Oral Anatomy Final - Periodontia and Root/Pulp Morphology

Question 1

What are the three numbering systems of teeth? Describe each.

Answer 1

1. Universal Numbering System - adult teeth numbered 1-32 and primary teeth numbered A-T
2. Palmer Notation - adult teeth given a number 1-8 and the quadrant is designated by corners drawn around numbers; primary teeth are A-E
3. International System - adult teeth given a number 1-8 and quadrant is designated with a number 1-4; primary teeth quadrant given a number 5-8

Question 2

What are the two zones of gingiva?

Answer 2

• free gingiva

- attached gingiva (keratinized)

Question 3

What are the six types of periodontal ligament fibers?

Answer 3

• apical
• oblique
• horizontal
• alveolar crest
• free gingival
• transeptal

Question 4

What are the 4 structures that make up the periodontium?

Answer 4

• gingiva (free and attached)
• periodontal ligament fibers
• alveolar bone
• root cementum

Question 5

What are the functions of healthy gingiva?

Answer 5

• support (attaches the gingiva to the tooth and the cementum)
• esthetics
• protection (protects due to tough tissue layer that is keratinized)
• phonetics (affected by open embrasures that allow air to whistle through spaces)

Question 6

What are the 3 diseases associated with periodontia?

Answer 6

• gingivitis
• periodontitis
• gingival recession

Question 7

What are the associated factors with gingival recession?

Answer 7

• crowding
• prominent roots
• bone recession
• bony dehiscence (isolated area of tooth root denuded of its bony covering)

Question 8

What is an operculum?

Answer 8

a flap of tissue that may remain over part of the chewing surface of the mandibular last molar that is prone to irritation and infection

Question 9

What is the difference between plaque and calculus?

Answer 9

Plaque is a thin layer containing organized microorganisms that loosely adhere to teeth, but can be removed with proper tooth brushing and flossing.
Calculus is a hard complex mineral layer formed from plaque that is firmly attached to the tooth (calcium in the calculus may come from saliva or blood/tissue fluid).

Question 10

What are the 8 indicators of periodontal disease and conditions?

Answer 10

• tooth mobility
• probe depths
• gingival margin level (gingival recession/non-recession)
• clinical attachment loss
• bleeding on probing (BOP)
• furcation involvement
• mucogingival defects
• plaque index

Question 11

What is the typical depth of the gingival sulcus?

Answer 11

1-3mm

Question 12

What is the definition of clinical attachment loss (clinical attachment level)?

Answer 12

the distance from the CEJ to the apical extent (depth) of the periodontal sulcus; measurement indicates how much support has been lost and is a critical determinant of whether periodontal disease has occurred

Question 13

Where is the furcation involvement checked for maxillary molars?

Answer 13

midfacial, mesial, and distal

Question 14

Where is the furcation involvement checked for mandibular molars?

Answer 14

midlingual and midfacial

Question 15

What are the 3 types of mucogingival defects?

Answer 15

• keratinized gingiva is present but is not attached (in other words, gingival suclus is deeper than attached gingiva)
• visual lack of keratinized gingiva (or very narrow keratinized gingiva)
• movement or blanching at the gingival margin when the frenum is moved

Question 16

What is the name of the opening between the pulp chamber to the pulp canal?

Answer 16

orifice

Question 17

What is a Type I root canal? What teeth can this be found in?

Answer 17

one canal to one apical foramina; may be found in most maxillary incisors and canines as well as mandibular premolars

Question 18

What is a Type II root canal?

Answer 18

two separate canals join at one apical foramina

Question 19

What is a Type III root canal? What teeth can this type be found in?

Answer 19

two separate canals from the pulp chamber continue to two separate apical foramina; may be found in maxillary first premolar

Question 20

What is a Type IV root canal? What teeth may this type be found in?

Answer 20

one canal from the pulp chamber but splits into two canals and two apical foramina; may be found in mandibular canines (less than 20%)

Question 21

How many pulp horns are usually found in incisors?

