The development and testing of a new NiTi-SE-steel uprighting spring

Abstract

The uprighting spring presented here consists of a combination of superelastic material which is connected with a steel were by means of a crimped connector. Pseudo-elastic areas of such a spring can be used well by combining superelastic material with steel. The uprighting spring presented here yields the following advantages: 1. The uprighting moment of the molar is between 10 and 20 N with a 40 degree tipping of molar.2. The uprighting springs exhibit a large plateau in the area of 8 to 15 Nmm depending on a bending-in of an alpha-bend. 3. An intrusive force of approximately 0.5 to 1.0 N can be produced by varying the alpha-bend. The preformed uprighting spring in combination with a cross tube can be affixed without any problems, because only the alpha-activation must be bent in. 5. Practically, a reactivation during uprighting is not required. 6. An enlargement of the alpha-moment to produce an intrusive force makes great demands on the anchoring element. For this reason, one must check in each individual case, if an anchoring segment displays the required stability. 7. By lengthening the SE material at the crimped connector, the alpha and beta-moments become smaller, as does the intrusive (extrusive) force applied to molars.