Coiled Springs for Use in Orthodontics

ANSI/ADA Standard No. 159 Executive Summary

What is ANSI/ADA Standard No. 159 about?

This standard applies to coiled springs for use in orthodontic appliances. It gives details of test methods to compare their physical and mechanical properties, the test methods by which they can be determined, as well as packaging and labeling requirements.

What are the requirements I should know for coiled springs?

The manufacturer shall declare the following physical and mechanical properties which, when tested in accordance with the test methods described in the standard, shall be within the ranges stated by the manufacturer:

Dimension   
Inner diameter, outer diameter, unloaded spring length, total spring length.

Mechanical properties    
Elastic behavior during unloading: maximum extension, maximum compression, spring load of the maximum extension or compression.

Chemical composition   
The range of composition of the alloy shall include all elements present at concentrations of 0.1% by mass or greater, and the mass fraction of any hazardous elements. Hazardous elements are designated as cadmium beryllium, lead and nickel.

What's the bottom line?

ANSI/ADA Standard No. 159 specifies the information that should be provided by manufacturers and suppliers to assist clinicians in comparing coiled springs. It provides the laboratory test methods to determine if the product meets the requirements for the amounts stated on the packaging and labeling.