endodontic lab book

Question 1

Which teeth are commonly difficult for locating canals?

Answer 1

Upper first molars,
lower incisors,
lower canines,
lower first premolars,
lower first molars,
C-shaped molars.

Question 2

What is the average length and canal anatomy of upper first molars?

Answer 2

22mm; 3 roots, 4 canals (MB2 sometimes joins MB1).

Question 3

What is the average length and canal anatomy of lower incisors?

Answer 3

22mm; 1 root, 2 canals (40% of cases).

Question 4

What is the average length and canal anatomy of lower canines?

Answer 4

27.5mm 1/2 canals

Question 5

What is the average length and canal anatomy of lower first premolars?

Answer 5

23mm; 1 root, 2 canals (24%).

Question 6

What is the average length and canal anatomy of lower first molars?

Answer 6

22mm; usually 2 roots, sometimes 3.

Question 7

Describe the orifice in C-shaped molars.

Answer 7

Single ribbon-shaped orifice, arching from mesiolingual line angle to distal aspect of pulp chamber.

Question 8

What is the law of symmetry in root canal anatomy?

Answer 8

Except for maxillary molars, canal orifices are equidistant from a line drawn mesio-distally through the pulp floor.

Question 9

What is the color of the pulp chamber floor compared to the walls?

Answer 9

The floor is always darker.

Question 10

Where are root canal orifices located?

Answer 10

At the junction of walls and floor, and at the terminus of root developmental lines.

Question 11

What are signs of dentine hypersensitivity?

Answer 11

Sharp pain to cold/air; no radiographic changes; managed with OHI and fluoride.

Question 12

What are signs of reversible pulpitis?

Answer 12

Sharp, short pain to hot/cold; exaggerated cold response; managed with temporary restoration and desensitisers.

Question 13

What are signs of irreversible pulpitis?

Answer 13

Throbbing pain, lasts minutes-hours, poorly localized; managed with extirpation, RCT, or extraction.

Question 14

What are signs of pulpal necrosis?

Answer 14

No symptoms, discolouration, negative sensibility tests; managed with RCT or extraction.

Question 15

What is acute apical periodontitis?

Answer 15

Tenderness to bite; -ve sensitivity test; PDL widening; manage occlusion, access & dress.

Question 16

What is chronic apical periodontitis?

Answer 16

Asymptomatic or mild ache, periapical radiolucency, -ve sensitivity test; managed by monitoring or RCT/extraction.

Question 17

What is chronic apical periodontitis with acute exacerbation?

Answer 17

Dull, throbbing pain, percussion tenderness, radiolucency; access and calcium hydroxide dressing.

Question 18

What are features of a periapical abscess?

Answer 18

Swelling, throbbing pain, -ve sensitivity, radiolucency; manage with access, drainage, and RCT or extraction.

Question 19

What are the stages of endodontic treatment?

Answer 19

LA → Isolation → Access → Shaping & Cleaning → Obturation → Restoration.

Question 20

Why is isolation important in endodontics?

Answer 20

Prevents contamination, protects airway and tissues, and ensures aseptic conditions.

Question 21

hat is the overriding principle of Schilder’s shaping?

Answer 21

Create a shape we can irrigate and obturate.

Question 22

What is the basic protocol for Protaper Gold instrumentation?

Answer 22

Coronal flare (SX, S1, S2) → WL with S1/S2 → F1 and F2 to WL → Irrigate and patency file between.

Question 23

How is working length (WL) determined?

Answer 23

File to apex, watch for 0 reading on EAL, subtract 0.5mm from that.

Question 24

When is irrigation most effective?

Answer 24

After canal shaping is complete.

Question 25

Why use side-vented needles?

Answer 25

To prevent extrusion and injury.

Question 26

How do we prevent sodium hypochlorite accidents?

Answer 26

Use rubber dam, measure files/syringes, avoid wedging needle, keep needle in motion.

Question 27

What are signs of a sodium hypochlorite accident?

Answer 27

Pain, bleeding, swelling.

Question 28

What is the immediate management?

Answer 28

Irrigate with saline, place calcium hydroxide, pain control with LA and analgesics.

Question 29

How do you manage swelling or sequelae?

Answer 29

NSAIDs, steroids, antibiotics if needed; monitor and consider referral.

Question 30

Why is a temporary restoration important?

Answer 30

Maintains a sterile environment between visits.

Question 31

What is used for interappointment dressing?

Answer 31

Non-setting calcium hydroxide + cotton pledget + reinforced GIC.

Question 32

When should a canal be obturated?

Answer 32

After disinfection, absence of symptoms, and canal is dry.

Question 33

What are the aims of obturation?

Answer 33

Seal pulp space, prevent reinfection, block nutrient supply.

Question 34

What are properties of an ideal root canal filling material?

