Endodontics

Question 1

what are the three design objectives of RCT

Answer 1

create continuously tapering funnel
maintain apical foramen
keep apical opening as small as possible

Question 2

what material are K files made from and why

Answer 2

stainless steel or nickel titanium
cross sectional shape allows greater flexibility

Question 3

how is the watch winding motion for RCT used

Answer 3

backwards ossilation of 30
forwards ossilation of 60
light apical pressure

Question 4

when is the watch winding technique for RCT useful

Answer 4

for passing small files through canals

Question 5

what is the balanced force motion in RCT preparation

Answer 5

1/4 turn clockwise
1/2 turn anticlockwise
repeat 1-3 times, remove, clean and reintroduce

Question 6

name an advantage of using reciprocation system for RCT

Answer 6

mimics manual movement
reduces risk associated with continuously rotating a file through canal curvatures

Question 7

name two disadvantages of reciprocation system for RCT

Answer 7

decreased cutting efficiency
requires increased inward pressure
limited capacity to get debris out the canal

Question 8

what is cyclic fatigue

Answer 8

it is the stress/ strain and deformation induced in a material from cyclic loading

Question 9

what does the regressive taper on reciproc instreuments allow for

Answer 9

coronal shaping without unnecessary loss of tooth substance

Question 10

what are the rotations of reicprocation instruments

Answer 10

150 anticlockwise then
30 clockwise

Question 11

why should the three peck movement be used with reciproc instruments

Answer 11

the flutes will become blocked if not cleaned after 3 pecks and this would increase friction in the instrument which causes the instrument to not work as well in the canal

Question 12

what size of hand instrument is used to determine working length

Answer 12

ISO size 10

Question 13

what is reciproc blue

Answer 13

there is heat treatment on the traditional NiTi alloy
has higher flexibility
suitable for strongly curved canals

Question 14

how many canals does a maxillary central incisor have

Answer 14

1

Question 15

how many canals does a maxillary lateral incisor have

Answer 15

1 (distal curve)

Question 16

how many canals does a maxillary canine have

Answer 16

1 (distal curve)

Question 17

how many canals does a maxillary 1st premolar have

Answer 17

2-3

Question 18

how many canals does a maxillary 2nd premolar have

Answer 18

1-3

Question 19

how many canals does a maxillary 1st molar have

Answer 19

3

Question 20

how many canals does a maxillary 2nd molar have

Answer 20

3

Question 21

how many canals does a mandibular central incisor have

Answer 21

1

Question 22

how many canals does a mandibular lateral incisor have

Answer 22

1

Question 23

how many canals does a mandibular canine have

Answer 23

1

Question 24

how many canals does a mandibular 1srt premolar have

Answer 24

1

Question 25

how many canals does a mandibular 2nd premolar have

Answer 25

1

Question 26

how many canals does a mandibular 1st molar have

Answer 26

2-3

Question 27

how many canals does a mandibular 2nd molar have

Answer 27

2

Question 28

name five reasons why biofilms cause resistance

Answer 28

antimicrobials fail to penetrate antimicrobials get trapped/ destroyed antimicrobials not active against non-growing microorganisms expression of resistance genes stress response to hostile environment

Question 29

name 2 clinical objectives of RCT

Answer 29

removing canal contents eliminating infections

Question 30

what is reactionary dentine

Answer 30

tubular and irregular structure formed by original odontoblasts

Question 31

what is reparative dentine

Answer 31

atubular and characterised by dead tracts where odontoblastic layer has been eradicated formed by odontoblast like cells

Question 32

where is the dental-pulp complex derived from embryologically

Answer 32

neural crest derived ectomesenchyme

Question 33

what is enamel derived from embryologically

Answer 33

ectoderm

Question 34

what endodontic diseases can periapical radiolucency be associated with

Answer 34

reversible pulpitis, irreversible pulpitis and pulpal necrosis

Question 35

what occurs in response to bacterial ingress in the pulp chamber

Answer 35

acute inflammation vasodilation and increased pulpal blood flow extravasation due to increased vascular permeability

