Procedures and Patient Management Flashcards
Explain the screening procedure:
- introduce self and check name and DOB
- explain what screening is for (checking suitable for work, can’t guarantee work with the school, longer waiting times, longer procedures but good standard and checked by tutor)
- go through covid questions
- suitability top 4 questions and any time any day
- medical history form
- let patient read consent
- sign off by tutor
- extra oral and intra-oral exam
- findings and finish suitability form
- place referal
- write up notes
How do we numb the UR3 - full procedure
Infiltration with a 27 guage 0.4mm diameter 19mm needle and 2.2ml catrage of 2 % lidocaine at 1: 80,000 adrenaline.
- provide 5% topical lidocaine ointment if nervous
- retract lip with mirror to see frenal attachment taut
- tell patient to look away and there will be a sharp scratch
- go in at 45 degree angle toward apex of tooth
- until hit bone
- aspirate to ensure not in blood vessel
- release 1/2-2/3 cartraige
- repeat on palatal aspect
- wait a few minutes and question about numbness
before any operative treatment is given, what do we do?
PREVENTION
- OHI
- PMPR
- get oral hygiene under control with duraphat, mouthwash, high fluoride toothpaste
why is it a negative thing that we remove dentine during RCT?
Dentine can distribute mechanical load laterally within a tooth (e.g. premolar) however if the singular root is canaled and filled, this reduces proprioception and mechanical integrity so under occlusal force, the restoration/tooth tissue can fracture.
What parts of the RCT process cause the dentine have less integrity and fracture strength?
- dentine is removed so less
- NaOCl for dissolution of superficial (canal wall) collagen (organic material)–
- Eugenol – component of sealer for the finished root canal and increases dentine microhardness, makes dentine more brittle
- EDTA – dissolution of superficial (canal wall) calcium hydroxyapatite (inorganic material).
why is partial caries removal preferred over complete caries removal?
- less chance of pulpal exposure
- less tooth tissue lost, more tooth integrity
- affected dentine can remineralize
why do we use cooled burrs?
- irreversible structural damage occurs to dentine over 70 degrees
- burs generate lots of heat by them self
- dentine is very sensitive and burning heat can be felt by patient
- pulp will lay down tertiary dentine reducing the pulp chamber
what is RDT? why is ti important
remaining dentine thickness. determines how the pulp reacts, vitality of tooth and integrity of tooth
what is the difference in how we treat fully necrosed pulp and partially infected pulp?
fully necrosis = pulpectomy removing all of the pulp and RCt
partial necrosis = partial pulpectomy removing the necrosis and re-establishing healthy pulp
what is indirect pulp capping?
where pulp has not been exposed but as a precaution we place GIC or capping material close to base and then cover with composite/amalgam to protect the pulp.
what is direct pulp capping?
when we have breached the pulp chamber and we try to stimulate dentine bridge formation to close exposure as pulp has no epithelium.
explain pulp capping procedure
- rubber dam
- remove blood clot
- Establish Haemostasis and clean with Chlorhexidine, Sodium hypochlorite or Saline.
- gently place capping agent (dycal, CaOH) not applying pressure of pulp dispalced and necrosis
- cover in GIC or hard cement or CaOH will dissolve
- seal with permanent restoration
- review in 1 week for symptoms
- review in 6 months to check dentine bridging and tertiary dentine with no pain
what is the main factor in pulp cap survival rate?
if the cap was placed within 2 days of exposure
when would we provide a pulp cap or RCT with pulp exposure?
pulp cap when mechanical exposure due to operator, immediate
RCT if carious pulpal exposure as very low prognosis
what is a pulpotomy and pulpectomy and when are they done
pulpotomy = coronal pulp removed as emergency treatment to then be capped and finished as pulpectomy at later date OR in deciduous teeth pulpectomy = full pulp removal for RCT
what is the EWL?