Answer 21

3 pulp horns (one for each facial lobe/mamelon); peg lateral incisors, which form from only one lobe, are more likely to have only one pulp horn

Question 22

How many pulp horns can be found in canines?

Answer 22

one pulp horn under the one cusp

Question 23

Do pulp cavities get bigger or smaller as teeth grow older? Why?

Answer 23

Pulp cavities get smaller as teeth age.
This is because:
-deposit of secondary (additional) dentin as we age
-new dentin (reparative) forms as reaction to injury
-calcium hydroxide liner can be used to stimulate additional dentin

Question 24

How many pulp horns are found in maxillary premolars?

Answer 24

two horns (one per functional cusp)

Question 25

How many pulp horns are found in mandibular premolars?

Answer 25

Mandibular first premolars with a functionless lingual cusp may only have one pulp horn. Mandibular second premolars may have 2-3 pulp horns depending on the number of cusps.

Question 26

How many pulp horns are found in molars?

Answer 26

One pulp horn per functional cusp so: -maxillary first molars and 4-cusp second molars would have 4 horns (cusp of Carabelli does not have a horn) -3-cusp maxillary second molars would have 3 horns -mandibular first molars would have 5 horns mandibular second molars would have 4 horns

Question 27

How many root canals are in maxillary molars?

Answer 27

Maxillary molars have 3 roots and usually 4 canals with 2 canals in the mesiobuccal root and 1 in each of the other two roots

Question 28

How many root canals are in mandibular molars?

Answer 28

Mandibular molars often have 2 roots but 3 canals with 2 canals in the mesial root and 1 canal in the distal root.

Question 29

How does the pulp shape in primary teeth compare to that of secondary teeth?

Answer 29

Primary teeth have a pulp that is proportionally larger than on secondary teeth. Dentin and enamel is thinner so the pulp is closer to the external surface.

Question 30

What is the definition of endodontics?

Answer 30

a specialty concerned with morphology, physiology, and pathology of human dental pulp and periapical tissues

Question 31

What are the 3 pulpal and periapical diseases?

Answer 31

- irreversible pulpitis - pulp is inflammed and cannot heal - periapical disease - 3 types (periapical radiolucency, granuloma, cyst) - pulp death (necrosis)

Question 32

What is periapical radiolucency?

Answer 32

dark area on x-ray around apex indicating bone loss

Question 33

What is a granuloma?

Answer 33

inflammatory tissue enclosed within a fibrous capsule

Question 34

What is indirect pulp capping?

Answer 34

the decay close to the pulp is left during restoration and secondary dentin is formed and after awhile, decay can be removed without damaging the pulp

Question 35

What is direct pulp capping?

Answer 35

expose the pulp to medicament to stimulate secondary dentin formation

Question 36

What are the steps of endodontic therapy?

Answer 36

1. develop access opening through roof of the pulp chamber 2. locate canal orifices on the floor of the chamber 3. clean out each canal by removing pulp tissue 4. filled cleaned canals with gutta percha

Question 37

What tooth is described below? - cervical root and chamber outline is triangular - cingulum to the distal - no root depressions (mesial is flatter) - one root canal

Answer 37

maxillary central incisor

Question 38

What tooth is described below? - most have two roots and two canals - root depression mesial and distal with the mesial being deeper - mesial crown cavitation at cervical - bifurcation located in the apical half of the root

Answer 38

maxillary first premolar

Question 39

What teeth are described below? - two roots (mesial and distal) - mesial root is wider faciolingually - three canals (two in mesial root) - mesial root with mesial and distal root depressions - furcation access is located midfacial and midlingual

Answer 39

mandibular first and second molars

Question 40

What teeth are described below? - three roots (mesiobuccal, distobuccal, and lingual) - four canals (two in mesiobuccal) - mesiobuccal root is wider than distobuccal - mesiobuccal root has a mesial and distal depression - furcation access is located midfacial, mesial, and distal

Answer 40

maxillary first and second molars