Intro to lab teaching Flashcards
active appliance
move dentition to help fix malocclusion
early intervention
more successful and less invasive generally
components made of
stainless steel
properties of stainless steel (7)
- Biocompatible
- Noncorrosive
- Ductile
- Manipulated
- Solder without impairing properties
- Elasticity – spring back – can be placed in and out of mouth without fracturing
- Relatively expensive
stainless steel made of
Main constituent Iron
- mixed with small amount carbon (but corrosive)
Chromium (prevent corrosion)
Nickle (prevent corrosion) – can be nickle free if allergic
Titanium (adds to strength)
orthodontics compared to prosthodontics
orthodontics move teeth
whilst prosthodontics fills gaps
3 aims of orthodontics
- function
- aesthetics
- stable occlusion
4 parts of URA design sheet
aim
Active component
Retentive
Anchorage
Base plate
orthodontic study models
Angled base stone
- Trimmed so that when put teeth together go into exact centric occlusion – stays when turning hands free on table so can view 360
Reduces need for articulators and keep hands free
why are not all study models orthodontic study models
time consuming as very specialised - so not done universally
use of study models (10)
- see dentition when pt not there
- record to compare - pre and post Tx
- legally keep them on conclusion of teethment - record keeping, medical legal, prove that you did what you said
- diagnostic
- treatment plan
- design removable appliance - build on working cast not master cast in case of breakage
- pt motivators
- teaching
- retrospective studies
- forensics
PAR
Peer Assessment Rating - numerical way of measuring malocclusion
- Overjet – horizontal - speech, trauma, biting, incompetent lips (gap between so no oral seal = dry mouth), lip trap
- Overbite – vertical (upper incisor edge comes further down)
- Cross bite – some teeth behind and some in front – can get anterior and posterior ones
- Midline shift – displacement of maxilla and mandible on horizontal axis
Higher the score the worse the malocclusionObjective way of scoring orthodontics
overjet
horizontal -
- speech, trauma, biting, incompetent lips (gap between so no oral seal = dry mouth), lip trap
overbite
- vertical (upper incisor edge comes further down)
cross bite
some teeth behind and some in front – can get anterior and posterior ones
midline shift
displacement of maxilla and mandible on horizontal axis
design removable orthodontic appliance on
working cast not master cast
in case of breakages
want study cast to be a true representation of pt
pros and warning of using cast as pt motivators
pros
- Can see the degree of issues – esp overjet
- Can cut teeth of and reset in wax in new treatment – potential end result
- Can take mid treatment to boost – pts, parents etc
- Need to complete treatment – as sometimes need to destabilise entire dentition to stabilise
- E.g. extract to realign – but don’t complete realign
- Need to complete treatment – as sometimes need to destabilise entire dentition to stabilise
BUT - Be careful not have unrealistic expectations – leave some small problems as always better to make better than what they expect than under achieve
*
why is orthodontics slow
not too much pressure exerted on teeth
- painful
- rupture PDL
- cut off blood supply and necrosis of teeth
its a long process for bone to reconstruct - adsorption and deposition
how many teeth moved at one
1 or 2 with removable appliance
move teeth in sequence as cannot move simultaneously
what is needed post ortho treatment
Retainer Post treatment
- Teeth will relapse naturally if not maintained in space
- Little pressure to maintain teeth in correct place
drawback of study casts for orthodontics
good crown, soft tissue representation
Not seeing bone levels or length of roots
- roots need repositioned as well
- Cannot have roots crashing together
- resorb or cut off blood supply -> necrosis
- Cannot have roots crashing together
how to manipulate wire
with pliers
2 types of plier
adams No64 universal wire pliers (Adams Pliers)
No65 coil formers
Adam’s pliers
Adams No64 Universal Wires Pliers (Adams pliers)
Pyramid shaped beaks
£212 a pair
Tungsten
No65 coil formers
Narrower longer beak
Round one side flat one the other (bird beak)
Mons Cutter
Wire cutters – dangerous – wire hard can ping
- Point down and away from face as cut wire at pace – so can’t ping around lab
wire bending
Pliers go in dominant hand and hold rock solid – vice
- Manipulate the wire around the pliers
Need to straighten the curve
- Grip wire in pliers in dominant hand and counteract it
Graphite pencil mark where bend
- Pliers on dot
- Grip pliers and push wire away from you to get into shape then adjust
- Always push away from you – safer
Hold onto tail end as sharp and don’t want to ping
normal thickness of wire used in bending
0.7mm HSSW
HSSW
hard stainless steel wire
