Endo

Question 1

Criteria for an access

Answer 1

Pulp chamber fully unroofed. no undercuts
no significant unnecessary loss of tooth tissue.
Instrument flight paths refined to allow straight-line entry to all canals.
sufficient retention for a secure temporary dressing

Question 2

Criteria and aims for canal prep (shaping and cleaning)

Answer 2

-Correct working length determined and maintained throughout preparation.
-Canal adequately flared
without evidence of over or under preparation.
-Apical enlargement appropriate with positive apical stops.
-Details of the preparation clearly recorded in notes.

-Shaping aims:
Open the canal space for mechanical debridement & optimal irrigant exchange (enlarging it and having straight line access)
Create a canal shape that will allow controlled filling of the canal system
-Cleaning aims:
Reduce the microbial load as far as possible
Remove as much pulp tissue/microbial substrate as possible (use sodium hypochlorite (5-5.25% NaOCl)

Question 3

Criteria for root canal filling

Answer 3

-Dense, homogenous root filling which extends to full working length. (within 2mm of root end)
-No over extension of gutta percha or
significant extrusion of sealer.
-Pulp chamber cleaned of excess filling material and ready for restoration or temporisation.

Aim o prevent reinfection of canals by sealing them off

Question 4

Criteria for fibre post and core build up

Answer 4

-Post is centred in canal and matches taper of preparation.
-Post meets GP in the middle third of canal with no void or interruption between post and GP.
-Root canal filling evident in apical third and intact.
-No voids
along the fibre post or core.
-good length
-roughened or serrated surface
-does not rotate in the canal

Question 5

what average length of most canals of lower teeth. what are the exceptions

Answer 5

-21mm
-lower 3s are 22.5mm
-lower 7s are 20mm

Question 6

how deep is it into the pulp for premolars and molars. Why might you not feel a drop for premolars

Answer 6

6mm
if bur is wider than chamber

Question 7

how deep is it into the pulp for upper incisors

Answer 7

3-4mm into pulp

Question 8

for lower 6, how many canals, what shape is the access

Answer 8

1 distal and 2 mesial canals
1mm central from ML and MB cusp tips with distal cusp opening in centre of tooth
(buccal cusps curve in)

Question 9

instruments used for access.

Answer 9

medium tapered diamond bur (8mm)
Endo Z or Batt bur for unroofing, that has no cutting end
long neck pin bur or goose-neck bur
perio or brialt probe to feel catches and that it is fully unroofed

Question 10

why don’t blow air directly down canal

Answer 10

surgical emphysema

Question 11

how pulp necrosis can occur

Answer 11

-Breakdown of protection due to caries, tooth wear, fracture, operative dentistry. Microbes enter pulp can infect and break down pulp tissue
-Trauma (mechanical, chemical, thermal): Trauma causing root to displace causing disruption of blood supply through root. Interpulpal space severed. Pulp becomes dead, but not infected yet. But any small fracture or exposure of tubules will cause infection of pulp

Question 12

treatment options for pulp infection

Answer 12

-host cannot eliminate the infection. And systemic antibiotics cannot eliminate the reservoir of infection
so…
-extraction
-pulpotomy (only if PAP not formed)
-pulpectomy/RCT

Question 13

why might we need to do RCT in healthy pulps

Answer 13

-the tooth cannot be restored without seriously endangering the pulp
-the tooth cannot be restored without
using the pulp chamber and canal system to retain the restoration
-there is intractable dentine hypersensitivity

Question 14

the stages of root canal treatment

Answer 14

-History, exam, special tests, Tx plan
-LA, control the environment (remove caries, temporary restoration between appts., dam.)
-Access cavity
-Shape & clean canals (need dam)
-Fill root canals
-Restore
-Review

Question 15

examples of unrestorable teeth with RCT

Answer 15

gross caries
advanced perio disease
vertical fracture

Question 16

why we remove the caries and give a temporary filling before RCT

Answer 16

-properly evaluate restorability
-eliminate a source of continued infection during treatment
-allow NaOCl to be contained during treatment
-minimise risk of unplanned tooth # during treatment.
-Remove unsupported cusps
-secure stable reference points for instruments

Question 17

benefits of a rubber dam

Answer 17

-prevents saliva (bacteria) entry to tooth
-protects airway & GIT from dropped instruments
-protects soft tissues so allows use of strong disinfectants
-retracts cheeks & tongue - better visibility
-improved patient comfort
-stops patient talking/rinsing - quicker!
-less likely to do wrong tooth
-moisture control for fillings