EWL is the radiographic length from the highest point of the tooth to the tip of the root. We then minus 1mm from this.
what pre-op checks do we take before PD work
any active caries? any current restorations? fractures? any tooth wear? rotation/inclination? Pulp vitality and Sensibility level of coronal damage; damage extending into the root; viability of restoration after root canal treatment
what are the stages to RCT?
access cavity pulpal chamber removal coronal 2/3 cavity apical 1/3 cavity step back apical gauging dryiing obturation
explain enamel access of an anterior teeth
- anaesthetise and rubber dam and seal with oraseal
- with a round diamond bur, drill in small motions a triangle (with single point apical) on palatal surface into the dentine
- expose pulp and now use round rose head bur to clear the chamber
- use upward motions to break roof of pulpal chamber
- use endodontic explorer to identify the pulp canals
- Use lateral movements of a gates glidden bur or endo-Z bur to flare and finish the walls of the access cavity. this forms a flared entrance to the canal
what do we use to irrigate the canals in RCT? why do we do this?
NaOCl - bleach, antimicrobial
EDTA - removes smear layer
To kill bacteria, remove smear layer, flush out debris and bacteria
why do we need such a tight seal of rubber dam for RCT?
to prevent any cross infection from the oral cavity into the pulp or pulpal bacteria into the oral cavity
also to prevent bleach NaClO getting into the mouth or digestive system
even when the pulp has been removed, how may pain still occur after RCT if the patient is not anaesthetised?
water potential of the sealant causes hydrostatic pressure at the apex or lateral canals can cause significant pain
why is single tooth isolation better than multitooth isolation for RCT?
recues chances of leakage
if a file is struggling to fit down a canal, what can we use to help?
canal lubricant like glyde
why is straight line access important?
so that when working on root preparation the files bend as little as possible. This reduces chances of apical perforations, zipping, and file fractures
explain the coronal 2/3 preperation
Find the 1/3 mark up from the apex is roughly ¼ up of the whole tooth so find 3/4 of the working length and round UP 15.75 = 16mm.
Prepare up to 16mm with size 30 K file to open far enough for gates gliddens. Irrigate with NaHCl very slowly so it doesn’t come out of the apex.
Use a size 4 gates glidden to 12mm, size 3 to 14mm and size 2 to 16mm and irrigate and use k file size 15 in-between each
Now place the largest k file that snuggly fits to the EWL, usually size 15, and take a EWL radiograph
If the apex is within 1mm of the EWL then this is now the AWL. If the EWL is more than 1mm from the EWL then adjust the EWL and retake the radiograph so the AWL is 0.5mm from apex. Adjust coronal ⅔ accordingly. AWL = 23.5
explain the apical 1/3 RCT
Increase the AWL file (which was size 15) by two sizes to at least 25 so that there is enough space for Master GP and filling material.
Do this by working up the sizes e.g 15, 20, 25.
In-between each, irrigate and recapitulate with k file size 10. This gives us the master apical file master apical file (MAF - 25)
explain step back preperation in RCT
now we work backwards in increments of 1mm, increasing the k file size by 1 from the MAF We do this 5 times to meet the coronal ⅔ prep. 23.5mm = 25, 22.5mm = 30, 21.5mm = 35, 20.5mm= 40, 19.5mm =45
If this doesn’t meet the ⅔ coronal, adjust the gate’s glidden sizes to meet to give a correct taper
Irrigate and repiculate between each step with size 10 K file to AWL
explain apical guaging
Get the MAF (25) to AWL and pull. If there is resistance (pull back) this is correct.
Set the next size up (30) to AWL and press down, this should stop 1mm from the rubber stop. If this does not happen, adjust the MAF and step back.
how do we dry canal in preperation for obturation?
Use the 3 in 1 gently
cotton wool buds to dry the cavity as much as possible.
Now use paper points equal or smaller than MAF to fully dry the canal until they come out dry
explain obturation of RCT, excluding cut back
Get the master GP point (MGP - equal to MAF) and crimp to AWL.
Place it in the tooth. There should be resistance to ‘tug back’.
Take a master GP radiograph. Should be no voids and should go to AWL. If not, adjust.
Now mix sealant (2 equal pastes) and then coat the MGP in sealant and press it in. Use finger spreader with rubber stop 1mm from AWL to press against side with high lateral/apical force and then coat an accessory GP size B and press in to 1mm from AWL. Repeat this, stepping back 1mm each time.
When three GP points are in, take a mid obturation radiograph to ensure no voids.
Carry on using the finger spreader to make sure the canal is completely packed with GP.
Explain obturation cut back and how to finish the restorations
Cut off the top of the GP as close to the ECJ with heated excavators
Use a small rosehead to finish off.
Measure the ECJ on the outside of the tooth with rubber stop and then ensure this height is achieved on the inside.
