Brainscape's Knowledge GenomeTM

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


See full index

DS1101 - S1 Y1 > Week 4 - Bacteria and Biofilm > Flashcards

Week 4 - Bacteria and Biofilm Flashcards

1
Q

What are the oral habitats/surfaces

A
  • lips, cheeks, palate
  • Tongue
  • Teeth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Explain lips, cheek and palate as a oral habitat

A

They are:
- Shedding surfaces meaning that they don’t tend to build up a lot of bacteria as they shed the bacteria along with the bacteria constantly
- Keratinised - the hard palate is keratinised which makes it quite difficult for bacteria to attach there so there is only a certain types of bacteria that grow on the hard palate

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

Explain the tongue as a oral habitat

A
  • Highly papillated
  • Reservoir
    Tongue is highly papillated (lots of bumps) where down in the low part of the papilla is a low oxygen environment where the bacteria can hide away in there and then replenish the rest of the mouth when they need to acting as a reservoir for certain types of bacteria
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Explain the teeth as a oral habitat

A
  • Number of surfaces
  • Gingival crevice
  • Non-shedding surface
  • Plaque build up

Teeth is a
non-shedding surface which is why plaque can build up, so bacteria attaches and
bacteria attaches upon that.

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

How does bacteria adhere to surfaces

A

Adherence to a habitat in the oral cavity is due to interactions between a molecule that is found on the bacterium called the adhesion and a molecule on the host surface called a ligand, usually some sort of receptor, which interacts in a lock and key interaction.

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

What are the main oral microbiota

A
  • Streptococci
  • Veillonella
  • Gram-positive Diptheroids (Corynebacterium)
  • Gram-negative anaerobic bacilli
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are biofilms

A

Biofilms are free floating bacteria attached to a solid surface which contains multiple species of bacteria.
They are embedded within an extracellular polysaccharide slime layer which acts as a form of protection as its hard for antibiotics to get through
When nutritional needs re not met in the environment the biofilm will go into a latent state, where the bacteria cell’s aren’t dividing. Cell division will resume when sufficient nutrients are provides.

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

Where do biofilms form

A
  • plaque on teeth
  • Around dental implants
  • Contaminated waterlines
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is dental unit water biofilms

A

Biofilm which forms where water is left to settle in the tubing and ridges of dental equipment.

This contamination with biofilm poses major issues:

  • Infection risk (e.g. pseudomonas)
  • Equipment breakdown from occluding the lines and also corroding metal components
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is pellicle

A

Pellicle are lots of glycoproteins in the saliva which settles on the teeth, its an automatic process and even after brushing they will resettle on the teeth.
Pellicle contains:
- mucins
- Salivary glycoproteins
- minerals
- immunoglobulins
- proline-rich proteins (PRPs)

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

Explain the steps for the development of plaque

A
  1. Pellicle - salivary glycoproteins attach to the tooth enamel,
  2. First pioneer bacteria species naturally present in the oral cavity, (streptococcus mutans, streptococcus sanguinis, Strep gordonii) adhere to the pellicle on the teeth enamel
  3. Once attached the bacteria starts to multiply and produces a slimy, sticky substances called extracellular polymeric substance (extracellular polysaccharide slime layer) which helps them adhere to each other and to the tooth, also has antibacterial characteristics
  4. Secondary colonisers which is more bacteria adheres to the biofilm and various species of bacteria coexist in a structured microbial community. Forms channels which enable the flow of oxygen and nutrients in, and the flow of waste out.

optional

  1. Overtime the plaque can mineralise and harden through the process of calcification. Calcium and phosphate ions from saliva contribute to the formation of a hard, mineralized deposit of the teeth known as dental calculus. Calculus provides a rough surface that makes it even easier for additional plaque to accumulate and attach to.
  2. If plaque is not adequately removed through oral hygiene practices, it can lead to inflammation of the gums, known as gingivitis. If left untreated, gingivitis can progress to periodontitis, a more severe form of gum disease that affects the supporting structures of the teeth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are examples of first pioneer bacteria

A

streptococcus mutans,
streptococcus sanguinis,
Strep gordonii

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

What is the slime layer produced in the formation of plaque and what is its function

A

extracellular polysaccharide slime layer which helps them adhere to each other and to the tooth, also protectsit from antibiotics

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

What are the 3 types of subgingival plaque

A
  • tooth-attached plaque
  • Epithelial-attached plaque
  • Unattached plaque (bacteria not apart of the biofilm)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the most dangerous type of subgingival plaque

A

tooth-attached plaque as it’s detrimental to periodontal tissue

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

What is calculus

A

Calculus is calcified plaque. It develops when dental plaque is not effectively removed through oral hygiene and they undergo calcification where minerals, primarily calcium and phosphate ions present in saliva, are deposited in the plaque. Overtime these minerals harden the plaque, transforming it into dental calculus.

Dental calculus has a rough porous surface which makes it even easier for bacteria to grow and adhere to it.

Dental calculus has to be removed by scaling instruments.

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

How is calculus removed

A

scaling instruments

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

What are the dangers of hard water areas

A

Hard water has a higher concentration of calcium and phosphate salts which causes the calcification of plaque

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

What are the types of calculus

A
  • Supragingival
  • Subgingival
20
Q

What is supragingival calculus

A

Calculus which forms above the gingival margin and is yellowish-white

21
Q

What is subgingival calculus

A

Calculus which forms below the gingival margin on the surface of the root or in periodontal pockets
This calculus is black/dark green

22
Q

What are dental caries

A

Dental caries also known as cavities or tooth decay are localized destructive lesions of the tooth enamel and underlying structures. Dental Caries are an infectious disease, and a major health problem.

