Dental Plaque Specific Bacteria Theory

Question 1

Requires 3 Factors + Time

Answer 1

Tooth
Bacteria
Substrate (fermentable carbohydrates)

Question 2

Sometimes referred to as the ___ ___because time is often considered to be the fourth factor. It depends on the author who is reporting or running the study.

Answer 2

Caries Quad

Question 3

Infectious Disease Process can be transmitted from person to person true or false

Answer 3

true

Question 4

Multi-species – the mouth is host to 150-800 different species of bacteria at any one time
Collectively called _____ – this refers to the groups, or colonies of bacteria
Involves destruction of mineralized tooth surfaces (enamel & dentin)

Answer 4

biofilm

Question 5

The 3 major players of the infectious disease process

Answer 5

Main Player- streptococcus mutans

Main Player- lactobacillus acidophilus
Actinomyces israelii

Question 6

Plays a role in root caries

Answer 6

Actinomyces

Question 7

What is plaque formation

Answer 7

Microbial biofilm adapted to its environment

Question 8

Plaque involves 2 different types of adhesion to surfaces

Produces extracellular coatings & ___ ____ to help more bacteria adhere to biofilm

Answer 8

1. Physiochemical
2. Biochemical

surface fibrils

Question 9

Plaque requires what kind of removal

Answer 9

mechanical

Question 10

Plaque Biofilm as an Infectious Disease:

other Infectious diseases:

Answer 10

• Heterogenous
• Community “Whatever benefits the whole”
• Higher Resistance
• Fluctuations in cell structure

Other:

• Homogeneous
• Non-community (in it to win it, its all about me)
• lowered resistance

Question 11

• The _____ means that the group of bacteria has a higher resistance to the therapeutic agents that we use. Where as, in an infectious disease that has a single bacterium as the culprit means that the resistance to “attack” is much lower.

Answer 11

heterogeneity

Question 12

There is communication between bacteria in the plaque community. This means that if one area is being “attacked” the other areas can ”__ ___” and fortify the area of attack. This makes bacterial plaque difficult to kill!

Answer 12

send help

Question 13

Plaque Biofilm is

Naturally acquired from:

Composed of:

Answer 13

• Food
• Human Contact
• Pets
• Atmosphere

Composed of:
Salivary components
Microorganisms (organized into communities
Intracellular matrix

Question 14

Cell-to-Cell Communication

Answer 14

• Micro-climates
• Resistance to exogenous antimicrobial agents
• Mechanical oral hygiene practices are critical

Question 15

Prior to Tooth Eruption:
____ pellicle
- Exists prior to tooth

Answer 15

Subsurface

Question 16

Prior to Tooth Eruption:
____ pellicle
- Exists prior to tooth ___

Consists of:

Considered Endogenous

Answer 16

Subsurface
Eruption
Reduced enamel epithelium
Basal Lamina

Considered Endogenous

Question 17

The tooth erupted. Now what?

Answer 17

The REE is digested by salivary and bacterial enzymes

Within seconds a thin microscopic coating of salivary components become absorbed onto the tooth surface

Question 18

The tooth erupted. Now what?

Answer 18

The REE is digested by salivary and bacterial enzymes

Within seconds a thin microscopic coating of salivary components become ADSORbed onto the tooth surface

Question 19

ADSORPTION
vs
Absorbtion

Answer 19

ADSORPTION is the adherence of one substance to a dissimilar substance

Absorption is one substance being taken up by another

Question 20

Acquired Pellicle

Answer 20

Acellular
Contains:
Salivary glycoproteins
Receptor sites
Fills MILLIONS of microscopic tooth voids
Provides nutrients
Takes about one week to fully reform after removal from prophylaxis procedure
Adds a protective quality for the teeth& fills in those small nooks and crannies

Question 21

Acquired Pellicle are Acellular meaning

Answer 21

no cells no bacteria.

Question 22

Plaque uses ___ pellicle to “stick to the teeth”

Answer 22

acquired

Question 23

The pellicle is made up of salivary glycoproteins which are responsible for

Answer 23

innate immunology of the oral cavity, they bind calcium phosphate ions to help remineralize teeth, provide a food source for both beneficial and harmful bacteria, and contain alpha amylase to help the process of polysaccharide breakdown. As you can see, it is a complex layer that coats each tooth.
To clarify, after the pellicle is removed by a professional prophylaxis, it begins to re-form within seconds. However, it is not fully formed and mature for a full week.

Question 24

Plaque Components

Answer 24

70-80% bacteria

20-30% polysacchrides and glycoproteins

Question 25

The polysaccharides help ensure a continuous food source in the event of “starvation” (when we don’t eat for a long period of time or when we eat foods that do not feed the bacteria) In dental terms, the bacterial glycoproteins are ____ _____ located on the cell membrane that help other bacteria to adhere to the plaque biofilm. And they also help the cells to communicate with each other. It’s like a telephone cord to the other areas of the bioflilm!

