Dental Plaque Short Question and Answers

Question 1. Specific plaque hypothesis.
Answer:

• The specific plaque hypothesis states that not all plaque is pathogenic and its pathogenicity depends on the presence of certain specific microbial pathogens in plaque
• Specific microorganisms responsible for periodontal diseases release certain damaging factors called virulence factors which lead to host tissue destruction

Example: A.a. contains causes aggressive periodontitis

Question 2. Define dental plaque.
Answer:

• It is soft deposits that form biofilm adhering to the tooth surface or other hard surface in the cavity including removable and fixed restoration

Question 3. Composition of dental plaque.
Answer:

1. Micro-organisms:

• Bacteria
• Mycoplasm
• Fungi
• Protozoa
• Virus

2. Intracellular matrix:

1. Organic:
   • Carbohydrates
   • Glycoproteins
   • Lipids
2. Inorganic:
   • Calcium
   • Phosphorous
   • Magnesium
   • Potassium
   • Sodium

Question 4. Difference between Supragingival and Subgin. It is for the identification of causative agents given Plaque.
Answer:

Question 5. Difference between Tooth associated and Epi- thelium-associated plaque.
Answer:

Question 6. Pellicle.
Answer:

Derived From:

• Components of saliva
• GCF
• Debris, bacterial, and host tissue cell products

Formed by: Selective adsorption of environment macromolecules

Functions:

• Acts as a protective barrier
• Lubricates surfaces to prevent tissue desiccation
• Provide substrate for bacterial attachment

Question 7. Socransky postulate.
Answer:

• It is for the identification of causative agents
• No. of etiologic organisms in the diseased site must be increased
• While it should be reduced in healthy sites
• If the etiologic organism is eliminated then disease pro-aggression ceases

Read And Learn More: Periodontics Question and Answers

• Presence of antibodies in organisms
• Presence of virulence factors
• In vitro, experiments should demonstrate the disease process

Question 8. Nonspecific Plaque Hypothesis.
Answer:

• It states that it is the total bulk of plaque that determines the pathogenicity rather than the individual species in it
• According to it. If a small amount of plaque is present then the products released by it can be neutralized by the host
• But if it is present in large quantity then it alters the host response
• It forms the basis of recent treatment and prevention modalities

Question 9. P. Gingivalis.
Answer:

• Porphyromonas gingivalis is a Gram-negative, anaerobic non-motile organism
• It is coccal to short rod shape
• It possesses fimbriae that facilitate adhesion and coag- aggregation

Virulence Factors:

Question 10. A.a. contains.
Answer:

• Actinobaillus actinomycetemcomitans is also known as aggregatibacter actinomycetemcomitans
• It is gram-negative, capnophilic,non-motile saccharolytic
• It occurs singly, in clumps, or in pair
• It is a small, short straight, or curved rod in shape

Virulence Factors:

Question 11. Name the stages of plaque formation.
Answer:

Stages Of Plaque Formation:

• Formation of pellicle on the tooth surface
• Initial adhesion and attachment of bacteria
• Colonization and plaque maturation

Question 12. Normal oral bacterial flora.
Answer:

• Normal bacterial flora associated with clinically healthy periodontium comprises of
  • Gram-positive cocci
  • Fusiform bacilli
  • Motile rods
  • Filaments
  • Spirochaetes

Question 13. Coaggregation.
Answer:

• In the process of plaque formation, the bacterial adherence to one another is termed coaggregation
• In the early stages of plaque formation there is coaggre It leads to food impaction nation between gram-negative and gram-positive organisms such as F. nucleatum and A. viscous followed by coaggregation in later stages between gram-negative organisms,  F.nucleatum, and P. gingivalis

Question 14. Spirochaetes.
Answer:

• Spirochaetes are corkscrew-like gram-negative anaerobic bacteria
• They are capable of immunosuppression
• They contain endotoxin that contributes to their path- Tends to accumulate on a gingival third of teeth genericity
• Treponema vincentii is responsible for necrotizing ulcerative gingivitis
• Increased levels of spirochetes occur in chronic and aggressive periodontitis
• Treponema pallidum is important in the pathogenesis of periodontal diseases
• A decrease in the levels of spirochaetes results in im- improvement in periodontal health

Question 15. Prevotella intermedia.
Answer:

• It is a Gram-negative, anaerobic organism
• It has short rods with rounded ends
• Possess fimbriae

Virulence Factors:

Question 16. Plunger Cusps.
Answer:

• Cusps that tend to forcibly wedge food interproximal are called plunger cusps
• It leads to food impaction
• Further results in gingivitis, periodontitis, tooth mobility, and pocket formation

Question 17. Materia alba.
Answer:

• Yellow/grayish-white, soft, sticky deposit, less adherent

Composition:

• Micro-organisms, desquamated epithelial cells, leukocytes, a mixture of salivary proteins and lipids
  They are capable of immunosuppression cytes, a mixture of salivary proteins and lipids
• Clearly visible, flushed away easily with water
• Tends to accumulate on the gingival third of teeth

Question 18. Bacterial Adherence/Formation.
Answer:

1. Via Electrostatic Interactions:

Negatively charged bacteria 11 calcium
↓↑
Negatively charged pellicle

2. Via Hydrophobic Interactions:

• Based on the fit of molecules of pellicle and plaque
• Lipoteichoic acid is responsible for this interaction by providing a long hydrophobic area

3. Via Lectin-like Substances:

• Lectin recognizes specific carbohydrates in the pellicle and becomes linked to it.

Question 19. Plaque Hypothesis.
Answer:

Non-Specific Plaque Hypothesis:

• States that the total bulk of plaque determines pathogenic- city rather than the species
• When only a small amount of plaque is present, it gets neutralized
• When a large amount of plaque is present, it causes disease

Specific Plaque Hypothesis:

• States that not all plaque is pathogenic and its path- genericity depends on the presence of certain specific pathogens in plaque
• Specific micro-organisms responsible for periodontal diseases release certain damaging factors
• This mediates the destruction of host tissue

Proof: Presence of A.a. contains in localized juvenile periodontitis

Question 20. Red complex
Answer:

• Secondary colonizers form red complex
  • It consists of
  • P. gingivalis
  • T. denticola
  • B. forsythias
• It is responsible for bleeding on probing