Root and Pulp Morphology

Question 1

type I root canal (pulp canal)

Answer 1

one canal to one foramina

Question 2

type II root canal

Answer 2

two separate canals join at one apical foramina

Question 3

type III root canal

Answer 3

two separate canals from chamber continue to two separate apical foramina

Question 4

type IV root canal

Answer 4

one canal from chamber but splits to two canals and two apical foramina

Question 5

incisors often have ___ pulp horns correlating with the ___ facial lobes and ___ mamelons

Answer 5

three (mesial, central, and distal)

Question 6

peg lateral incisors (forming from ___ lobe) are more likely to have only ___ pulp horn

Answer 6

one; one

Question 7

canines have ___ pulp horn under the ___ cusp

Answer 7

one; one

Question 8

anterior teeth most likely have ___ root with ___ canal

Answer 8

one; one (type I)

Question 9

if two canals exist in anterior teeth, most likely one is ___ and one is ____

Answer 9

facial; lingual

Question 10

___ of mandibular incisors are type II or III and under ___ of mandibular canines are type IV

Answer 10

40% ; 20%

Question 11

____ is the only anterior tooth that may have two roots

Answer 11

mandibular canine

Question 12

why pulp cavities get smaller in older teeth

Answer 12

• deposit of secondary (additional) dentin as we age
• new dentin (reparative) forms as a reaction to injury
• calcium hydroxide liner can be used to stimulate additional dentin

Question 13

normally there is ___ pulp horn per functional cusp ; therefore, maxillary premolars have ___ pulp horns

Answer 13

one; two

Question 14

_____ with small lingual cusp may have only one pulp horn (as in canines)

Answer 14

mandibular 1st premolars

Question 15

_____ with 3 cusps have 3 pulp horns

Answer 15

mandibular 2nd premolars

Question 16

all mandibular premolars most often have ___ root with ___ canal

Answer 16

one; one

Question 17

_____ most often have two roots with one canal in each root (57%); even with one root (39%), these teeth most likely have two canals (one buccal and one lingual)

Answer 17

maxillary first premolars

Question 18

____ most often have one root and one canal (but may have two canals)

Answer 18

maxillary 2nd premolars

Question 19

normally molars have ___ pulp horn per functional cusp

Answer 19

one

Question 20

maxillary molars have ___ pulp horns (if ___ cusps are present)

Answer 20

four; four

Question 21

mandibular first molar have ___ pulp horns and mandibular 2nd molar has ___ pulp horns

Answer 21

5; 4

Question 22

maxillary molars most often have 3 roots and ___ canals (two in ____ root), and ___ orifices in the chamber floor

Answer 22

4; mesiobuccal; 4

Question 23

mandibular molars most often have 2 roots but ___ canals (two in the ___ root) and ___ orifices in the chamber floor

Answer 23

3; mesial; four

Question 24

clinical application of pulp morphology related to restorative dentistry

Answer 24

• know shape to avoid exposing pulp when preparing teeth for restorations
• avoid damage to pulp with burs (overheat, dry out)
• determine need for dental bases to protect, insulate, etc.
• knowledge of morphology critical when removing pulp (endodontic therapy)

Question 25

___ of maxillary 1st premolars have 3 roots

Answer 25

4% (2 buccal roots and 1 lingual root with 3 canals)

Question 26

pulp inflamed and cannot be healed

Answer 26

irreversible pulpitis

Question 27

pulp death

Answer 27

necrosis

Question 28

dark area on x-ray around apex of root indicating bone less

Answer 28

periapical radiolucency

Question 29

inflammatory tissue enclosed within a fibrous capsule

Answer 29

granuloma

Question 30

has liquid content

Answer 30

cyst

Question 31

steps to endodontic therapy

Answer 31

• develop access opening (through roof of pulp chamber)
• locate canal orifices (on floor of chamber)
• clean out each canal (remove pulpal tissue)
• fill cleaned canals (with gutta percha)

Question 32

maxillary central incisors: cervical root and chamber outline is ____; cingulum to the ____; no root depressions, but ___ is flatter; ___ root canal

Answer 32

triangular; distal; mesial; one

Question 33

maxillary first premolars: most have 2 roots and 2 canals; root depressions on mesial and distal, but ___ is deeper; ____ at cervical; bifurcation located in ____ half of root; 90% have 2 canals

Answer 33

mesial; mesial crown cavitation; apical

Question 34

cervical outline is ovoid and wide faciolingually with root depression on mesial and distal, but distal deeper; one root canal

Answer 34

maxillary canines

Question 35

cervical outline is ovoid and much wider FL than MD; “bow-like” shape

Answer 35

central and lateral mandibular incisors

Question 36

cervical root and chamber outline is egg shaped

Answer 36

maxillary lateral incisors

Question 37

mandibular 1st and 2nd molars: have 2 roots (mesial and distal); ____ root is wider faciolingually; have ___ canals; ___ root has mesial and distal root depressions; furcation access is located ____ and ____

Answer 37

mesial root wider FL
3 canal (2 in mesial root)
mesial root has M and D root depressions
access located midfacial and midlingual

Question 38

root trunk shorter and roots more spread on ____ than ___ and ____

Answer 38

first molars; seconds; thirds

Question 39

maxillary 1st and 2nd molars have ___ canals (2 in the ____ root); lingual root has slight ____ depression on maxillary 1st molar

Answer 39

4; mesiobuccal; lingual

Question 40

furcation access in maxillary 1st and 2nd molars is located ____, ___, and ____

Answer 40

midfacial; mesial; distal