Top with a ZnOE liner and then fill with a composite (with etch and bond)
explain how to give inter-treatment medication as a temporary filling for mid-RCT
Irrigate for 1 minute
Dry the canals and preperation
Place pea sized amounts of non setting CaOH onto a K file smaller than MAF and place as deep into the canal as possible.
Use increasing increments with the paste to fill up to the CEJ.
Don’t get any on the sides of the access cavity.
Press down with cotton wool and then take an x-ray to ensure full.
Place a sponge and temporary restoration on top.
Recall within 4 weeks.
in what circumstances can we not provide RCT
-rubber dam cannot be placed if crown is heavily carious
-caries below the bone
-very poor restorability/prognosis
-terrible oral hygeine
-presence of peripaical lesions
-
what is the aim of RCT
- prevent or cure apical periodontitis by eliminating source of infection
- stop pain for patient
why is gutta percha only used up to the CEJ
if it was within the crown, this would cause staining and be visible outside the tooth
why do we irrigate?
-remove debris
-dissolution of dentine walls to remove bacterial biofilm
-To clean the parts of the root canal system which are inaccessible (e.g: Lateral canals)
-To facilitate instrumentation and prevent root canal blockages by acting as a lubricant
Removal of debris
Lubrication of instruments
Antisepsis
Decomposition and removal of blood and tissues
Remove smear layer
why is obturation done in the root of a RCT tooth
- Completely seal all anatomical parts
- Prevent reinfection of the root canal system by denying access to oral bacteria
- Resolution of signs and symptoms of disease
- Restore the integrity of the tooth
what are some general outlines of an access cavity
smooth walls
tapered walls
no overhands/underhands
what probe and burs do we use for RCT
- DG 16 Endodontic explorer
- long shank rose heads to increase visability
- endo-Z burs or gates gliddens for tapering
what would happen if we leave some debris/bacteria in a RCt tooth
discolouration and re-infection
what is the crown down approach
where we remove all of the debris and bacteria/pulp from the crown pulpal chamber and then slowly move down the canals
if there is a lack of full length glide path in a root treated tooth, what can occur?
Ledge formation
Transportation of the apical foramen
Zip formation apically
Perforation
why do we stop 0.5mm away from the AWL?
- we want to prepare the RCT to the apical constriction not the foramen as it constricts and forms a good blockage to the peri-apex (so less SA of ‘forein’ filling material can be attacked by immune)
- if we break through the apex, over instrumentation can cause fractures which lead to lesions very hard to fix
if we use over instrumentation at the apex of a tooth, what may happen?
- Damage to the root apex and periapical tissues
- Extrusion of debris which may contain microorganisms, elements of necrotic pulp, and infected dentine chips
- The presence of excess root filling material in the PA tissue which may act as foreign matter and be attacked by the body causing a lesion
- irrigation with NaOCl may enter the periodontium which requires immediate MaxFax treatment
- zipping and translocation of apex
radiographic (2D) evidence of WL may not be enough. how else can we find the AWL?
tactical feedback with experience.
electronic apex locator
paper point (if it has blood on it, it is at the apex)
what is zipping/apical transportation and how does it happen/how do we prevent
zipping is connecting two apacies
apical transportation is perforating the lateral wall forming another apex on a bending root
causes by a poor glide path and not removing ledges
what must an irrigant be?
Antimicrobial Cheap Able to dissolve pulp tissue Able to remove the smear layer Easy to use Long shelf-life Compatible with dentine Tissue-friendly Substantive (remain in the root-canal for a sustained period) Non-corrosive for dental instruments Non-toxic
what is a smear layer and why is it important
an amorphous film of organic and inorganic material generated from instruments contacting the root canal walls. It ‘plugs’ the dentinal tubules and delays the penetration and effects of antimicrobials.
what is apical enlargement
when we enlarge the apex by 2 k file sizes to get the MAF
How do we avoid irritant getting into the periodontium?
inject very slowly
dont over-instrument the apex
work the irritant 2mm from apex
what percentage EDTA do we use and what is its main function
17%
Remove the smear layer (mineralised inorganic component)
Unable to dissolve organic matter
Should be used in conjunction with NaOCl
why must we remove the smear layer
smear layer harbours bacteria and nutrition for the bacteria
acts as a barrier for medications and prevents good seal/penetration of canal sealer
during RCT, what is the procedure for different irrigants?
use NaOCl throughout for disinfection and debris removal
when canal is open, use EDTA to remove smear layer for 1 minute
use NaOCl to disinfect again
what percent of root canaled teeth still harbour bacteria?