Question 18

steps in shaping and cleaning

Answer 18

1. Estimate canal length from average values & pre-op radiograph
2. Irrigate pulp chamber, gross pulp removal with broach
3. negotiate canals. Find zero reading then work out electronic working length (minus 0.5mm)- size 10
4. Create glide path with 10,15,20 files
5. Coronal flare with Shaper 1 and 2 (WL minus 5mm)
6. Confirm WL by taking x-ray with 15 or 20 file
7. Deep flare with reciprocal to WL, or S1, S2, F1
8. Shaping with 25,30,35 … at WL until apical stop at master file
   -Irrigate and 10 file to check latency after each file used

Technique=
Rotation: watch wind (anti-clockwise mainly)
Rasping: filing against the walls on outwards picking

Question 19

stages of filling a root canal. what is the technique called

Answer 19

-dry the canals with paper points
-get GP the size of the MF, measure the WL and crimp
-Master GP x-ray
-select correct spreader (red smallest, then green, then blue) by putting next to GP and should be 2mm short of WL
-select accessory GPs according to spreader selected
-coat master GP in sealer. place in canal. push spreader next to it. leave for 10s
-replace spreader with accessory GP
-spreader then accessory until fit no more (3-4 accessories)
-cut off then warm compaction

-cold lateral condensing technique- master GP, spreader to push it laterally and apically, accessory GP to replace spreader, spreader, next GP so on and so on. cut off GP at cervical line, remove excess, condense
-restore
do hardest canal first (MB for lower) then bend to side while do the other canals.

Question 20

aims of restoring the tooth after RCT. aim of review

Answer 20

to seal the canal from the mouth to restore treated tooth to function & aesthetics. to protect the tooth from fracture

to monitor healing and repair: did the treatment do its job?
Clinical exam: Has pain & swelling or sepsis disappeared? is it easy to eat
Radiographic exam 1 year after: Evidence of continued periapical health, or healing of apical periodontitis

Question 21

what is the probe called that can be used for locating the canals. How long is it

Answer 21

DG16
16mm

Question 22

Gaits gliddon bur sizes, lengths, use

Answer 22

either 16mm or 11mm
sizes 1-4
drill into the rubber to create frictional heat and drill out excess for allowing retention into canal entrances for core

Question 23

Standard ISO files: shank length, taper. What the number indicates

Answer 23

16mm of blades and 0.02nm/mm taper (2% taper)
-size indicates the diameter. size 35 is 0.35mm

Question 24

what are the 2 different materials of files and their properties

Answer 24

Stainless steel (size 10,15,20) = deforms. stiffer
Nickel-titanium (the rest) = has memory, flexible, springs back, bends around curved apices

Question 25

what settings are used on the special reciprocating motor. size and taper of reciprocating files (probs in exam)

Answer 25

waveone= CSU Reciproc= clinic instead of using S1, S2, F1 for deep flare -size 25, 8% taper in apical 3mm, 4% for remainder

Question 26

Purpose of irrigants. what is the ideal material. and other options

Answer 26

flushes debris from canal kills microorganisms dissolves organic matter lubricates instruments non-toxic/irritant, inexpensive -Sodium hypochlorite. it does all of the above but is an irritant -other options =chlorhexidine gluconate, saline

Question 27

antimicrobial dressing materials uses and materials and properties

Answer 27

Clean & disinfect canal between appointments kill microorganisms that leak in around temporary dressing -non-setting calcium hydroxide paste (pH 11/12, antibacterial for up to 3 months, dissolves organic debris) -chlorhexidine gel - broad spectrum antimicrobial -odonto paste - antimicrobial and anti-inflammatory

Question 28

purpose of sealer for filling canals. 3 materials used

Answer 28

Fills voids between points of gutta percha and ensures canal is well sealed. - ZOE -Resin (AH plus) -calcium silicate

Question 29

purpose of paper points. sizes

Answer 29

drying canals to prevent surgical emphysema if use air -checking for bleeding -size 30 or 60 -2% taper

Question 30

taper of GP

Answer 30

2%

Question 31

what is the resin called for sealing. its setting time

Answer 31

AH Plus Slow-setting (8hrs), Antimicrobial, widely used, best scientific documentation hydrophobic

Question 32

temporary filling materials for between appointments. which is better for load bearing sites. properties

