A cleaver way to have torque and intrusion in segemntated orthodontics
Columbus Spring, the clever idea;
Columbus spring allows the operator to extend the cantilever arm of the force until the molars, this creates an ideal force system with respect to the center of rotation of the tooth facilitating the torque movement.
The use of high resilience TMA archwires and the springs of SS .018 made, lowerers the load-deflection ratio.
http://en.wikipedia.org/wiki/Cantilever_mechanics_(orthodontics)
Once engaged, the arch and spring compound produces a momentum of the force equal to 600 gr/mm on the incisors, with a vertical force as light as 20gr on molars. The long cantilever arm, in fact, creates the desired mechanical advantage...
...have you ever cracked a nut? This is the same idea
But how can you transmit the force onto the teeth?
"The rectangular shape of the slot is the one that is best suited to control tooth movement in three dimensions of space"
Stright Wire. Theoretical basis and practical applications - LF Andrews. 1989
....is that true?
Columbus Spring adopts a vertical insertion of the wire into the slot of the bracket.
...simply clever!
This allows you to
• Create a valid insertion of the wire in the third order, which eliminates the problem of archwire and bracket slot play.
The wire of .018 is almost full size engaged in the vertical slot .020 and this for a 2mm length of insertion. According to Kusy's formula the angle of play is less than 2 °;
• Being able to move each incisors independently from the others. This can be done from the early stages of treatment, eliminating the need to obtain a perfect alignment BEFORE you can begin the torque correction;
• Allows you to work with a bracket that has the dimension "height" allowing third order movements.
Columbus Spring is a registred medical device of Class IIa - non sterile.
It is produced with medical SS wires and the laser welding are tested and certified
Calumbus spring is designed, produced and assembled in ITALY.