23
Q

What is the ecological plaque hypothesis for caries

A
  1. fermentable sugars produce acid
  2. Environmental change - low pH
  3. Ecological shift - mutans strep and lactobacillus
  4. Disease - increased risk of caries
24
Q

Explain the steps in the formation of dental Caries

A
  1. Bacteria within the plaque metabolizes sugars and carbohydrates (from the diet) and as a by product produces acids, particularly lactic acid. These acids lower the pH causing an environmental change resulting in an ecological shift in the certain types of bacteria present.
  2. The acid produced by bacteria can lead to the demineralization of the tooth enamel. Demineralization involves the loss of minerals such as calcium and phosphate from the enamel, making it softer and more susceptible to decay.
  3. With continued acid production and demineralization the enamel erodes and breaks down, leading to the formation of holes in the tooth.
25
Q

What are the 4 risk factors needed for caries to form

A
  1. Tooth - enamel surface
  2. Time -
  3. Bacteria - produces acid which demineralizes the tooth enamel
  4. Diet - diet in high sugars and carbohydrates provide nutrients for the bacteria which produce the lactic acid
26
Q

What are preventive factors for caries

A
  • Maintaining good saliva flow (staying hydrated) as it can help neutralize acids in the mouth, and it can enable repair of the enamel - remineralisation
  • Antibacterial Agents
  • Saliva buffe capacity
  • Reduce sugar and carbohydrate intake
  • Fluoride - fluoride helps strengthen tooth enamel and makes teeth more resistant to acid
  • Dental Sealants - they are protective coating applied to the occlusal surfaces which seal off the deep grooves and pits where bacteria and food particles can accumulate
27
Q

What bacteria cause the creation of caries(2)

A
  • Strep Mutans (found in plaque)
  • Lactobacillus (form in high sugar intake)
    these bacteria produce acid
28
Q

What does ecological shift mean

A

Changing in the dominant bacteria (not changing what type is there just the ratio of how much and which one is there more of)

29
Q

What is the role of saliva to help prevent caries (3)

A
  • Dilutes and eliminates sugars and other dietary components, microorganisms. Patients with low flow rates (xerostomia) have increased risks of caries
  • Buffers pH changes produced by ingestion of foods with a low pH e.g. carbonated drinks, citrus fruit
  • Balances demineralization/ remineralization. Saturated with Ca+2, OH- and PO4
30
Q

What are Periodontal Diseases

A

Periodontal diseases also known as gum diseases are a group of inflammatory conditions affecting the tissues surrounding and supporting the teeth, including the gingiva, bone supporting the teeth and the ligaments that hold the teeth in place. The primary cause of periodontal diseases is the accumulation of dental plaque.

31
Q

What is the early stage of periodontal disease

A

Gingivitis

32
Q

What is Gingivitis

A

Gingivitis is the mildest form/ early stage of periodontal disease and involves the inflammation of the gingiva in response to dental plaque. It is caused by the accumulation of plaque at the gumline, leading to irritation and inflammation. Gingivitis is reversible with proper oral hygiene practices and professional cleaning.

33
Q

What are the symptoms of gingivitis

A

red, swollen gums that may bleed during brushing or flossing

34
Q

What is periodontitis

A

Periodontitis is a more advanced and server form of gum disease. It occurs when gingivitis is untreated and inflammation spreads into ligaments and bones that support the teeth, and there’s a ecological shift from gram positive aerobes to gram negative anaerobes.

35
Q

What does periodontitis cause

A

Periodontitis leads to the formation of periodontal pockets which are spaces that develop between the teeth and gums resulting in gingiva recession and bone loss. This also creates an environment that is highly anaerobic, pH shifts to 7.7.-7.8 enabling proteolytic bacteria to flourish.

36
Q

What are the symptoms of periodontitis

A
  • Red, swollen or tender gingiva
  • Bleeding of the gingiva whilst brushing
  • Pus around the teeth or gingival tissues
    As it progresses:
  • Loose or separating teeth
  • Pain or pressure when chewing
37
Q

What is the condition where there is a dry mouth

A

xerostomina

38
Q

What are the impacts of fluoride

A
  • remineralizers
  • limits bacteria capacity to produce acid
39
Q

What is the condition of a dry mouth

A

Xerostomia

40
Q

Explain the ecological plaque hypothesis for periodontal disease

A
  1. plaque accumulation
  2. Inflammatory response - increased inflammation
  3. Environmental change - high pH, high temperature, change in nutrients, high GCF flow
  4. Ecological shift - predominantly gram negative microflora and obligate anaerobes
41
Q

What are the bacteria which cause periodontists

A

Porphyromonas (P) gingivalis
Tannerella (T) forsythia
Treponema (T) denticola

42
Q

What is the environmental change in the formation of periodontitis

A
  • Low oxygen ( low redox potential)
  • high GCF flow
  • High temperature
  • high pH
  • change in nutrients
43
Q

What are the tissues affected by periodontal disease

A
  • gingiva
  • periodontal ligament
  • alveolar bone (bond connected to the teeth)
44
Q

What are secondary caries

A

the development of new cavities in areas next to existing dental restorations such as fillings, crowns or bridges. These cavities form due to the breakdown of the tooth structure around the margins of the dental restoration leaving the tooth vulnerable to bacterial colonization and acid attack.
These areas are also difficult to clean.

45
Q

Why are older people more prone to developing root caries

A
  • gingival recession exposing roots
  • may also be on medications that affect saliva flow
46
Q

What are the first visual signs of caries

A

White spot lesions

DS1101 - S1 Y1 (63 decks)

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