Answer 32

Cotton wool barriers between canal and temporary material. Choose material depending on how long between appointment. Soft cement if couple days, GIC if few weeks -cavit = sets in contact with saliva, good in retentive, non loading-bearing sites, easy to remove. <7-10 days as will degrade. (a calcium sulphate cement) -sedanol = for non load bearing sites -GIC = expensive. Good for unretentive, load-bearing & aesthetic sites. 14+ days. Can be difficult to remove/distinguish from dentine as tooth coloured -IRM (ZOE with PMMA) = Stronger for load bearing sites (can last 1yr) 14-21 days

Question 33

what could happen if your access was under prepared

Answer 33

-infected tissue remains in pulp horns; continued reinfection of canal. tooth darkens as pulp breakdown products seep into dentine -Stressed access for instruments, uncontrolled instrumentation, ledging/blockage, instrument damage or # -Missed canal: failure to understand normal anatomy; case doomed to fail

Question 34

errors that can occur during shaping

Answer 34

-apical transportation -ledging -perforation- communication between pulp space and periodontal tissues -stripping -blockage -Zipping - ledging directly at the apical foramen. This can transport the foramen -file fracture -elbow- a narrow part

Question 35

Cause of ledging

Answer 35

-not extending the access sufficiently, incorrect assessment of the canal direction, incorrect WL, forcing a large instrument, using non-curved stainless steel in a curved canal, failure to use instruments in correct order -so avoid these. plenty irrigation. Make sure to use pre-curved SS, or Ni Ti

Question 36

sizes and tapers of shaper 1 and 2 and finisher 1. Their colours

Answer 36

S1 = size 17 tip, progressive 2-11% taper S2 = size 20 tip, progressive 4-11.5% taper F1 = size 20 tip, constant 7% taper (max diameter 1.12mm) eg. taper of 7% means increasing by 0.07mm from tip -Purple, white, yellow

Question 37

what information needs to be recorded in notes at shaping stage

Answer 37

which canal, Reference point, WL, what instruments used to shape and clean, masterfile -MB canal, WL = 21mm to MB cusp tip; 45 MF -ML canal, WL 20mm to ML cusp tip, 40 MF -D canal, WL 21mm to DL cusp tip, 55 MF

Question 38

how to approach a tooth with complex curve

Answer 38

Scout with 10 & 15 files Pre-flare to depth easily reached & irrigate before even thinking of entering apical third

Question 39

requirements for root canal filling material

Answer 39

biocompatible (if over-extended) radiopaque (but not too much) do not support microbial growth capable of compaction (condensation) to fill irregular shapes inert (do not break down with time) controllable (you decide where it goes) capable of removal if required (re-treatment or post space) GP is Commonest bulkroot filling material in combination with sealer. Inexpensive, compressible, can be softened with heat, easy to remove if required. Made of rubber

Question 40

what to do if master GP is too short or too long in canal when taking master GP x-ray.

Answer 40

-too short: irrigate, gently file canal to apex. (10 file and confirm master file) irrigate again and try cone again. If still no good it is probably due to poor size match between files and GP. Try smaller cone and trim tip to tug-back -too long: try another cone or trim tip for better fit. May not have good apical stop so keep going up a size in file

Question 41

the different colours of spreader and how to select the correct size

Answer 41

-must be able to pack the full length of the root filling. should slide in freely. Should fit in 1-2mm minus the WL, using vertical finger pressure -biggest is blue, then green then red (B) -accessory cones must be the size of spreader or smaller

Question 42

what to do if open root apex where length control is difficult

Answer 42

grow a calcific barrier (pack with MTA), or customise GP cones

Question 43

what is MTA. use and properties

Answer 43

-mineral trioxide aggregate -calcium silicate portland type cement the best sealing, most inert, biocompatible material available -for direct pulp caps -for imature apices 4hr setting time gives plenty of handling time But, expensive, difficult to handle, difficult to remove when set (concrete)

Question 44

how to retreat a canal filling if GP extends out of apex

Answer 44

-pull out GP using spiky file there and then, or use solvent to dissolve it away. -Pipette solvent into cavity (orange oil solvent, used to be chloroform) Use size 20 to start scooping out with watch wind technique. Use paper points. Go up to MF and try and engage with the rubber and twist. It takes patience.

