Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

infection and immunity > plaque & caries > Flashcards

plaque & caries Flashcards

1
Q

What is dental plaque?

A

complex microbial community that forms on tooth surfaces.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What does dental plaque contain?

A

Living, dead, and dying bacteria, their products, and salivary compounds.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is calcified plaque called?

A

Calculus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What surrounds microorganisms in dental plaque?

A

organic matrix.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What do communities of microorganisms in dental plaque form?

A

biofilm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How does the biofilm in dental plaque affect microorganisms?

A

Protect from host defenses and antimicrobial agents, making them more pathogenic.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How many microorganisms are typically found in dental plaque?

A

Hundreds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What system do microorganisms in dental plaque use to adapt to their environment?

A

A communication system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Do microorganisms in dental plaque share resources and activities?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is dental plaque a key player in?

A

development of caries and periodontal disease.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How can plaque control impact dental health?

A

can arrest and prevent dental caries and periodontal diseases.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Why is plaque control especially important in compromised patients?

A

Poor plaque control can have more serious systemic consequences.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What species make up a large proportion of the resident oral flora?

A

Viridans streptococci

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Which species of Streptococcus is a major species found in saliva?

A

Streptococcus salivarius (108/ml).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is a pellicle?

A

An acidic glycoprotein film thatf orms on a freshly cleaned tooth surface after contact with saliva

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Which Streptococcus species colonize the pellicle on a freshly cleaned tooth surface?

A

S. oralis
S. mitis
S. gordonii
S. sanguinis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is dental plaque made of?

A

A firmly attached growth of bacteria + matrix (biofilm).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the two types of dental plaque?

A

Supragingival plaque
Subgingival plaque

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the role of early colonizers in dental plaque?

A

the initial predominant bacteria that colonize the pellicle surface.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How do early colonizers adhere to the pellicle surface?

A

Adhesins on the bacterial surface.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What type of bacteria are early colonizers in dental plaque? (gram type & aerobe)

A

Gram-positive facultative anaerobic bacteria.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Which bacteria species make up over 80% of the initial biofilm?

A

Actinomyces species
Oral streptococci.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What type of bacteria are typically found in supragingival plaque? (gram type and aerobe)

A

Gram-positive facultative anaerobic bacteria.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What type of bacteria are found in subgingival plaque? (gram and aerobe)

A

Including Gram-negative anaerobic bacteria, more complex flora.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What happens when plaque continues to form?

A

It attracts other bacteria to adhere to the bacterial matrix.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Dysbiosis is?

A

“the transition of the polymicrobial community from largely gram-positive commensal microbes to a gram-negative enriched inflammogenic community.”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What type of bacteria are secondary colonizers in dental plaque? (gram and aerobe)

A

Gram-negative anaerobes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Which bacteria are considered secondary colonizers in dental plaque?

A

Prevotella intermedia
Capnocytophaga species
Fusobacterium nucleatum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Which bacteria are considered late colonizers in dental plaque?

A

Porphyromonas gingivalis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

How does Porphyromonas gingivalis (late colonizers) contribute to dental plaque?

A

It adheres to earlier colonizers. (Gram-positive bacteria)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Why is Porphyromonas gingivalis significant in oral health?

A

keystone pathogen in the progression of periodontitis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is the primary component of dental plaque?

A

Proliferating bacteria (70%, about 700 different species).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What host cells are found in dental plaque?

A

Epithelial cells, macrophages, and leukocytes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What makes up the adherent intercellular matrix in dental plaque?

A

Food reservoir and cement binding organisms to each other and to surfaces.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What other microorganisms might be found in dental plaque?

A

Mycoplasma, fungi, protozoa, and viruses.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Does the microbial composition of plaque vary between individuals?

A

Yes, it varies. Some people are fast plaque formers, while others form plaque slowly.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

How does the inorganic content of early plaque compare to calculus?

A

Early plaque has low inorganic content, while calculus has high inorganic content.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What inorganic components are found in dental plaque?

A

Calcium, phosphorus, and small amounts of magnesium, potassium, and sodium.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What is the biofilm matrix in dental plaque composed of?

A

Polysaccharides, proteins, and other compounds.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What is Stage 1 of dental biofilm formation?

A

Pellicle formation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What happens in Stage 2 of dental biofilm formation?

