Pulpal Anatomy and Root Morphology

Question 1

what does the periodontium include

Answer 1

gingiva, cementum, periodontal ligament, alveolar bone

Question 2

what is the free gingiva

Answer 2

most incisal unattached portion, surrounds tooth to form a collar of tissue with a space or sulcus

Question 3

what does the free gingival groove separate

Answer 3

attached gingiva from free gingiva

Question 4

what is the attached gingiva

Answer 4

zone of gray to light or coral pink keratinized masticatory mucosa that is firmly bound to underlying

Question 5

what does the attached gingiva extend between

Answer 5

free gingiva and alveolar mucosa

Question 6

what is the mucogingival junction between

Answer 6

attached gingiva and the looser, alveolar mucosa

Question 7

where is the alveolar mucosa

Answer 7

tissue apical to the mucogingival junction

Question 8

where is the gingival sulcus

Answer 8

space between tooth surface and narrow cervical collar of free gingiva

Question 9

what are the functions of the pulp and what does each do

Answer 9

-formative: pulp cells form dentin (primary function)
-nutritive: blood supply to tooth
-sensory: nerve supply to tooth
-defensive: forms reparative dentin in response to mechanical, thermal, chemical, and bacterial insults

Question 10

how many pulp horns does the maxillary central incisor have

Answer 10

3

Question 11

describe the incisal view of the maxillary central incisor

Answer 11

triangular, mesial wall is longer than the distal

Question 12

describe the root of the maxillary lateral incisory

Answer 12

root is pointed
-as long or longer than central incisor
2 pulp horns

Question 13

describe the root and pulp of the maxillary canine

Answer 13

-broadest single rooted tooth FL
- distal>mesial developmental depressions
-anterior tooth least likely to have bifurcated root
-1 pulp horn

Question 14

describe the root and pulp of the mandibular central incisor

Answer 14

-broader FL than MD
-distal> mesial developmental depressions
-root is round/oval
- one pulp canal, 2 40% of the time

Question 15

describe the root and pulp of the mandibular lateral incisor

Answer 15

-distal>mesial developmental depression
-depressions are more pronounced than central incisor
- usually one pulp canal, 2 40% of the time

Question 16

describe the root and pulp of the mandibular canine

Answer 16

-often curved to mesial
- anterior tooth most likely to have a bifurcated root
-wide FL
-deep distal developmental depression, no mesial

Question 17

what are indicators of gingivitis

Answer 17

redness, rolled margins, smooth and shiny surface texture, loss of resiliency, bleeding upon probing

Question 18

what are symptoms of periodontitis

Answer 18

loss of attachment and underlying bone with increased pocket depths

Question 19

what is gingival recession

Answer 19

apical migrations of gingival tissue, with underlying bone loss, resulting in exposure of root surface

Question 20

what are contributing factors to gingival recession

Answer 20

poorly aligned teeth, lack of attached gingiva, aggressive tooth brushing

Question 21

what is furcation involvement

Answer 21

with advanced perio disease, attachment loss and bone loss may reach a furcation area

Question 22

describe the roots of maxillary first premolars

Answer 22

-two roots 50-60% of the time
-90% of time has 2 canals
-broad FL
-long root trunk (1/2-2/3 length of root)
-cross section: kidney bean shaped
-pronounced cavity on mesial

Question 23

describe the pulp of the maxillary first premolars

Answer 23

-broad BL
-2 canals in the apical 1/3
-2 pulp horns

Question 24

where does the pulp chamber become the root canal

Answer 24

at a level below the CEJ

Question 25

describe the root and pulp of the maxillary second premolars

Answer 25

-single root
- 50% have 2 canals
- broad FL
-2 pulp horns
-cross section: oval or kidney shaped

Question 26

describe the roots of the maxillary first molar

Answer 26

-3 roots
-MB root is broad FL and has 2 canals in 90-95% of cases
-most splayed roots of any tooth in the mouth

Question 27

describe the pulp chamber of the maxillary first molar

Answer 27

-large pulp chamber with 4-5 horns
-MB pulp horn is most at risk of exposure during procedures
- cross section: MB line angle is acute, DB obtuse, lingual right angles
-palatal canal centered lingually

Question 28

what are the canals in the MB root of the maxillary first molar

Answer 28

MB canal and the accessory MB canal. accessory is lingual to MB canal

Question 29

describe the roots of the maxillary second molar

Answer 29

-roots are straighter, closer together and more distally inclined
-roots may fuse together

Question 30

describe the pulp chamber of the maxillary second molar

Answer 30

-cross section:MB and DB line angles are more acute and more obtuse than first molar
-pulp chamber is more triangular in shape
-MB usually has one canal (two canals only 30% of the time)

Question 31

describe the root and pulp of the mandibular first premolar

Answer 31

-one canal and 2 pulp horns
-premolar most likely to have 1 pulp horn
-buccal pulp horn is at risk during cavity preparations
-broader FL

Question 32

describe the root and pulp of the mandibular second premolar

Answer 32

-pulp horns are more prominent and usually 3 present-1 buccal and 2 lingual

Question 33

describe the root and pulp of the mandibular first molar

Answer 33

-2 roots
-mesial root: broad FL, 2 canals in 60% of cases, 40% have type 2 canals , curves distally
- distal root: broad and may contain ribbon shaped canal, 1-2 canals in the distal root

Question 34

describe the roots and pulp of the mandibular second premolar

Answer 34

-mesial root: 2 separate canals in 35% of cases, 65% have type 2
-more variation in second molar canal anatomy

Question 35

how far along are the roots developed when tooth first erupts into oral cavity

Answer 35

50%

Question 36

in a molar where do the pulp canals usually join the chamber

Answer 36

at a level apical to the CEJ