Question 45

method and kit used for posts. how much remaining GP you want in the canal

Answer 45

-Use dual tapered light post drills kit: Universal drill. No1, No 2 and No 3 twist drills with fibre posts corresponding to their size -Use gaits glibon bur (size 2 or 3) to drill out GP. You want 4-5 mm remaining GP at the apical 1/3 of apex -Once removed, do quick in and out motion of the universal bur. Make sure GP is cleared from walls. Syringe to wash out debris. Etch to clean chamber -Cut back the other canal slightly so that the composite can flow into it slightly. -Use No.1 twist drill. Move to the next one if there is space and it wiggles about in the canal. You want to use the smallest one possible. -Etch canal. Wash and dry with paper point. Bond. Thin layer of bond onto post and cure. Cement (RelyX) onto post then place into canal. Cure for 40 seconds. -Cut excess post just below the cusp tip so it will be contained within the composite. Fill with composite -cut back for crown prep or onlay

Question 46

difference in preparing a tooth for metal and porcelain onlays

Answer 46

metal - more conservative. knife-edge angle porcelain - more reduction needed as more brittle so needs thicker material. 90 degrees angle to seat onto

Question 47

the process of pulpitis and necrosis

Answer 47

Immune response occurs to fight off infection. Vasodilation (hyperaemia- increased amount of blood) to bring in inflammatory cells. Also get fluid exudate (oedema) from leaky vessels to dilute the irritant. Inflammatory cell exudate includes neutrophils, B & T lymphocytes, plasma cells, immunoglobin, macrophages -Pulp is “boxed in” so you get an increase in pulpal pressure due to oedema which leads to venous stasis. Causes ischaemia (lack of blood flow, cells, oxygen) Also leads to thrombosis (clot formation) which blocks vessels even further, leading to necrosis

Question 48

the progress and severity of inflammation is determined by what factors

Answer 48

nature of irritant, how pathogenic bacteria is, pre-existing state of pulp, apical blood flow, host immune response, anatomy of pulp chamber

Question 49

what is a pulp popyl.

Answer 49

hyperplastic granulation tissue, chronic hyperplastic pulpitis. The pulp polyp is the result of both mechanical irritation and bacterial invasion into the pulp of a tooth that exhibits significant crown destruction due to trauma or caries

Question 50

changes to the pulp during infection

Answer 50

more fibrous, less cells, more dentine deposition, less numerous odontoblasts, oedema, pulpal degeneration, fatty change, calcifications

Question 51

causes of periapical periodontitis

Answer 51

Pulpitis & Pulpal Necrosis Trauma: High restoration, Direct blow to the tooth, Biting, Orthodontics Endodontic treatment: Instrumentation, Chemicals, Root filling materials

Question 52

cellular features of a periodontal granuloma (repair and organisation) what is it

Answer 52

Chronic inflammation, Granulation tissue , Fibrosis Cholesterol clefts, Foreign body giant cells, Foamy macrophages Hyperplastic epithelium -A lesion or growth that develops around tooth apex -consists of a proliferating mass of granulation tissue (new tissue that forms on a wound) and bacteria that forms in response to dead tissue in the pulp chamber of the tooth.  typically starts out as an epithelial lined cyst, and undergoes an inward curvature that results in inflammation of granulation tissue at the root tips of a dead tooth. Treatment includes non-surgical root canal treatment, periapical surgery, or tooth extraction.

Question 53

what is focal scelrosing osteitis/ condensing osteitis. cellular features

Answer 53

Results from inflammation and infection radiopaque mass of sclerotic bone associated with root apex. perhaps some root resorption associated with it, usually microscopical Increased no. and thickness of trabeculae Fibrosed marrow Scattered lymphocytes and plasma cells

Question 54

types of bacteria associated with dentoalveolar abscess

Answer 54

anaerobes - streptococci , gram-positive rods, gram-negative rods microaerophilic streptococci Streptococcus milleri group Peptostreptococcus species Actinomyces species Eubacterium species Porphyromonas species Prevotella species Bacteroides species Campylobacter species Fusobacterium species

Question 55

what is an acute dentoalveolar abscess and cause

Answer 55

localized collection of pus (neutrophils and dead bacteria) in the alveolar bone at the root apex of the tooth. It usually occurs secondary to dental caries, trauma, deep fillings or failed root canal treatment. -swelling intra and sometimes extra oral -no draining sinus

Question 56

what is cellulitis. symptoms. How it differs to oedema

Answer 56

-an infection caused by bacteria getting into the deeper layers of your skin. main symptom of cellulitis is a painful, hot, swollen area of skin. It usually looks red, but this may be less obvious on brown or black skin. -likely systemic signs -oedema= not painful or hot, compressible

Question 57

what is Ludwig's angina. bacteria associated with it

Answer 57

 a bacterial infection (cellulitis) that affects your neck and the floor of your mouth, in the submandibular and sublingual spaces - Caused by tooth infection. Caused by Streptococcus viridans, Staphylococcus epidermis, and Staphylococcus aureus

Question 58

Things to consider at pre treatment assessment for prognosis of a RCT tooth.