A

Bacterial attachment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What occurs in Stage 3 of dental biofilm formation?

A

Colonization and multiplication, with the development of pathogenic potential.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What happens in Stage 4 of dental biofilm formation?

A

Growth, with an increase in mass and thickness.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What occurs in Stage 5 of dental biofilm formation?

A

Maturation, with the intermicrobial matrix connecting colonies.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

When do secondary colonizers attach in plaque formation?

A

After ~1-2 days of plaque accumulation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What type of bacteria are late colonizers in plaque formation?

A

Gram-negative bacteria.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

When do late colonizers attach in plaque formation?

A

After ~1 week of plaque accumulation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What is the first step in supragingival plaque development?

A

Pellicle formation (adsorption of salivary proteins to the tooth surface).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What happens after pellicle formation in supragingival plaque development?

A

Transition into dental plaque, starting with colonization by gram-positive cocci (primary colonizers).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What is present during the early stages of dental plaque development?

A

Small numbers of epithelial cells and polymorphonuclear leukocytes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What occurs after the colonization of primary colonizers?

A

Proliferation of bacteria.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What happens after bacterial proliferation in plaque development?

A

Aggregation of bacteria (secondary colonizers).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What is the final step in the development of supragingival plaque?

A

Biofilm formation and eventual detachment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

What occurs after colonization by gram-positive cocci in supragingival plaque development?

A

Proliferation, aggregation, and colonization by gram-negative rods.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

What is the first step in plaque development?

A

Microbial adherence.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Why is microbial adherence important in plaque development?

A

prerequisite for colonization and the initial step in infection and tissue invasion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

What type of bacteria are present in early plaque?

A

Gram-positive facultative bacteria, associated with health.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What are some host cleansing factors that challenge microbial adherence?

A

Mucosal barrier, desquamation, immune mechanisms, and resident commensal flora.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

How do salivary factors challenge microbial adherence?

A

help prevent microbial attachment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

What happens during the shift in plaque composition?

A

plaque shifts from gram-positive bacteria to more complex bacteria.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

What role do physical factors play in challenging microbial adherence?

A

Movements of the tongue and mucosal turnover (desquamation) help remove microbes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

What type of bacteria are present in mature plaque?

A

Gram-negative anaerobic bacteria, which are associated with disease.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

What does subgingival plaque development depend on?

A

Supragingival plaque.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

What happens during supragingival plaque-associated inflammatory changes?

A

Edema and gingival enlargement occur.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

How does gingival enlargement affect subgingival plaque development?

A

increases the capacity of the subgingival area for bacterial colonization.

66
Q

How does an enlarged subgingival area affect bacteria?

A

protects the bacteria from oral cleansing.

67
Q

What happens to crevicular fluid flow during subgingival plaque development?

A

increases

68
Q

What effect does increased pocket epithelial cell turnover have?

A

contributes to the development of a new bacterial niche.

69
Q

What makes the new subgingival niche favorable for anaerobic bacteria?

A

rich in crevicular fluid, desquamated epithelial cells, bacterial end products, and has a low oxidation-reduction potential.

70
Q

What happens as subgingival organisms grow?

A

leads to the development of pathology.

71
Q

What is the composition of tooth-associated plaque?

A

Mainly gram-positive filamentous bacteria with some gram-negative cocci and rods.

72
Q

What is tooth-associated plaque associated with?

A

Calculus formation, root caries, and root resorption.

73
Q

What is the structure of epithelium-associated plaque?

A

Loosely adherent structure.

74
Q

What are the two layers in epithelium-associated plaque?

A

One layer is in contact with epithelial cells, and the other is loose in the sulcular or pocket lumen.

75
Q

What type of bacteria is mainly found in epithelium-associated plaque?

A

Mainly gram-negative rods and cocci.

76
Q

What does epithelium-associated plaque contribute to?

A

development of periodontal disease.

77
Q

When is connective tissue-associated plaque observed?

A

periodontal disease

78
Q

How does bacteria behave in connective tissue-associated plaque?

A

Bacteria penetrate through the pocket epithelium wall and basal lamina into the connective tissue.

79
Q

In which conditions is connective tissue-associated plaque demonstrated?

A

in acute ulcerative gingivitis, advanced periodontitis, and aggressive periodontitis.

80
Q

What is dental calculus?

