ortho 4 zoom notes Flashcards
what is used to bring buccally placed canines back into position
- buccal canine retractor
why d you use a buccal canine retractor instead of a palatal finger spring for buccally placed canine
- finger palatal spring would only pull back and not into line
why is there tubing on a buccal canine retractor
- make it more rigid as otherwise it can be easily distorted
why do you only move the canines initially and not also fix the overjet as well
- moving anymore than just the canines would affect the anchorage
when are flat anterior bite planes used
- only ever used on the correction of overbites
why must you add the extra 3mm onto the FABP
- don’t want lower teeth getting trapped behind the bite plane
- adding on 3 stops them getting trapped
- prevents lower incisors becoming retroinclined
what is the dimensions of the FABP
- size of OJ + 3mm
why do lowers come up to meet uppers rather than uppers moving down
- uppers can’t move down as they are held in place by the appliance
what does the FABP do
- opens up space between the posterior teeth to allow the lowers to move up to meet uppers
how do Adam’s claps work
- applies the principles of either using or blocking undercuts
- part engages the undercut and this is how we get retention
- comes interdentally between the 5 and 6, and the 6 and 7
what does the bridge of the Adam’s clasp do
- keeps the buccal aspect away
- keeps cheek away
- gives patient area to go in and remove appliance
which part of Adam’s claps engage undercut
- arrowhead
which part of the Adam’s claps goes interdentally
- flyover
what is the leg of the Adam’s clasp
- goes down into palatal region
- needs to be gap between the leg and the palate to allow for the acrylic
- needs to be a gap of about 1mm between wire work and palate to allow for space for baseplate
what is the tag of the Adam’s clas
- gives some mechanical retention to stop component sliding out of acrylic
- because SS is so smooth, need to put this on to lock/grip it in place to stop it getting pulled out acrylic
which part of the Adam’s clasp needs adjusted first
- adjust flyover first before the arrowhead
- if did arrowhead first, then it would move again anyway when you try to adjust the flyover
what happens if the flyover is in the wrong position
- prop occlusion open
- metal fatigue = from biting on it until it reaches a point where it can fracture
- gum stripper = makes arrowhead irritate the gingiva
- can change shape of wire = can become non-functional
why do we fix the flyover before the arrowhead
- if fix arrowhead first, can then move again once fix flyover
what is the aim of the palatal finger spring
- move a tooth straight back
what does the coil of a palatal finger spring do
- where the force is exerted from
how does the coil of a palatal finger spring work
- works by uncoiling = this is how it moves the tooth
- wind wires up in coil
- want it to uncoil over a period of time which moves the tooth
what does the active arm of the palatal finger sprig do
- way in which the force is applied
- comes halfway around the canine
- only point where it applies the force is the corner of the canine tooth
why is the active arm of the palatal finger spring wrapped round the canine
- if only goes to the corner (where force is exerted), tooth could start to rotate because force coming from an angle
- so, we hug tooth with active arm to keep it going in correct orientation
what does the guard wire of the palatal finger spring do
- palatal spring will slide along the guard without interfering the palate
- allows active arm to move without traumatising soft tissue or being impinged by it