50%
What is inter-visit medication and what do we use for it
a medication filled into the canal between RCT steps to disinfect the canals and root
We use non-setting Ca(OH)2 with very high 12 pH
why do we obturate?
-Prevent coronal leakage of microorganisms or potential nutrients to support their growth
into the dead space of the root canal system
-Prevent periapical or periodontal fluids percolating into the root canals and feeding
microorganisms
-Entomb any residual microorganisms that have survived within the root canal system
following mechanical and chemical preparation
-Completely seal all anatomical portals of entry/exit to the root canal system
-Prevent reinfection the root canal system by denying access to oral bacteria
why would discolouration of the crown follow RCT?
- if root filing material is left above the CEJ
- by products produced by remnants of dead pulp that were not removed
- staining from coronal restoration e.g. if amalgam
what is tug back
when we place the master GP point in a tooths canal and when we pull, there is slight resistance showing the master GP is the correct size
what method do undergraduates use for obtruation
cold lateral condensation
why is inter visit medication important
to keep the root canals in a bacteriocidic environment in between the sections of treatment during an RCT
how do we complete intervisit medication
hypo Cal up to the CEJ
use ZnOE (cavit or cotosol) or a sponge but NOT cotton wool above
use GIC to temporarily seal the cavity
why is cavit used underneath GIC in inter visit medication
to provide support underneath the GIc on posterior teeth to rpevent collapse of the inter visit medication
what should we avoid when placing the CaOH for intervisit medication
pushing it down hard enough to breach the apex
getting it on the coronal cavity walls as it impedes the adherence of the GIC
why do some inter visit medications involve corticosteroids
to reduce the inflammation of the pulp/periodontium
why should we not overfill an RCT with GP points (past the CEJ) (2)
- difinitive leakage pathway for bacteria
- staining of the crown
what is to be expected after an RCT? How do we treat this? what do we advise against
residual pulpal/periodontal inflammation
pain common 2-3 days after, peaks at 5-7 days and lasts 10-12 days
analgesics NSAIDS, not steroids as these will not help
why is it a problem if we only fill 2/3 of the root in an RCT?
there is residual bacteria that will still cause inflammation e.g. abscess
what happens first 8 days post extraction in a healthy state
blood clot forms with lots of blood clot over the extraction site to prevent bleeding
neutrophils slowly move into the blood clot to form a protective barrier
granulation tissue forms at the base of the extraction socket and up to the blood clot
at ~8 days post extraction what begins to happen to an extraction socket
epithelium proliferates from either side of the socket (gingival epithelium) at the level of the granulation tissue neutrophil border to cover the socket
at 18 days post extraction what would we see in a healthy case
granulation tissue filling whole socket
epithelium covering the whole socket
woven bone forming either side of the base of the socket with osteoblasts
foci of chronic inflammatory cells e.g. lymphocytes under epithelium
would all granulation tissue in an extraction socket be turned into woven bone?
no, some becomes connective tissue to underlie the epithelium
2 months post extraction what would a histological slide of a socket look like
most socket filled with woven bone, very pink with high collagen
connective tissue underlying epithelium
scattered chronic inflammatory cells
3 months post extraction what would see histologically
cancellous bone formation
remodelling to remove ridgid edges
resorption of bone replaced with adipose - marrow space
a patient has recently had a tooth extracted and is complaining of a foul taste in mouth. What should we do and what are we likely to find. what is causing the foul taste?
take radiograph
bone fragment still within socket
pus leaking from abscess formation of inflammatory cells and necrotic tissue
what is good practice after extraction?