A

adherent calcified or calcifying deposit on teeth

81
Q

What is the primary inorganic content in supragingival calculus?

A

70-90% inorganic salts, mainly calcium phosphate, with calcium carbonate and magnesium phosphate.

82
Q

What is the main component of dental calculus?

A

mineralized bacterial plaque.

83
Q

What is Supragingival calculus?

A
  • white or whitish-yellow
  • results from poor hygiene
    -lack of adequate masticatory function
  • tooth malposition
84
Q

What are the two main categories of dental calculus?

A

Supragingival and Subgingival.

85
Q

What is Subgingival calculus?

A
  • found below the gingival margin
  • usually in periodontal pockets, - dark-brown or greenish-black, dense, hard
86
Q

What are the four crystal forms found in supragingival calculus?

A

Hydroxyapatite [58%]
Magnesium whitlockite [21%]
Octacalcium phosphate [21%]
Brushite [9%]

87
Q

How does the composition of subgingival calculus differ from supragingival calculus?

A

Subgingival has more inorganic (hydroxyapatite) content than supragingival

88
Q

How does dental calculus contribute to periodontal disease?

A

It provides a surface for bacteria, keeping plaque close to the gingiva and creating areas difficult to clean.

89
Q

What is the composition of supragingival and subgingival calculus?

A

Both consist of mineralized plaque, always covered by an unmineralized bacterial layer.

90
Q

What did epidemiologic studies show about the relationship between dental calculus and periodontal disease?

A

strong correlation between the presence of calculus and the progression of periodontal disease.

91
Q

How can dental plaque formation be prevented?

A

Through daily hygiene, bi-annual professional cleanings, and education (oral hygiene instructions).

92
Q

What types of bacteria are typically found in normal oral microflora?

A
  • Non-mutans streptococci (e.g., salivarius group) on root surfaces,
  • mitis group in pits and fissures
  • small number of mutans group streptococci.
93
Q

How does an alteration in oral microflora contribute to caries development?

A

A shift in the balance can result in an increase in caries-inducing organisms, such as S. mutans and Lactobacillus.

94
Q

What causes the localized destruction of the tooth in dental caries?

A

bacterial fermentation of dietary carbohydrates, leading to the loss of hydroxyapatite crystals in the tooth.

95
Q

Which bacteria are considered key contributors to caries?

A

S. mutans and Lactobacillus

96
Q

What are the key factors in the development of dental caries?

A
  • susceptible tooth surface
  • nature of saliva flow
  • plaque bacteria
  • consumption of fermentable carbohydrates.
97
Q

T or F: caries is a multifactorial disease

A

True

98
Q

When does enamel caries typically occur?

A

early in life (before age 20), and then stabilizes over time.

99
Q

When does root caries typically occur?

A

later in life, often due to gingival recession and exposure of the root cementum.

100
Q

Which bacteria are commonly found on smooth enamel surfaces?

A

Streptococcus mutans and Streptococcus salivarius

101
Q

which bacteria is most commonly involved in caries on pits and fissures?

A

S. mutans

102
Q

Which types of bacteria dominate the microbiota of dentine?

A

Anaerobes, such as Lactobacilli and Actinomycetes species

103
Q

Which bacteria are prevalent in root caries after age 35?

A

Anaerobes, particularly Actinomycetes species

104
Q

What is enamel made of?

A

95% calcium phosphate salts, primarily in the form of hydroxyapatite. It’s the most highly mineralized structure in the human body.

105
Q

What does it mean that enamel is the most highly mineralized structure in the human body?

A

extremely hard and resistant to wear, durable

106
Q

What types of acids are produced by bacteria that affect enamel?

A

Lactobacillus produce lactic acid, and other bacteria like Streptococcus produce acids that break down enamel by demineralizing it.

107
Q

How does acid break down enamel?

A

diffuses into enamel, breaking down hydroxyapatite crystals. This results in enamel becoming porous, and the spaces fill with fluid

108
Q

What occurs when enamel becomes weak?

A

allows bacteria to invade deeper into the tooth, further contributing to decay.

109
Q

What is the acid theory of caries?

A

suggests that acids produced by bacteria in plaque lead to demineralization of the enamel, which causes tooth decay.

110
Q

What is demineralization?

A

process where enamel loses hydroxyapatite crystals

111
Q

What is remineralization?

