Biofilm

Question 1

interactions involved in the formation of biofilm 1-5

Answer 1

formation of a pellicle
bacterial multiplication and colonization
biofilm growth and maturation
matrix formation
bacteria attach to the pellicle

Question 2

t/f: dental caries and gingival and periodontal infections are not caused by microorganisms in microbial or dental biofilms

Answer 2

false

are caused by microorganisms found in microbial or dental biofilm

Question 3

t/f:

cleansing of debris from about fixed prostheses and orthodontic appliances is an important part of oral sanitation

Answer 3

true

Question 4

t/f:

the hard deposits are acquired pellicle or cuticle, dental biofilm, materia alba, and food debris

Answer 4

false

soft deposits are…

Question 5

t/f:

the soft deposits on teeth are dental calculus

Answer 5

false

the hard deposits on…

Question 6

t/f:

the incipient carious lesion begins as visible demineralization

Answer 6

false

begins as subsurface demineralization

Question 7

t/f:
aquired pellicle is composed primarily of glycoprotiens from the saliva, which are selectively absorbed by the hydroxyapatite of the tooth surface

Answer 7

true

Question 8

t/f:

the unstained pellicle is readily visible.

Answer 8

false

pellicle is clear, translucent, insoluble, and not readily visible until disclosing agent has been applied

Question 9

t/f:

the probability of the development of dental caries and/or gingivitis increases as the number of microorganisms decrease

Answer 9

false

number of microorganisms increase

Question 10

t/f:

gingivitis is clinically evident within 2 to 3 days when biofilm is left undisturbed on the tooth surface

Answer 10

false

evident within 2 to 3 weeks

Question 11

t/f:

subgingival biofilm results from the apical proliferation of microorganisms from supragingival biofilm

Answer 11

true

Question 12

t/f:

the flora of the subgingival biofilm does not differ from that of the supragingival biofilm

Answer 12

false

subgingival bifilm does differ

Question 13

t/f:

the biofilm attached to the tooth surface is associated with calculus formation, root caries, and root resorption

Answer 13

true

Question 14

t/f:
between the layers of attached biofilm are many motile, gram-negative organisms. these are considered part of the attached biofilm

Answer 14

false

considered part of free floating/unattached

Question 15

t/f:
loosely attached to the pocket epithelium are many gram-negative microorganisms and numerous white blood cells. these make up the epithelium-associated biofilm

Answer 15

true

Question 16

t/f:

microbial biofilm plays a major role in the initiation and progression of both dental caries and periodontal diseases

Answer 16

true

Question 17

t/f:
surface pellicle is continuous with subsurface pellicle, which is embedded in the tooth structure, particularly where the tooth surface is partially demineralized

Answer 17

true

Question 18

when stained with a disclosing agent, unstained pellicle appears thin, with a pale staining that contrasts with the thicker, darker staining of dental biofilm

Answer 18

true

Question 19

t/f:
the concentration of fluoride in biofilm is higher when fluoridated water is used, and it increases after professional topical applications of fluoride and the use of fluoride-containing dentifrices and mouthrinses

Answer 19

true

Question 20

t/f:

carbohydrates contribute to the adherence of microorganisms to each other and the teeth

Answer 20

true

Question 21

t/f:
the acquired pellicle begins to form within hours after all external material has been removed from the tooth surfaces with an abrasive

Answer 21

false

form within minutes

Question 22

t/f:

subgingival biofilm contains proteins from gingival sulcus fluid

Answer 22

true

Question 23

t/f:

general oral cleanliness is not influenced by the removal of dental biofilm deposits

Answer 23

false

cleanliness is influenced by

Question 24

t/f:
dental caries is a disease of the dental calcified structures (enamel, dentiin, and cementum) that is characterized by demineralization of the mineral components and dissolution of the organic matrix

Answer 24

true

Question 25

t/f:

the number of microorganisms is higher in subgingival biofilm than in supragingival biofilm

Answer 25

true

Question 26

size and shape are affected by friction of tongue, cheeks, and lips

Answer 26

supra

Question 27

main source of nutrients for bacterial proliferation is gingival sulcus fluid

Answer 27

sub

Question 28

coronal to the margin of the free gingiva

Answer 28

supra

Question 29

may become thicker as the diseased pocket wall becomes less tight

Answer 29

sub

Question 30

early biofilm; primarily gram positive cocci

Answer 30

supra

Question 31

heaviest collection on areas not cleaned daily by the patient

Answer 31

supra

Question 32

found on the cervical third, especially facial surfaces, the lingual mandibular molars, and proximal surfaces

Answer 32

supra

Question 33

down growth of bacteria from supragingival biofilm

Answer 33

sub

Question 34

diseased pocket; primarily gram-negative, motile, spirochetes, rods

Answer 34

sub

Question 35

sources of nutrients for bacterial proliferation are saliva and ingested food

Answer 35

supra

Question 36

made up of three layers

Answer 36

sub

Question 37

the structure is an adherent, densely packed microbial layer over pellicle on the tooth surface

Answer 37

supra

Question 38

sequence of events for demineralization and dental caries

Answer 38

biofilm in oral cavity
cariogenic food stuff eaten
fermentable carbohydrate taken into biofilm
acid forms immediately
pH of bioflim drops
frequent exposure of tooth surface to acid
demineralization occurs
white spot lesions; incipient lesions formed
dental caries occurs