Question 36

describe the pulp

Answer 36

unmineralised tissue composed of soft connective tissue, vascular, lymphatic and nervous elements encased in hard tissue

Question 37

what is (peri)apical periodontitis

Answer 37

acute or chronic inflammatory lesions around the apex of the tooth root caused by bacterial invasion of the pulp

Question 38

what occurs when there is an inflamed ligament around the tooth

Answer 38

apical periodontitis - which progresses to bone loss round the apex of the tooth

Question 39

what is an acute abscess

Answer 39

occurs quickly accumulation of pus

Question 40

what is a chronic abscess

Answer 40

occurs slowly can lead to sinus formation

Question 41

what warning signs should you look for when monitoring an abscess so it doesn't turn into cellulitis

Answer 41

malaise fever cellulitis lymphadenopathy persistent swelling

Question 42

what is a dental abscess

Answer 42

localised collection of pus that forms inside the teeth or gyms which essentially initiates from bacterial infection

Question 43

what is a radicular cyst

Answer 43

arises from cell rests of mallassez, in the periodontal ligament in response to inflammation after pulp death

Question 44

name three potential complications of endodontic infection

Answer 44

maxillary sinusitis ludwig's angina cavernous sinus thrombosis

Question 45

which tooth fibres supply a sharp pricking sensation/ early shooting pain when activated

Answer 45

a-delta fibres

Question 46

which tooth fibres supply a dull aching or burning pain when activated

Answer 46

c fibres

Question 47

what is referred pain usually provoked by

Answer 47

intense stimulation of C-fibres leading to intense slow, dull pain

Question 48

where does referred pain always radiate to

Answer 48

same side

Question 49

what should you examine clinically as part of an endodontic exam

Answer 49

extra and intra oral soft tissue exam intra oral swellings sinus tracts palpation percussion mobility periodontal exam

Question 50

why are heat tests not always recommended for sensibility testing

Answer 50

they can cause irreversible pulpitis

Question 51

what tooth fibres are stimulated when using the EPT

Answer 51

A-delta fast conducting fibres

Question 52

when is the EPT considered unreliable

Answer 52

in teeth with open apices

Question 53

what are the 5 AAE pulpal diagnoses

Answer 53

normal pulp reversible pulpitis symptomatic irreversible pulpitis asymptomatic irreversible pulpitis pulpal necrosis

Question 54

name the 6 AAE apical diagnoses

Answer 54

normal apical tissues symptomatic apical periodontitis asymptomatic apical periodontitis chronic apical abscess acute apical abscess condensing osteitis

Question 55

what is symptomatic apical periodontitis

Answer 55

inflammation of the apical periodontium ' painful response to biting severe pain on percussion and indicative of degenerating pulp

Question 56

what is asymptomatic apical periodontitis

Answer 56

inflammation and destruction of the apical periodontium that is of pulpal origin appears as apical radiolucency no clinical symptoms

Question 57

what is a chronic apical abscess

Answer 57

inflammatory reaction to pulpal infection gradual onset little/ no discomfort discharge of pus through sinus tract

Question 58

what is an acute apical abscess

Answer 58

inflammatory reaction to pulpal infection rapid onset spontaneous pain/ extreme TTP/ pus formation

Question 59

what is condensing osteitis

Answer 59

abnormal bone growth (radiopaque lesion) resulting from inflammation or infection usually seen at apex of the tooth

Question 60

when is pregnancy maybe a contraindication to endo treatment

Answer 60

in first trimester only emergency intervention

Question 61

what medical conditions are contraindications to endo treatment

Answer 61

myocardial infarction within past 6 months cancer - radiotherapy and chemotherapy to head and neck can compromise healing allergy to latex - GP not a risk as non-cross reactive

Question 62

what restorative factors may deem a tooth to be un-root-treatable

Answer 62

sub-osseous caries poor crown/ root ratio misalignment of teeth presence of pre-existing full coverage restorations

Question 63

what type of mirrors are better for endodontic treatment

Answer 63

front surface mirrors