Answer 58

limited supra gingival tissue. <3mm supraginigval tissue makes a tooth severely compromised and likely to fail with a root canal bone levels is isolation possible in-tact PDL space no fracture

Question 59

why restoration design is important

Answer 59

Preserve as much tooth structure as possible To minimise damaging internal stresses To protect the remaining tissue from fracture Vertical root fractures are the biggest risk for root filled teeth Cuspal protection must be provided to distribute the load and forces to prevent failure

Question 60

foundations for success for a restoration after RCT

Answer 60

-immediate coronal seal with the GP -good seal at margins with tooth tissue -a definitive restoration made as quickly as possible, certainly within 4/12 -parallel axial walls -2-3mm supraginigval natural tissue for ferrule -no invasion of biological width

Question 61

Requirements for a core. and the material options available and their pros and cons

Answer 61

-Ideally: Strong, biocompatible, resistant to bacterial micro-leakage, insoluble, dimensionally stable, conservative where possible (preserving as much natural tooth so can be restorable again in the future) -Amalgam: High strength, provides seal by corrosion, being phased out, can be retained with grooves, pits, pins, and around direct posts, forgiving technique, delayed crown/onlay preparation, posterior teeth only. Doesn’t fully set until 24 hours, so indirect restoration prep would require patient to come back in for another appointment -Composite High strength, good seal, shrinkage, dimensional stability, technique sensitive, immediate crown/onlay preparation, anterior or posterior teeth -GIC/ RMGIC Generally not strong enough for core placement, useful for infilling, patching up restorations

Question 62

The different options for restoring a tooth after RCT

Answer 62

-direct core using amalgam or composite that may not need a crown -core to provide a foundation for an onlay (metal/ composite. ceramic made in lab then cemented in place) -core to provide a foundation for full coverage crown (metal/ composite/ porcelain/ porcelain + metal) -post may be needed too if little supraginigval tooth tissue

Question 63

what is a Nayyar core. what prep is needed

Answer 63

use pulp chamber anatomy for mechanical retention. cut GP back in canal entrances so restoration can anchor in. use gaits gliddon to remove GP, or use heat system. Cold plugger to ensure solid firm surface. clean walls of chamber with etch or ultrasonic -material packed 2-3mm into canal orifice

Question 64

what his ferrule. why its important

Answer 64

Ideally >2mm height of circumferential dentine is required to resist vertical fracture and provides a protective effect. This is called the “ferrule effect” Helps retain the crown improves survival Ideally the coronal tissue should have parallel walls of dentine extending coronally from the shoulder of the preparation. allows enough tooth surface for composite to be built up

Question 65

when a post would be needed. functions

Answer 65

-used for compromised teeth with not a lot of tooth tissue left for ferrule and retention of the core. -it anchors into a canal space, leaving 4-5mm of GP at the apex -post will be 2/3 of the canal length -provide support and retention for the restoration, distributes force to the root -usually for anteriors as posteriors have more tooth tissue. they have more retention on chamber walls and the three canal entrances allows good mechanical retention (2-3mm into canals)

Question 66

what is IRM material. use. what's it made of

Answer 66

ZOE with PMMA temporary material

Question 67

difference between direct and indirect posts. materials

Answer 67

-Direct: pre-formed metallic posts (stainless steel or titanium) or ceramic or quartz fibre posts. Held in by luting cement.Tend to have larger volume of luting cement than indirect so weaker overall structure. Most common is fibre posts, more flexible than metal to flex like dentine -Indirect: custom made to fit the canal shape -used if little supragingival tissue remaining or the core material cannot be reliably retained

Question 68

factors that affect prognosis of posts

Answer 68

-Accuracy and fit: Poor fitting affects physical properties of the cement, causing possible breakdown, cracking, dissolution of the cement which leads to loosening and loss of restoration, leakage, caries, endo failure. Cements work best in thin section -Length: longer posts retain better. Make as long as possible without compromising root-filing or root. Always leave 4-5mm of root filling material to provide adequate apical seal. Always preserve as much coronal tissyes as possible to maximise post length. -Shape: parallel posts more retentive than tapered, but practiucally there is not much difference so use whatever does least damage. - surface: threaded and serrated more retentive than smooth, but threaded create internal stress -width: wider have better retention, but never want to remove more dentine than required -no rotation -quality of RCT