OHI
radiograph to ensure no remaining tooth/bone
Pack and suture
what risk factors increase risk of improper healing of extraction tooth sockets
smoker poor OHI MRONJ risk - bisphosphonates + steroids / IV bisphosphonates High exercise Radiation exposure
how do we avoid haemorrhage after extraction with antiplatelet users
usually fine if only on 1
if more than 1 ask haematologist
usually fine just pack and suture
how do we avoid haemorrhage after extraction with haemophilia or VWBD
give factor VIII and IX
Or desmopressin
what type of haemorrhage can occur after extraction and what causes them
primary: starts straight after extraction due to local factors or bleeding disorder
reactionary: within 48hrs of extraction ,exercise, heat, anaesthetic wearing off (we tell them not to drink alcohol, exercise or put heat on to prevent vasodilation)
secondary: approximately 1 week after surgery, due to infection (vascular response) after tonsils have been taken out this increases in chance
what post operation instructions do we give to prevent haemorrhage after extraction and why
don’t do vigorous exercise, drink alcohol or get warm 48 hours after extraction
prevents reactionary haemorrhage due to vasodilation and blood thinning
what do we do immediately after extraction
apply firm pressure with gauze and ask patient to bite down
compress socket
if someone is bleeding without clot what tests do we take
PT prothrombin time test APTT activated partial thrombinogen time test full blood count to check platelet count check for VWBF Check medication
how do we stop a bony bleed and a gingival bleed post extraction
bony - haemostatic pack the socket
gingival - suture
if stopping a bony bleed, what can we use to pack and absorbs clot?
Packing is done with surgicel or curicel which are packed into the socket and are resorbable oxidised cellulose which helps clot form.
We can also use gelatin sponges which absorbs up to 45 times their own weight in blood - pressure tamponades bleed.
what are gelatine sponges
sponges used for packing extraction sites that absorb 45x their own weight of blood
what is surgicel made from and when is it used
resorbable oxidised cellulose
helps form blood clot after extraction
what should we hear when opening a syringe/cartraige
snap
if not, it is not sterile so use new
what is primary intention
wound edges are opposed (brought together) and held in place by mechanical means (sutures). Can’t always do this as the underlying tissue e.g. glands, ducts and nerves will keep leaking so they have to be fixed first.
when can we do primary intention
tissue is clean
little loss of tissue
if blood vessels/nerves/glands are invovled
why is primary intention good
improves rapid wound healing
minimises scarring
Prevents infection
what is secondary intention
wounds left open and edges come together naturally and heal.
when do we do secondary intention and why
when there is little connective tissue
when the wound is large and lots of tissue lost as stitching would put a lot of pressure on the wound and cause more scarring
in most cases post-extraction, do we practice secondary or primary intention? when would we do the other
secondary
if bleeding a lot, we would do primary intention
what do we use to separate teeth during electric pulp testing
cellulose strip
how do we do a cold sensibility test
spray endofrost on a cotton wool bud
place on mid-labial surface
wait for positive response
test contralateral teeth
how do we do an electric pulp test
dry tooth and separate from other teeth with cellulose strip
apply conducting medium to electrode e.g. toothpaste
apply to flat surface on tooth and slowly increase voltage
record positive or negative
what number should we set the ‘change in stimulus’ for electric pulp testing
4 or 5
why would we get false positives during electric pulp testing (4)
if the patient is anxious
partially necrotic but still needs RCT
metal restorations conduct to adjacent teeth
inadequate isolation
why might we get false negatives during electric pulp testing
nerve damage due to trauma
sclerosed canals/pulp chambers due to reactionary dentine
how can post-extraction problems be classified (3)
local (haemorrage) or distant site (endocarditis)
minor (removal of alveolar bone) or major (haemorrage)
general (pain, swelling) or specific (loss of sensibility)
what is a oro-antral communication OAC and what is its most common cause
a passage created between the mouth and the MAS which is already connected to the nose
commonly caused by extraction of upper molars with partial involvement with the MAS
what are some signs and symptoms of OAC oro-antral communication
symptoms
drink water and it comes out of nose
failure to make oral seal
air passes into mouth when mouth closed
signs small eggshell bone on extracted root void into sinus antral lining visible/prolapse bubbles in socket
what are two outcomes of oro-antral communications
if small perforation: with good POI, it will heal over
if large perforation: epithelial covering forms oro-antral fistula which needs removing
what is an oro-antral fistula
where a thin, weak epithelial covering covers a large oro-antral communication that needs removing
what POI should be given if we create a small oro-antral communication
