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