Answer 25

carbohydrate chains

Question 26

Formation of Dental Plaque Bacteria tend to accumulate on teeth in sheltered undisturbed environments. But they also accumulate on:

Answer 26

- Pits and Fissures - Interproximal surfaces - Gingival sulcus Also - Lips - Cheek - Palate - Tongue - Restorative Overhangs May find plaque in areas you wouldnt normally find due to dry mouth

Question 27

Explain the formation of plaque in detail after a prophylaxis

Answer 27

Dental pellicle forms within seconds of prophylaxis In about 2 hours, bacteria loosely binds to pellicle (adsorption) Bacteria multiples exponentially and spreads Microcolonies form within the plaque matrix Streptococci (multiple strains) secrete a protective slime layer Maturation of the biofilm colonies Microcolonies join to form larger, more complex, mutually beneficial groups (biofilm!) Development of a primitive circulatory system

Question 28

Able to adhere to acquired pellicle Generally NOT pathogenic (S. sanguis to S. mutans) Normally aerobic or facultative anaerobic Gram positive Primarily made up of cocci & short rods Provides substrate microclimate for…

Answer 28

Primary Colonizers

Question 29

Colonize on an EXISTING bacterial layer Much more pathogenic (Lactobacillus) Anaerobic (oxygen can only penetrate plaque to 0.1mm) Usually gram negative (except for Lactobacillus) Made up of rods, filamentous forms, spirochetes, etc.

Answer 29

Secondary Colonizers

Question 30

Colonization Competition: Bacteria compete for sites | Host responds to the presence of pathogenic bacteria with:

Answer 30

- Immunoglobulins (antibodies) - Enzymatic lysozyme - Complement proteins These host proteins originate from saliva and crevicular fluid

Question 31

Beneficial and pathogentic competing for sites. Explain the process and how it relates to perio?

Answer 31

We are talking and focusing a lot on the pathogenic bacteria. But there are a large number of beneficial bacteria that are also present. These beneficial and harmful bacteria compete for sites on the pellicle and in the plaque biofilm itself. The best case scenario is that the majority of the plaque biofilm is beneficial bacteria. As the numbers of the pathogenic bacteria increase, the number of beneficial bacteria decreases. Thus, caries (and perio) risk goes up! And, most (if not all) of the beneficial bacteria are the cocci and short rod, gram positive, aerobic bacteria. The pathogenic bacteria tend to be anaerobic in some form (facultative or otherwise), rods, spirochetes, motile, etc. Once the host detects the pathogenic bacteria, the body responds through a variety of “seek and destroy” measures to remove the pathogenic bacteria. The body produces immunoglobulins from WBC that serve to identify and mark a non-host cell for destruction, releases phagocytic cells that provide lysozyme to “dissolve” the bacterial cell walls, and initiates the inflammatory response through complement proteins. The role of inflammation is to bring more antibodies, more WBC, more immunoglobulins to the area until the offending pathogens have been removed.

Question 32

long columns of bacteria seen in the picture above. formed through the competitive colonization that was mentioned earlier and results in the entombment of the bacteria nearest the enamel by the IPM.

Answer 32

Palisades

Question 33

Palisades form through competitive colonization _______ occurs by an intercellular plaque matrix, more superficial bacteria, and saliva itself

Answer 33

Entombment

Question 34

collection of dead bacterial cells, sloughed-off host cells from the oral cavity, blood cells, and food particles.

Answer 34

Materia alba

Question 35

2 different theories of plaque

Answer 35

Non-specific plaque theory | Specific plaque theory

Question 36

- States that it is the number of all bacteria within plaque that has a positive, direct correlation with the caries rate - Groups all bacteria of the oral cavity together - Ignores the individual characteristics of each bacterium

Answer 36

Non-Specific Plaque Theory

Question 37

- States that it is specific bacteria within plaque whose numbers influence the caries rate – not all bacteria - Considers individual genus and species of bacterium separately - Considers the defining characteristics of each bacterium

Answer 37

Specific Plaque Theory

Question 38

Consumes acidic wastes and turns them into less acidic waste products xtra fact: , in terms of caries, is considered to be a beneficial bacterium. It helps to regulate the metabolic waste products of bacterium such as S. mutans and by using it as a food source. Its own waste by-product is a less acidic material.

Answer 38

Veillonella

Question 39

Formerly known as S. sanguis Keeps acid production low Direct competitive colonizer Has links to infective endocarditis

Answer 39

Streptococcus Sanguinis

Question 40

What are the 2 good bacteria

Answer 40

Veillonella | Streptococcus Sanguinis

Question 41

2 Bad bacteria

Answer 41

Streptococcus mutans | Actinomyces israelii

Question 42

- Produces lactic acid from glucose - Highly acidogenic and therefore, acid-tolerant - Associated with advanced caries & carious dentin

Answer 42

Lactobacillus acidophilus

Question 43

- Kicks beneficial bacteria off the teeth and takes their place - Disengages the gums - Causative agent in antibiotic resistance

Answer 43

Porphyromonas gingivalis

Question 44

2 Aciduric Bacteria

Answer 44

Strep mutans - First cariogenic bacteria that are laid down - High amounts of lactic acid as a result of metabolic wastes, which attracts… Lactobacillus - Lowers the pH - Displaces Strep mutans - Continues tooth demineralization

Question 45

Plaque require what energy source

Answer 45

Fermentable carbohydrates

Question 46

Plaque: Aciduric microorganisms produce:

Answer 46

-Acid -Intracellular polysaccharides (provide energy) -Extracellular polysaccharides (provide an anchor point) /Glucans (dextran) /Fructans (levan)

Question 47

Plaque Exist Under Adverse Conditions

Answer 47

``` pH Temperature Nutrition Competing organisms Host inflammatory response Anaerobic conditions/oxygen competition ```