Question 69

cementing materials for metal posts and fibre posts

Answer 69

metal =zinc phosphate (less retentive) fibre= composite cements (more retentive) Glass-ionomer or resin-modified GIC (good if need more retention)

Question 70

what indirect pulp capping involves. material used

Answer 70

-protects a tooth that has no pulp exposure, and pulp is vital -a thin layer of dentin is left in place to reduce pulp exposure risk . selective caries removal where only infected is removed and affected is left to remineralise -protective dressing is placed on top on remaining dentine - calcium silicate cement (eg. biodentine), GIC, Or setting calcium hydroxide (antimicrobial) Then restored. Reactionary dentine will be produced

Question 71

what is direct pulp capping. when it is done. material used

Answer 71

-treatment of an exposed vital pulp. - when bleeding is controlled -Pulp is covered with a protective dressing or cement placed directly over the pulp at the site of exposure (setting calcium hydroxide or biodentine). -Aims to form reparative dentin and maintenance of vital pulp -not used if pulp is non-vital, irreversible pulpits, PA pathology, large exposure, bleeding not controlled, contamination with saliva (so need rubber dam ASAP)

Question 72

what pulp amputations are available for vital pulp therapies

Answer 72

-Pulpotomy: Excising affected pulp tissue. Cut back to healthy pulp (judge by bleeding using hypochlorite on pledget for 5 mins) Place Calcium silicate cement then restore immediately. -Partial – 1-2mm of superficial pulp -Full – clear full pulp chamber

Question 73

What is selective caries excavation

Answer 73

-selective caries excavation: don't need to remove all affected tissue as it has the ability to remineralise. don't want to risk exposing pulp so leaving a dentine barrier. make sure to clear peripheries. do this in 1 appointment. Done where there is no pulp exposure and pulp is healthy or reversibly inflamed -unlike serial excavation which involves removing infected and affected

Question 74

what is stepwise excavation, traditional and modified technique

Answer 74

-remove most caries then dress the tooth with calcium silicate. Re-enter in 6 weeks where tertiary dentine will form and the caries will remineralise. Second excavation and restore -modified: remove superficial soft caries and clear peripheries. used for deep caries that reach the pulp but no clinical symptoms of irreversible pulptitis. Help reduce pulp exposure risk

Question 75

what material is used for for direct/ indirect pulp capping and why it is good. why calcium hydroxide is not used

Answer 75

-calcium silicate = Sealing the wound so no microorganisms get in. Stimulating stem cells in the cell rich layer which migrate and become odontoblasts (primary odontoblasts are lost in this case as pulp has been exposed. Less soluble, good bonding, high compressive strength -calcium hydroxide= very soluble so if placed under restoration as a pulp cap it will disappear over time and create a gap, micro leakage. It doesn't;t bond very well to dentine so doesn't provide a good dentine barrier

Question 76

what to do if expose the pulp during caries removal

Answer 76

-achieve haemostasis by placing sodium hypochlorite on top with cotton wool pledget -setting calcium hydroxide then GIC to restore -consider pulp capping or pulpotomy as alternatives to pulpectomy and RCT

Question 77

what is pulp revitalisation. what sort of teeth can do this on

Answer 77

-for short roots, significant AP and thin root walls -immature pulps may re-vascularise after schema, provided it has a wide apex >1.1mm and no infection

Question 78

What is the Hall technique

Answer 78

Hall technique where no excavation, just seal in the caries with a PFMC crown to cut off the nutrient supply so that the caries can arrest -put in separators before hand to widen inteproximal gap

Question 79

when would an indirect cap, direct pulp cap, pulpotomy, and pulpectomy be done

Answer 79

-indirect= no pulp exposure, but deep cavity -direct pulp cap = pulp exposure with bleeding controlled <5 mins. Pulp is vital. Exposure size <2.5mm -pulpotomy= pulp exposure where bleeding is uncontrollable. then when more pulp tissue is cut bleeding is controlled within <5 mins as healthy tissue is reached -pulpectomy = bleeding is uncontrollable no matter how much tissue is cut. healthy tissue is never reached

Question 80

Processes of different types of non-vital bleaching

Answer 80

1. Walking bleaching technique: remove GP 2-3mm below epithelial attachment. GIC to seal. Carbamide peroxide on cotton wool sealed in cavity with temporary restoration. Repeated every 2-3 days until desired colour 2. Inside-outside: same as above but access cavity left open and dentist bleaches inside then outside 3. Trays: tray only has space for bleach for the one tooth