Answer 34

Stable, easy to place/remove, biocompatible, radiopaque, antibacterial.

Question 35

What are steps of cold lateral condensation?

Answer 35

Master cone fitting (tug back), dry canal, sealer, spreader + accessory cones, radiograph, coronal GP removal, RMGIC lining.

Question 36

What are common problems during obturation?

Answer 36

Canal not dry, no tug back, GP bends or comes out, sealer sets too fast, root fracture, short fill, overfill, voids.

Question 37

: When should restorability be assessed?

Answer 37

Before starting endodontic treatment.

Question 38

What are the functions of restoring a RFT?

Answer 38

Prevent reinfection, protect tooth, restore function/aesthetics, maintain periodontal health.

Question 39

What are the key symptoms of a sodium hypochlorite accident?

Answer 39

Sudden onset of acute pain, bleeding/haemorrhage from the root canal, and swelling within minutes to hours.

Question 40

What is the immediate management of a sodium hypochlorite accident?

Answer 40

Irrigate the canal with saline, apply calcium hydroxide, place a temporary filling, ensure occlusion is not proud, and manage pain with analgesics.

Question 41

What pain relief is recommended following a sodium hypochlorite accident?

Answer 41

: Paracetamol 1000mg up to 4x/day and Ibuprofen 400-600mg up to 4x/day

Question 42

How is swelling managed following a sodium hypochlorite accident?

Answer 42

NSAIDs, consider steroids if swelling is rapid, and antibiotics if there’s pre-op swelling or tissue necrosis.

Question 43

What follow-up protocol is recommended after a sodium hypochlorite accident?

Answer 43

Phone call same day, daily calls for a few days, then 1-2 times weekly; severe cases need longer follow-up and possible referral.

Question 44

How can sodium hypochlorite accidents be prevented?

Answer 44

Use rubber dam, measure correct working length, safe-ended needles, passive syringe movement, use index finger not thumb, avoid locking syringe into canal, and use low concentration hypochlorite (0.5–5.25%).

Question 45

When should the restorability of a root-filled tooth be assessed?

Answer 45

Before beginning endodontic treatment.

Question 46

What are key factors in coronal tissue assessment?

Answer 46

Quantity (min. 1.5–2mm ferrule), thickness, and position of remaining tooth structure.

Question 47

What occlusal considerations are important when restoring post-crowned teeth?

Answer 47

Posterior: only ICP contact. Anterior: incisal guidance shared across all anterior teeth. Post crowns shouldn’t provide canine guidance.

Question 48

What are important aesthetic factors when restoring an RFT?

Answer 48

Tooth shape, shade, and any discolouration.

Question 49

What is the primary purpose of a post?

Answer 49

To retain the core.

Question 50

: Does post material affect tooth survival?

Answer 50

No, post material has no effect on survival rate.

Question 51

What is the ideal post length?

Answer 51

Longer than the clinical crown with at least 4mm of gutta-percha remaining to preserve apical seal.

Question 52

Should dentine be sacrificed to place a post with modern techniques?

Answer 52

No, adhesive technology avoids unnecessary dentine removal.

Question 53

What types of posts are commonly used?

Answer 53

Tapered and parallel-sided direct posts (e.g. LDI).

Question 54

What key elements should be included in endodontic records?

Answer 54

Provisional/definitive diagnosis, discussed treatment options, prognosis, informed consent (risks), and treatment records.

Question 55

What risks should be communicated during consent for RCT?

Answer 55

Tooth fracture, damage, blocked canals, persistent infection, bleach leakage, and instrument fracture.

Question 56

What happens in the first RCT appointment for a lower molar?

Answer 56

Confirm diagnosis, LA, rubber dam, remove caries/restoration, assess restorability, extirpation, dressing.

Question 57

What occurs during the instrumentation appointment?

Answer 57

Re-access, chemo-mechanical prep, working length determination, irrigation, dressing, and temporisation.

Question 58

What happens during the obturation/restoration appointment?

Answer 58

Master cone fitting, obturation with GP and sealer, post-op radiograph, core restoration (likely composite), use of matrix and wedge.

Question 59

When is a preoperative radiograph taken and why?

Answer 59

Before treatment, to assess full root length and 2–3 mm periapical region.

Question 60

When is a working length radiograph needed?

Answer 60

To determine accurate canal length—often multiple radiographs may be needed.

Question 61

What is the purpose of a master point/master file radiograph?

Answer 61

To verify canal preparation and working length prior to obturation.

Question 62

When is the post-obturation radiograph taken and what should it show?

Answer 62

After obturation—it should show complete fill of canal, intact apical seal, and no voids.

Question 63

Answer 63

A

Question 64

Answer 64

B

Question 65

Answer 65

A

Question 66

Answer 66

C

Question 67

Answer 67

b

Question 68

Answer 68

D

Question 69

Answer 69

A