endodontic anatomy

Question 1

what is the pulp cavity divided into?

Answer 1

pulp chamber and horns, root canals

Question 2

pulp chamber

Answer 2

one per tooth, most occlusal or incisal portion of pulp cavity.

Question 3

pulp chambers of anterior teeth

Answer 3

partly in the crown

Question 4

pulp chambers of posterior teeth

Answer 4

mostly in the cervical part of the root

Question 5

what are the walls of pulp chamber made of?

Answer 5

inner most layer of dentin

Question 6

where is the roof of the pulp chamber?

Answer 6

incisal or occlusal border

Question 7

pulp chamber floor

Answer 7

for teeth with multiple roots, the openings into the roots are called orfices

Question 8

pulp horns

Answer 8

projections at the roof of the pulp chamber; molars, PM’s, canines have 1 per cusp. Young incisors have 3 horns( 1 for each lobe).

Question 9

whats the exception for young incisors with 3 horns?

Answer 9

peg lateral ( maxillary)- only has one pulp horn because it has 1 lobe

Question 10

connecting point of root canal and pulp chamber is what

Answer 10

orfices.

Question 11

what are accessory ( lateral) canals?

Answer 11

when the root canal splits and gives off an additional branch. Usually in apical 1/3 of root, and furcation area of roots.

Question 12

what are the 4 different canals based off of?

Answer 12

shape and number of canals in any one root

Question 13

type 1

Answer 13

one canal , one foramen

Question 14

type 2

Answer 14

2 canals, one foramen

Question 15

type 3

Answer 15

2 separate canals, 2 separate foramina

Question 16

type 4

Answer 16

one canal, 2 foramina

Question 17

pulp chamber and horns of anterior teeth

Answer 17

incisors often have 3 pulp horns ( mesial, central, distal), Peg lateral incisors ( form from 1 lobe) usually have 1 horn, canines have 1 pulp horn under the 1 cusp

Question 18

anterior teeth root canals

Answer 18

most likely 1 root w/ 1 canal; if 2 canals exist there is 1 facial and 1 lingual

Question 19

pulp chamber and horns in premolars

Answer 19

normally 1 pulp horn per functional cusp so most have 2 horns; mandibular 1st PM has 1 horn; mandibular 2nd has 3 horns.

Question 20

root canals and orfices in PM’s

Answer 20

all except maxillary 1st have 1 root w/ 1 canal; maxillary 1st PM’s most often have 2 roots w/2 canals,( even if the roots are fused it stays the same)

Question 21

maxillary 2nd PM’s root canal and orfices

Answer 21

usually 1 root w/1 canal but 2 canals are frequently present; with 1 canal its orfice is in the exact center of the tooth. If the orifice is more buccal or lingual there are probably 2 canals

Question 22

mandibular PM’s root canal and orifices

Answer 22

mostly 1 root w/1 canal, but mandibular 1st may have 1 canal that splits into 2 canals with 2 orifices (type IV)

Question 23

pulp chamber and horns of maxillary molars

Answer 23

chambers of 1st & 2nd molars is broader buccolingually than mesiodistally ( just like crown) and often constricted near floor of chamber; cusp of carabelli is functionless so no horn

Question 24

pulp chamber and horns of mandibular molars

Answer 24

1st & 2nd is broader mesiodistally than buccolingually ( like crown ); mandibular 1st with 5 cusps is the only tooth with 5 pulp horns

Question 25

root canal & orifices of maxillary molars

Answer 25

most often have 3 roots w/4 canals ( 2 in mesiobuccal root), and 4 orifices in the chamber floor

Question 26

root canal & orifices of mandibular molars

Answer 26

most often have 2 roots but 3 canals ( 2 in mesial) and 3 orifices in the chamber floor

Question 27

pulp shape in primary teeth

Answer 27

pulp is very large with thinner enamel and dentin

Question 28

why do pulp cavities get smaller with age?

Answer 28

deposit of secondary dentin as we age, reparative dentin, calcium hydroxide base can be used to stimulate additional dentin

Question 29

endodontics is defined as…..

Answer 29

a specialty concerned with human dental pul and periapical tissues. ( they are the plumbers)

Question 30

pulpal disease

Answer 30

pulp inflamed and irreversible. Appears dark on xray

Question 31

periapical disease

Answer 31

periapical radiolucency is the dark area on x-ray around apex indicating bone loss

Question 32

pulp death

Answer 32

necrosis, tooth dies but tooth still functions

Question 33

crown discoloration is a result of what?

Answer 33

pulpal disease that was caused be trauma many years prior.

Question 34

steps to endodontic therapy

Answer 34

develop access opening, locate canal orifices, clean out each canal, fill cleaned canals with gutta percha

Question 35

endodonotic therapy may require

Answer 35

a restoration with a post and core, and crown

Question 36

important anatomy for maxillary centrals incisors

Answer 36

cervical root and chamber outline is triangular, cingulum is distal, no prominent root depressions, one root canal

Question 37

important anatomy for mandibular central and lateral incisors

Answer 37

cervical outline is ovoid ( wider faciolingually than mesiodistally), root depression on mesial and distal; distal is deeper, one canal most often

Question 38

important anatomy for maxillary canines

Answer 38

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

Question 39

important anatomy for mandibular canines

Answer 39

cervical outline is wider faciolingually, root depression on mesial and distal, distal is deeper, one canal most often, may have 2 roots and 2 canals

Question 40

important anatomy for maxillary 1st PM’s

Answer 40

most have 2 roots and 2 canals, root depression mesial and distal with mesial deeper, mesial crown cavitation at cervical, furcation located in apical half

Question 41

important anatomy for maxillary 2nd PM’s

Answer 41

cervical outline at cervical is ovoid ( wider buccolingually), normally one root and one canal, root depression on mesial and distal with distal deeper,

Question 42

important anatomy for mandibular 1st PM’s

Answer 42

cervical outline is ovoid ( wider buccolingually) root depressions mesial and distal deeper on distal, one canal most often

Question 43

important anatomy for mandibular 2 PM’s

Answer 43

cervical outline is ovoid, wider buccolingually than mesiodistally, root depression not common on mesial frequent on distal, one canal most often, crown outline of three-cusp type wider in lingual half

Question 44

mandibular first and second molars

Answer 44

2 roots ( mesial, distal) , mesial root is wider facriolinugally, 3 canals ( 2 in mesial root), mesial root with mesial and distal root depressions, furcation access is located midfacial and midlingual, root trunk shorter and roots more spread on first molars than second and third.

Question 45

maxillary first and second molars

Answer 45

3 roots ( mesiobuccal, distobuccal, and lingual), 4 canals ( 2 in mesiobuccal), mesiobuccal root is wider than distobuccal, mesiobuccal root has mesial and distal depression, lingual root has slight lingual depression

Question 46

maxillary first and second molars contd

Answer 46

furcation access is located midfacial, mesial, and distal, maxillary first molar often has distal cervical depression, first molars have shorter root trunk and more spread roots than seconds and thirds.