Principles of exodontia 1 Flashcards
AIMS
indications for extraction?
- Unrestorable teeth
- most likely due to caries - Periodontal disease
- teeth w/ grade III mobility (virtually no bone support for tooth) - Pericoronitis
- effects partially erupted teeth (usu wisdom), food getting stuck under gum surrounding tooth, causes
localised inflam - Associated pathology (e.g. cysts, tumour)
- Orthodontics
- Trauma
- Interfere with construction of a prosthesis
- Tooth within fracture line
- Teeth in a fracture line
- Abnormal/ supplemental teeth
- Impeding eruption of other tooth
( eg deciduous teeth that aren’t falling out) - Financial / phobia
Consent
what factors to consider when deciding if the extraction is safe to perform?
- Aware of medical history?
- Contra-indications?
- Know limitations (surgeons capabilities) REFER??
Factors that affect difficulty of extraction
- Tooth
- Supporting structures
- Proximity to adjacent structures
- Access
what tooth factors do we look at while deciding to extract tooth?
What supporting structures do we look at when deciding to extract?
What structures in close proximity to the tooth requiring extraction do we need to look at before extracting?
What access factors do we need to look at before extracting teeth?
Planning before extraction is very important and ensuring you have all the required equipment!
- in oral surgery department will have this equipment for extractions
- what are the required pieces of equipment?r
Assessment for exodontia includes?
What are the 2 main methods/types of extraction?
THIS LECTURE LOOKS AT ROUTINE EXTRACTION (using elevation, luxation + forcep extraction)
NEXT LECTURE (EXODONTIA PART 2) LOOKS AT SURGICAL APPROACH
Overview mechanisms of routine extraction?
PATH OF REMOVAL
1
Path of removal of tooth is determined by?
2
Routine extraction path of removal determined by?
3
Surgical extraction path of removal determined by?
– Morphology of root
(curvature, shape, n.o roots)
– Impaction
(Level + position of bone, adjacent tooth)
Main instrument used in routine tooth extraction?
Forceps
Look a bit like pliers
What is each part of forceps called and how does it help with tooth extraction?
What does blade do
HANDLE
- work by lever principle
- long handle attached to blade
BLADE
- Holds onto tooth during removal
- in long axis of handle (upper teeth) or right angles to handle (lower teeth)
- Wedged shaped blades – dilate socket break PDL
- ‘Beak to cheek” – upper molar forceps
How does positioning of the blade with the handle effects it’s function?
- Blades in long axis of handle = REMOVE UPPER TEETH
- Blade in right angles to handle= REMOVE LOWER TEETH
How to hold forceps?
- put index finger between handles so they can open forceps
- engage tooth at CEJ (effectively coronal portion of root surface of tooth)
- once engaged tooth removed index finger from between handles so can hold handle tightly (to provide apical pressure needed to remove tooth)
- hand positioning on upper and lower forceps slightly different
HARD TO SEE IN LECTURE, WILL SEE ON CLINICS BETTER
1
What do the blades need to fit for effective extraction?
2
What do you do if the blade doesn’t fit this?
What does blade need to have and which part of tooth
4 main methods of routine tooth extraction?
What do forceps do to help with tooth removal?
What should forcep engage on the tooth
1 Sever PDL
2 dilate bony socket
(Coronally)
EXTRA
- help do this as sat on CEJ of root and blade will sit into PDL space and damage PDL corronally, hence sever
- and with wedge effect will dilate PDL spaced socket coronally
- as engage tooth properly, are able to move tooth laterally to dilate socket as well
Why are teeth delivered buccally durning routine tooth extraction?
Forcep extraction steps
- APPLICATION
Separate coronal PDL from tooth:
- Probe around the gingival margin of tooth (also tests anaesthesia)
- open handle of forceps using index finger
- place blades on CEJ (coronal portion of root) + engage
- tips of blade should be hidden below gingival cuff (should slide blade down to this area with minimal soft tissue damage)
- Align forcep beaks along long axis of tooth
- Push forceps apically along root surface (cowhorns to engage furcation)
- Engage root surface (grip root) with beaks by closing forceps
- squeeze hard on forcep handle
- APICAL FORCE
Maintain apical pressure throughout tooth extraction :
- put a lot of pressure down the long axis of the tooth
- apical positioning of tooth will dilate the socket
3 LATERAL MOVEMENT
Expansion of socket
- buccal & palatal/lingual movement
- Figure of ‘8’/ circular movement
- Maintaining apical pressure throughout
- ROTATIONAL MOVEMENT
Tear soft tissue attachment (apical granuloma/ gingival mucosa)
- Removal of circular, single rooted teeth (upper incisors, lower
premolars)
- DELIVERY
* After tooth is mobilised traction forces remove the tooth from the socket
Purpose of:
1
application of blades below gingival margin?
2
lateral movement?
3
rotational movement?
1
- Separate coronal PDL from tooth
- grip tooth
2
expand socket
3
tear soft tissue attachment
why does apical pressure need to be maintained throughout whole extraction of tooth?