don’t blow nose or sneeze
dont fly due to increased cabin pressure
avoid injury and dont swim
what can be prescribed for a patient with a small, healing oro-antral communication
decongestants e.g. epinepherine naal spray to releive blocked nose preventing need for blowing nose
anitbacterial like amoxicillin
what POI should be given in regards to swelling with posterior extractions
pain and swelling is common and normal
however if a swelling begins to disrupt airway or passage of food, call immediately
why might burnt lip occur during procedures
instrument heating
double gloving prevents sharps injuries but reduces operators sensitivity to heat
pt under anaesthetic or sedation so dont stop when pain
how long does it take for dry socket to form post XLA
48 hours
which extractions definitely require radiographs, why and what other imaging can be done
molar extractions
upper molars close to MAS
lower molars (especially 8s) close proximity to IAN
check nerve proximity with CT scan
what is the maximum weight for dental chairs
20 stone - 140kg
what might be found on an x-ray that can complicate extractions (5)
within MAS near nerve - IAN root filled tooth with less integrity heavily carious tooth recurrent caries long, curved root ankylosis
what are the implications of possibly extracting a stand alone upper 7
possibly within the MAS
MAS may have moved into root space of 6 or 8 by pneumatization making MAS in close proximity
what are 3 phases of failed socket management
Anticipatory phase: prevent, POI, make refferal, xrays/CT
Immediate phase: sutures, use instruments to removed fractures
Palliate phase: treat wound, dressings, CHX M/W, antibiotic prophylaxis
what is a luxator
sharp, relatively straight ended instrument used to break sharpeys fibres in PDL to loosen tooth
what is a cowhorn used for
extraction of lower molars, gets under the furcation to ply up
what are eagle-beak forceps used for
removal of lower molar by initiating the furcation
what tools can we use to help removal of partially removed teeth as immediate phase of extraction
luxators to break PDL to loosen
cowhorn or eagle beak forceps to get under furcation and bring out roots
what is the trans-alveolar surgical removal of teeth
used to remove roots that fracture during extraction
flap up the buccal muco-periosteal flap
use bur to remove, section, sever, elevate root
replace flap and suture
what is surgical removal of a fractured root
trans-alveolar surgery
how can we surgically cover an oro-antral communication (3 ways)
Buccal advancement flap: we raise buccal flap, undermine periosteum, pull mucosa over the gap and seal with water tight seal. This may be very thin.
Can use buccal fat pad of cheek to form bilayer closer on top of communication and mucosa over this. Done for very thin buccal mucosa.
Palatal rotational flap using flap from palatal side with palatal artery to maintain vitality, this is keratinized and thicker to form a thicker, stronger seal over communication.
what is the advantage of using palatal rotational flap vs a buccal advancement flap
palatal mucosa is keratinized so is stronger and more resistant
palatal artery involvement leads to durability and vitality
when would we use a buccal fat pad for covering a oro-antral communication
used when the buccal advancement flap is too thin so buccal fat pad used to form a bilayer
what part of the mandible can came off with an upper wisdom tooth
maxillary tuberosity - end of the alveolar process of the maxilla
what are signs of the maxillary tuberosity being removed with an upper molar
large chunk of bone with tooth
indirect oro-antral communication
tearing of palatal mucosa
mobility of adjacent teeth
what is an endoscopy
using small wires and cameras to surgically remove things
what is the duty of candour
duty to tell the truth to our patients when something goes wrong and be patient centered and work for them
how do we refer an extraction problem
by letter if non-urgent e.g. bone removed with tooth
by fax/phone if urgent to local MAXFAX surgery if urgent e.g. haemorrage
explain a plaque score test breifly
rub vasaline on lips to stop staining
give plaque disclosing
rinse to remove stained salivary proteins
mark gingival plaque scores (not coronal)
find score
how m much force do we use for BPE
20-25g force - enough to blanch hand but not hurt
what probes can we use for BPE and 6PPC
williams probe (small increments of silver and black)
WHO BPE probe with incrementas at 3.5mm, 5.5mm and so on
UCF with only silver 1mm increments
how is mobility measured
grade I (1mm movement), grade II (2mm of movement) or grade III (more than 3mm movement)
how do we stage furcation involvmenet
Grade I = can see furcation but probe doesn’t go through. Grade II = probe goes through upto 3mm but not all the way and Grade III = through and through.
what is the procedure for syncope
fainting
lay down with feet raised
glucose drink
cold compress on head
what are the different coarsness of prophy pastes used for
very coarse - removal of plaque and heavily stained enamel
coarse - plaque and stained enamel
fine - plaque and light discoloration
extra fine - finishing restorations, removal of plaque dislcosing