A

process of restoring hydroxyapatite crystals

112
Q

What is the first stage in the development of caries?

A

Primary lesion (incipient lesions) - reversible step, can remineralize.

113
Q

What happens in the second stage of caries development?

A

Development of cavity, where demineralization progresses into actual tissue loss.

114
Q

What occurs in the third stage of caries development?

A

Spread into dentine and destruction of dental pulp, affecting deeper tissues.

115
Q

What is the final stage in the development of caries?

A

Development of periapical infection, leading to possible abscess formation.

116
Q

What role do bacteria play in caries development?

A

contribute to the formation of caries.

117
Q

What is the role of the host in the development of caries?

A

susceptible tooth surface and saliva are key factors.

118
Q

How does diet influence the development of caries?

A

Mainly fermentable carbohydrates are the primary dietary factor that leads to caries.

119
Q

What is the significance of time in caries development?

A

Time is a key factor as continuous exposure to risk factors allows caries to develop.

120
Q

Why are some tooth areas more susceptible to caries?

A

Differences in mineral content (e.g., fluoride).

121
Q

How does saliva help prevent caries?

A

Mechanical washing, neutralizes acids, and provides calcium and phosphorus for remineralization.

122
Q

What antibacterial enzymes are found in saliva?

A

Lysozyme, lactoperoxidase, and lactoferrin.

123
Q

What role does diet play in caries development?

A

Fermentable carbohydrates increase caries risk.

124
Q

How does sucrose diffuse into dental plaque?

A

its soluble and easily diffuses into the dental plaque.

125
Q

What does streptococci produce when sucrose is present?

A

insoluble glucan

126
Q

What role does glucan play in caries development?

A

nutritional source, forms a matrix, and facilitates microbial adhesion, promoting caries

127
Q

What is a prerequisite for the development of dental caries?

A

Dental plaque bacteria

128
Q

What is the most effective Streptococcus species causing caries?

A

Streptococcus mutans

129
Q

What ability does S. mutans have in sites with a low pH?

A

can initiate and maintain growth and continue acid production (primarily lactic acid).

130
Q

What does acidogenic mean in relation to S. mutans?

A

It produces acid.

131
Q

What does aciduric mean in relation to S. mutans?

A

It survives in low pH.

132
Q

What is the optimal pH range for the growth of S. mutans?

A

pH 4.5 to 5.0

133
Q

How low of a pH can S. mutans survive for brief periods?

A

pH 2.5

134
Q

What does acidophilic mean in relation to S. mutans?

A

It grows best in acidic conditions.

135
Q

Where are Lactobacillus bacteria commonly found in relation to caries?

A

lesions on enamel and root surfaces.

136
Q

What does a high number of Lactobacillus in saliva indicate?

A

correlates with the presence of caries.

137
Q

What does it mean that Lactobacillus is aciduric (acid-tolerant)?

A

It can initiate and maintain growth at low pH.

138
Q

What acid do Lactobacillus bacteria produce, and under what conditions?

A

produce lactic acid in conditions below pH 5 by fermenting carbohydrates to acids.

139
Q

True or False: lactobacillus may not be involved in the initiation of dental caries but are involved in the progression of caries deep into the enamel and dentin

A

True

140
Q

Lactobacillus ________ the growth of mutans streptococci in culture and has been used as a ______________.

A

inhibits; probiotic

141
Q

What is the source of nutrients for microorganisms in plaque metabolism?

A

Saliva

142
Q

How much can carbohydrate levels increase after a meal?

A

1,000-fold.

143
Q

3 levels of regulatory mechanisms:

A
  1. Transport of sugar into organism
  2. The glycolytic pathway
  3. Conversion of pyruvate into metabolic end-products
144
Q

what ways can caries be prevented?

A

1) reduction of sugar intake
2) fluoridation
3) pit and fissure sealants
4) control of cariogenic plaque flora
5) replacement of cariogenic bacteria

145
Q

At what pH does enamel demineralization begin?

A

Below 5.5.

146
Q
A
147
Q
A
148
Q
A
149
Q
A
150
Q
A
151
Q
A
152
Q
A
153
Q
A
154
Q
A
155
Q
A
156
Q
A
157
Q
A
158
Q
A
159
Q
A
160
Q
A
161
Q
A
162
Q
A

infection and immunity (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions