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Flashcards in Caries Microbiology 2 Deck (22)
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1

S. mutans transmission

¡Mother to infant

§Window of infectivity 6-18 months

§Caries found in all age groups

§

▪5-9 years   __% have caries

▪Teenage  __%

▪>18  __%

▪>75  ___% root caries

¡Mother to infant

§Window of infectivity 6-18 months

§Caries found in all age groups

§

▪5-9 years   50% have caries

▪Teenage  75%

▪>18  85%

▪>75  50% root caries

2

Lactobacilli and Caries

¡Lactobacilli have similar characteristics to Streptococci

____

___

________

¡Low numbers in ___ and ___ ____

¡High numbers in ___ ___ (why?_____)

  • Species: §Lactobacillus ____

¡Probably more involved in the progress of __ ___lesions

¡Lactobacilli have similar characteristics to Streptococci

§Aciduric

§Acidogenic

§Make EPS from sucrose

¡Low numbers in healthy sites, early caries (white spot lesions)

¡High numbers in dentinal caries (higher organic composition)

§Lactobacillus acidophilus

¡Probably more involved in the progress of deep enamel lesions

3

Gram Positive Lactobacilli

¡Lactobacilli

Species

  •  
  •  
  •  

§Produce ___ __

  • ▪Involved in __ ___

O2 ____ _____

§Small numbers on_____

§Higher numbers in _____

§High numbers in _____

¡Lactobacilli

§Lactobacillus  fermentum

§L. salivarius

§L. plantarum

§Produce lactic acid

▪Involved in yogurt production

§Facultative anaerobes

§Small numbers on healthy teeth

§Higher numbers in dentinal caries lesions

§High numbers in saliva of individuals with a high sugar diet

4

Root Caries

¡Gingival recession caused by aging/gum disease exposes tooth roots

___ ____ than coronal surface

____ and _____

___ ____

§Surface ____ adhere to ______ in pellicle

§Produce ____ acids in mature plaque (____)

§Produce less acid as the ____ _____

¡Gingival recession caused by aging/gum disease exposes tooth roots

¡Less mineralized than coronal surface

¡S. mutans and Lactobacilli

¡Actinomyces viscosus

§Surface fimbriae adhere to proline-rich proteins in pellicle

§Produce more acids in mature plaque (anaerobic)

§Produce less acid as the pH decreases

5

Actinomyces

¡Actinomyces

§A. ___

§A. ____

§A. ___

§A. ____

§Gram ___ ___ __

O2 ____ ____

§High numbers in plaque at ___ ___s and ___ ___

§High numbers in ___ caries

¡Actinomyces

§A. naeslundii

§A. odontolyticus

§A. viscosus

§A. israelii

§Gram positive branching rods

§Facultative anaerobes

§High numbers in plaque at approximal sites and gingival margin

§High numbers in root caries

6

Veillonella

___

O2 ____

¡Gram___ ___

____ as energy source

¡Symbiotic with ___ ___ ___

____ with Strep.

¡High numbers in ___sites

¡

¡Asaccharolytic

¡ Anaerobic

¡Gram negative cocci

¡Lactate as energy source

¡Symbiotic with glucose fermenting organisms

¡Co-aggregate with Strep.

¡High numbers in caries sites

¡

7

Veillonella – Strep Interactions

¡Veillonella stimulates ___ and ___ ___in S____ by __ ___.

¡Stimulates S. ____ growth in___ with other other Strep.

¡

¡Veillonella stimulates growth and IPS release in S. gordonii by quorum sensing

¡Stimulates S. mutans growth in competition with other other Strep.

¡

8

Cariogenic Bacteria Summary

______

  • ___ of ___ ___
  • ___ of ___ to ____
  • ___ ___ at ___ ___
  • ___ of ___
    • ____ acids in distinct regions of the biofilm
  • § production of ___
    • ▪converted to acid when_________

¡Behaviors

§transport fermentable sugars

§conversion of sugars to acid

§Sugar metabolism at low pH

§production of EPS

▪concentrate acids in distinct regions of the biofilm

§ production of IPS

▪converted to acid when free sugars are not available

§

§

9

Role of Saliva in Caries

  • ___ ___ __
    • §Longer retention times of food allows ___ ___ __ in ___
  • ___ ___ ___
    • §pH of saliva (____) counters the lactic acid produced by bacteria
    • §Provides ___ for _____n
  • ¡Head and Neck cancer Irradiation
    • §Saliva flow decreases to ___ ml/min
    • §___ caries
  • §
  • ¡

¡Removes food particles

§Longer retention times of food allows continuous pH reduction in plaque

¡Buffers acid production

§pH of saliva (6.8-7.2) counters the lactic acid produced by bacteria

§Provides minerals for re-mineralization

¡Head and Neck cancer Irradiation

§Saliva flow decreases to 0.02 ml/min

§Rampant caries

§

¡

10

Antimicrobial actions of saliva

__
___
___
___
___
___

 

echanical cleansing

Lysozyme

peroxidase

lactoferrin

leukocytes

secretory Iga

11

CAMBRA!

¡Caries risk assessment identifies those factors that are ____ and ___ ways an astute clinician can implement protective strategies that can ___ ___ and/or ___ ___ ___ to ___

___ ___ by ___ ___ (CAMBRA) focuses on treating and preventing the cause of the disease at an ___ ___, rather than waiting until it ___ ___ tothe ___ ___

¡ This article summarizes and simplifies information previously published about CAMBRA implementation from the perspective of today’s practicing clinician.

¡ The most recent science on prevention, ____ _____ and ___ as well as the use of ___ ___ and ___.

¡See more at: http://www.dentalaegis.com/cced/2009/03/clinical-assessment-a-clinician-s-guide-to-cambra-a-simple-approach#sthash.tjipdMZl.dpuf

¡Caries risk assessment identifies those factors that are pathologic and suggests ways an astute clinician can implement protective strategies that can prevent progression and/or return the patient to health.

¡Caries management by risk assessment (CAMBRA) focuses on treating and preventing the cause of the disease at an early stage, rather than waiting until it causes damage to tooth structure.

¡ This article summarizes and simplifies information previously published about CAMBRA implementation from the perspective of today’s practicing clinician.

¡ The most recent science on prevention, remineralization, antimicrobials, and pH, as well as the use of fluoride, xylitol, and casein phosphopeptide-amorphous calcium phosphate ( CCP-ACP) is also discussed.

¡See more at: http://www.dentalaegis.com/cced/2009/03/clinical-assessment-a-clinician-s-guide-to-cambra-a-simple-approach#sthash.tjipdMZl.dpuf

12

Caries Risk Test

___ ___ __ to ___ ___ ___

¡Take saliva sample,___

¡Add to ___ ___ ___

___ ___ hours to allow ___ ___

___ ___ samples

¡Chew paraffin wax to increase saliva flow

¡Take saliva sample, dilute

¡Add to CRT test strip

¡Incubate 48 hours to allow bacterial growth

¡Count bacteria in samples

13

S. mutans/Lactobacilli

  <______>

  low risk

  >_____

  high risk

S. mutans/Lactobacilli

  <100,000 CFU/ml

  low risk

  >100,000 CFU/ml

  high risk

14

Possible Indications for CRT

¡Before ___ or ___

___ with __ ___

¡Before ___

¡Not indicated if cavities or initial lesions present

¡Before restorations, or crowns

¡Mothers with small children

¡Before orthodontic treatment

¡Not indicated if cavities or initial lesions present

15

Methods of Caries Control

  • ¡Surgical
    • §Treats __ ___ but not___
  • ¡Non-surgical
    • ___/___ modification
    • ____
    • ____ agents
      • ___
      • ___
    • _____ agents
      • ___
      • ___
    • ___ ____ (_____)
    • §Caries____

¡Surgical

§Treats clinical signs but not microbiology

¡Non-surgical

§Diet/behavioral modification

§Sealants

§Anticariogenic agents

▪Fluoride

▪Xylitol

§Chemotheraputic agents

▪Chlorhexidine

▪Triclosan

§Replacement strains (pro-biotics)

§Caries vaccine

§

§

16

 Methods of Preventing Caries

increase ____

decrease ____

Reduce or eliminate ___ ___

Increase tooth resistance to acid attack

Decrease tooth suseptibility

Reduce or eliminate cariogenic microbes

17

Fluoride Therapy

¡Fluoride has a ____effect on the ______n of enamel, fluorapatite is ___ ___ in acid

¡Enhances crystal structure of hydroxyapatite by ___ ____

¡Antibacterial properties

  • __ __ ___
  • ___ ___
  • ___ ____

¡Fluoride has a inhibitory effect on the demineralization of enamel, fluorapatite is less soluble in acid

¡Enhances crystal structure of hydroxyapatite by catalyzing remineralization

¡Antibacterial properties

§Bacterial membrane permeability

§Reduces glycolysis (less acid production)

§Inhibits synthesis of IPS

18

Anticaries Activities of Fluoride

  1. Systemic
  2. Topical
  3. Antimicrobial

19

Xylitol:

¡Natural __ ___

§Similar ___ to ___

____ to produce

§Xylitol in ___ ____

¡Not ___ by most oral bacteria

¡Reduced incidence of ___ in children with regular exposure

¡Adults using xylitol chewing gum less likely to__ to ___

¡

20

¡Decreases bacterial ___

§Very few oral species can ___

§Less__ ___ __

¡Reduced production of __ ___

¡Reduces number of ___ in __ and ___

____ cycle

¡• Stimulates __ ___

¡Decreases bacterial metabolism

§Very few oral species can use

§Less lactic acid produced

¡Reduced production of biofilm matrix.

¡Reduces number of S. mutans in plaque and saliva

§Futile cycle

¡• Stimulates salivary secretion

21

Probiotics and Strain Replacement

___ ___: ____

___ ___ ___  ____. -strain replacement

¡

¡

¡Lactobacillus reuteri- probiotic

¡Genetically altered Streptococcal spp. -strain replacement

¡

¡

22

Caries Vaccine

¡Whole S. mutans vaccine

__________________

¡Targeted antigen vaccines

____ is main salivary antibody

__ __ response

§Must be ___ ____ for long term response

¡Whole S. mutans vaccine

§Antibodies to Serotypes a b c d cross react with human heart tissues

¡Targeted antigen vaccines

§sIgA is main salivary antibody

§Short term response

§Must be boosted repeatedly for long term response