This is an example of why we segment the arch wire distal to the canine before placing springs.

We have just removed the springs after over-correcting the first bicuspid to a half cusp Class III

The lower incisors are overly proclined. They have been tipped forward, leaving the roots in bone.

The bicuspid crown relapses forward by tipping, leaving the root apex Class I. The lower incisor relapses

back by tipping, leaving it proclined 3 degrees on average.

Eruption mechanics with Class II elastics or intrusive mechanics with Class II springs? Springs support upper incisor intrusion.

1. RME X 6 2. Xbow with springs 3 months 3. Full Braces for 13 months

_________________________________________________________________________

Impinging overbite. This is where you need Class II elastics. Class II springs cannot open the bite.

Neither can Class II elastics if the lower posteriors are not free to erupt. This is where a bite-turbo comes in.

1. Upper 2X6 and posterior bite openers, 2. 6 months Xbow followed by compensatory maxillary expansion,

now hold expansion and test Cl II correction for 5 months

Day of bite opener switch from posterior to anterior (bite-turbo) 5 months into full braces

______________posterior bite openers______________________________bite openers removed_______________

We begin most cases with posterior bite openers. They remove occlusal interferences to prevent debonds as well as

allowing lower alignment with the lightest forces

.

_____________________bite turbo placed_____________________Class II elastics to erupt lower molars and correct overjet from bite opening

 

This is where patient cooperation is needed. Class II springs cannot open the bite. Neither can Class II elastics

if the lower posteriors are not free to erupt. Over-correct to incisal edge to edge

.

9 months progress with full braces

12 months braces

3 years post deband