Apical force:
* Prevents beaks sliding off root
* Expands socket by positioning coronal, wider root apically
* Centre of rotation of tooth displaced apically to prevent tooth fracture
* Alters angle of force on roots
how does centre of rotation effect extraction?
a
- optimum centre of rotation on root and how to ensure this?
b
what may affect the centre of rotation negatively and why might the root break?
- centre of rotation effects the risk of the root breaking during extraction
why is it important to dilate socket buccally and lingually + palatally
If only buccal force: then below in pic + likely to get root fracture in multi rooted teeth
1
what is apical and lateral pressure in multi rooted teeth?
2
why is apical + lateral pressure important while remove multirooted teeth?
What does LATERAL MOVEMENT cause
1
what is the right amount of pressure during extraction?
2
what happens if you apply excessive force
3
what happens if you apply too little force
4
What does lateral excursion allow?
Which direction is this done ?
5
Which direction will tooth move in?
What type of movements needed
LOWER COWHORNS
1
what are they?
2
what do they engage?
3
where to position?
4
type of movement used to extract tooth
UPPER COWHORNS
1
Where do they grip tooth
2
what type of teeth are these useful for?
are these teeth held correctly by the forceps? are they upper or lower teeth removal?
are these teeth held correctly by the forceps? are they upper or lower teeth removal?
what is this forcep called and how is it grabbing the tooth
are these teeth held correctly by the forceps? are they upper or lower teeth removal?
why is chair positioning important?
- can help tooth come out easier
- if incorrectly positioned can hinder extraction
EXTRACTION POSITIONING
1
MANDIBULAR Vs MAXILLARY EXTRACTION
- chair position
- chair height
2
ANTERIOR Vs POSTERIOR
- chair height
3
MANDIBULAR Vs MAXILLARY EXTRACTION
- head position
1
MANDIBULAR Vs MAXILLARY EXTRACTION
- want patient more upright than maxillary
- maxillary more reclined
- maxillary want chair higher compared to mandibular
2
ANTERIOR Vs POSTERIOR
- anterior want patient generally upright as access isn’t that difficult
- posterior lie patient more flat for better access
3
MANDIBULAR Vs MAXILLARY EXTRACTION
* Mandibular extraction - chin down
* Maxillary extraction – chin up
(WANT TO SEE OCCLUSAL SURFACES OF TOOTH
what to do with other hand during tooth extraction?
1 SUPPORTING HAND
*Support the jaw - counteract force from forceps/ elevators to stabilize jaw
- support alveolar bone
*Finger rest
2 RETRACTION OF SOFT TISSUE
*Thumb and forefinger either side of arch adjacent to tooth
*Holds retractor - to see surgical sight
3 FEEL ADJACENT TOOTH
*Check adjacent tooth not mobilising during extraction/ elevation
- if mobilising hen need to change method of extraction otherwise adjacent mobile tooth may also come out
what do elevators do?
sever PDL + can help dilate socket
ELEVATORS
position of elevators?
What is the fulcrum ?
What happens if you use the incorrect fulcrum?
3
movement while extracting?
- usu Positioned horizontally (90° to long axis tooth)
- usu Applied to root surface (mesial, buccal or distal) (positioned within PDL space
- Applied between root surface and alveolar crest (i.e. in PDL space).
- Alveolar crest (not adjacent tooth) provides fulcrum
2
* Accidental elevation against adjacent tooth can mobilise adjacent tooth and even extract it (especially if adjacent tooth is last standing)
3
* Rotation movement
* Elevate buccally not lingually due to access (due to access)
1
types of elevator?
2
structure / names of parts of equipment
3
what partengages tooth and what does it try to do?
3
blade engages tooth to try and mobilise
how to hold elevator?
- firm grasp of elevator
-forefinger up shaft to prevent slipping
how to position elevators?
black line = elevator positioned
are these positioned correctly?
why?
Elevator positioning and what does it do?
COUPLANDS
1
sizes?
what size should you use?
2
why is the long/ larger handle useful?
3
how to insert and where? (HINT MESIAL OR DISTAL)
4
how does it’s use help extraction?
How to know if you’re using the correct size elevator, how do you know if it’s too small or big?
WARWICK JAMES & CRYERS ELEVATORS
WARWICK JAMES & CRYERS ELEVATORS
What are these elevators useful for?
EXTRA - retained roots
- diagram = fractured L 2nd molar during removal
- has retained distal root
- cryers has been placed within mesial root socket to engage mesial surface of distal
- in order to do this sometimes interfercal bone needs to be nibbled away using cryers or warwick james (usu easy to do as quite soft)
- do this until instrument engages root surface
- then with rotation lifts root out of socket
can you remove wisdom teeth just using elevators
- should use elevators to mobilise molars
BUT not to remove tooth in its entirety
BECAUSE there’s no control and risk of tooth falling into patients throat
LUXATORS
1
Instrument structural difference to elevator
2
Where is it inserted and how
3
Function?
4
once tooth is out how do we check it’s been taken out in it’s entirety
TIPS
