Dear Jenny:

It is very nice of you to provide the link.  Can you do more?  In fact I have posted it, under ortho, NPE.  The advantage is that you do not have to type.  But we still have to read by heart and put it to action.  I thought that you could learn more by forcing yourself to type.  It appears that it does not work for you or Suniti.

She is not too young for this.

Primary dentition: 1 to 2 months or less. 2 months retention.

Mixed dentition: 2 to 3 months depending on severity. 2 months retention.

Young adults: Usually 3 months. 2 months retention.

Adults: Depends on age:

Up to 5+ months. 3 months retention.