected portion of the surface of the cross section of the metal less than the entire surface of the cross section thereby leaving exposed metal along another selected portion of the surface of the cross section;
• and forming the resulting product into the shape of an arch wire having concave and convex sides such that the exposed metal is along the concave side of the arch wire and the non-metallic material is along the convex side.

An improved orthodontic arch wire comprising a metallic part and a non-metallic part securely joined together, said two parts being arranged such that the metallic part faces teeth of the arch to which the arch wire is to be applied and the non-metallic part faces labially, said arch wire having an overall rectangular shape in transverse cross section in which the metallic part has a general T shape in which the base of the T faces labially and in which the non-metallic part is a U-shape which fits onto the labially projecting base of the T.

An improved orthodontic arch wire which comprises a metallic part and a non-metallic part securely joined together, said metallic part having outer and inner peripheral portions, said outer peripheral portion of the metallic part being disposed labially when the arch wire is applied to an arch, and said non-metallic part covering the entire outer peripheral portion of the metallic part, but leaving at least some of the inner peripheral portion exposed, said metallic and non-metallic parts having complementary transverse cross sections cooperatively forming the arc wire's cross section, but the transverse cross section of the non-metallic part by itself being different from the transverse cross section of the metallic part by itself.