Midterm 1

Question 1

critical pH for enamel (hydroxyapatite)

Answer 1

5.5

Question 2

critical pH for dentin

Answer 2

6.2

Question 3

critical pH for enamel (hydroxyfluorapatite)

Answer 3

4.5

Question 4

tooth demineralization as a result of the caries process

Answer 4

caries lesion (aka carious lesion aka cavity)

Question 5

a caries lesion in any surface of the anatomic tooth crown

Answer 5

coronal caries

Question 6

a caries lesion not adjacent to an existing restoration or crown

Answer 6

primary caries

Question 7

a caries lesion adjacent to an existing restoration, crown, or sealant

Answer 7

secondary caries

Question 8

other term used for secondary caries is _____

Answer 8

caries adjacent to restorations and sealants (CARS)

Question 9

biofilm is composed mostly of ____, their ____, ____ and _____

Answer 9

bacteria; byproducts; extracellular matrix; water

Question 10

non-pathogenic bacterial plaque: acquired ____ forms and is composed of ____ and is ____

Answer 10

pellicle; salivary proteins; cell free

Question 11

role of pellicle

Answer 11

protects (IgA, IgG, lysozymes)
Reduce friction
Remineralization

Question 12

both acidic and basic proteins that adsorb ___ and ____ ions

Answer 12

calcium; phosphate

Question 13

surface of noncavitated enamel lesions has ____ appearance

Answer 13

“punched out”

Question 14

micro-environmental habitats assoc. with host health are generally ____, near ____ in pH, and ____ in oxidation-reduction potential

Answer 14

aerobic; neutrality; positive

Question 15

predominant species in non-carious teeth

Answer 15

S. sanguis

Question 16

environmental conditions within plaque of non-carious teeth

Answer 16

aerobic, pH 5.5, oxidation-reduction negative

Question 17

predom species in enamel caries

Answer 17

S. mutans

Question 18

environmental conditions within plaque of enamel caries

Answer 18

anaerobic
pH < 5.5
oxidation-reduction negative

Question 19

predom species in dentin caries

Answer 19

S. mutans and lactobacillus

Question 20

conditions within plaque of dentin caries

Answer 20

anaerobic
pH < 5.5
oxidation-reduction negative

Question 21

predom species in root caries

Answer 21

actinomyces

Question 22

tooth habitats for cariogenic biofilm not protected by the surface shedding mechanisms (continual replacement of _____) used throughout remainder of _____

Answer 22

epithelial cells; alimentary canal

Question 23

tooth habitats for cariogenic biofilm covered with pellicle of precipitated _____, ____, and _____

Answer 23

salivary glycoproteins; enzymes; immunoglobulins

Question 24

ideal surface for attachment of many oral ____

Answer 24

streptococci

Question 25

if undisturbed, biofilm builds up to sufficient depth to produce an ____ environment adjacent to tooth surface

Answer 25

anaerobic

Question 26

tooth habitats favorable for harboring pathogenic biofilm (caries)

Answer 26

• pits and fissues
• smooth surfaces gingival to proximal contacts; cervical third of facial and lingual of clinical crown
• root surfaces near cervical line
• subgingival areas

Question 27

caries originating on the ____ is alarming because it has ____ progression, is often ____, it is closer to the ____, and it is more ____

Answer 27

root; rapid; asymptomatic; pulp; difficult to restore

Question 28

salivary protective mechanisms that maintain the normal oral flora and tooth surface integrity include ____, _____, ____, and _____

Answer 28

bacterial clearance; direct antibacterial activity; buffers; remineralization

Question 29

antibacterial enzymes in saliva

Answer 29

• lactoperoxidase
• lysozyme
• lipases
• agglutinins

Question 30

non-enzymes in saliva

Answer 30

• lactoferrin
• IgG/A
• Mucins

Question 31

adults produce ____ of saliva a day

Answer 31

1-1.5 L

Question 32

noncavitated enamel caries when hydrated look ____ and when dry look ____

Answer 32

translucent; opaque

Question 33

inactive enamel caries are ___ but ____

Answer 33

hard; rough

Question 34

active enamel caries are ____

Answer 34

soft

Question 35

____ and ____ should only be restored for esthetics at pt request

Answer 35

hypocalcified enamel; inactive enamel caries

Question 36

only _____ require immediate restoration or therapeutic treatment of microbes (saliva rinses, diet restrictions, and fluoride varnish)

Answer 36

active caries

Question 37

the 3 clinical sites for caries initiation

Answer 37

• pits and fissures
• smooth enamel surfaces
• root surfaces

Question 38

enamel caries

Answer 38

• hypocalcified enamel
• white spot lesion (noncavitated enamel caries lesion)
• cavitated enamel lesion (active caries)
• remineralized enamel lesion (inactive caries)

Question 39

developmental white spot; same wet or dry; do not restore unless for esthetics

Answer 39

hypocalcified enamel

Question 40

disappears when wet; chalky white when dry

Answer 40

white spot lesion (noncavitated enamel)

Question 41

proximal lesions into dentin; can not remineralize, must be restored

Answer 41

cavitated enamel lesion (active caries)