Lecture 2 (8/29) Flashcards
Provides an ideal environment for bacterial colonization:
root canal system
Why is the RC system an ideal environment for bacterial colonization?
- warm
- moist
- nutritious (has lots of substrate)
Describe the climate of the RC system:
variable but largely anaerobic climate
What allows the RC system to be largely protected from the host defenses?
due to lack of circulation in a diseased pulp
What does the lack of circulation in a diseased pulp allow for?
The area to be protected from the host defenses
Because the root canal system of a diseased pulp does not have circulation allowing it to evade host defenses, it is considered a:
privileged sanctuary
The basic science most closely associated with the practice of endodontics:
microbiology
By using a special “anaerobic glove box: technique, ____ were successfully cultured from the canal system
anaerobic bacteria
Sundqvist proved that many of the pathological bacteria found in the root canal system are:
black pigmented anaerobic gram negative rods
The black pigmented anaerobic gram negative rods found in the RC system: (6)
- porphyromonas
- prevotella nigrescens
- peptostreptococcus
- fusobacterium
- eubacterium
- actinomyces
Black pigmented anaerobic rods found in the RC system release:
Lipopolysaccharides (LPS), also known as endotoxins: fever, collagenolysis, osteolysis
The LPS (also known as endotoxins) released by the black pigmented anaerobic rods can cause:
- fever
- collagenolysis
- osteolysis
The root canal walls/spaces are conductive for the formation of:
biofilm
A complex, colonized community of bacteria:
biofilm
In an infection, ____ is adhered to the root canal walls
biofilm
“floating bacteria”
planktonic
Ricucci states that with apical periodontitis, :
NO single microorganism is responsible
Progression of RC system infections:
- carious lesion or trauma opens tubules to _____.
- Bacteria inflame the ___.
- ___ may overcome the pulpal defenses and ____ may form in the ____.
- Infection increases in the pulp and ___ begins
- ____ involves the entire ___
- Infection uses “portals of exit” (_______) to invade _____ (_____)
- ____ infection occurs beyond ___ (_____)
- bacterial invasion
- pulp locally
- Inflammation; localized abscesses; coronal pulp
- necrosis
- necrosis; entire root canal system
- apical foramen & lateral canals; periradicular tissues (apical periodontitis)
- periradicular; apex (apical abscess)
During the progression of RC system infections:
What opens the tubules to bacterial invasion?
carious lesion or trauma
During the progression of RC system infections:
What is the significance of a carious lesion or trauma?
opens tubules to bacterial invasion
During the progression of RC system infections:
Initially, where does the inflammation from the bacteria occur?
locally within the pulp
During the progression of RC system infections:
What happens when inflammation overcomes the pulpal defenses?
localized abscesses may form in coronal pulp
During the progression of RC system infections:
Localized abscesses may form in the coronal pulp once what occurs?
once inflammation overcomes the pulpal defenses
During the progression of RC system infections:
Once infection increases in the pulp, what may begin?
necrosis
During the progression of RC system infections:
Necrosis involves:
the entire RC system
During the progression of RC system infections:
What are the “portals of exit” used by the infection to invade peri-radicular tissues?
apical foramen and lateral canals
During the progression of RC system infections:
Once infection invades the peri-radicular tissues this is considered:
apical periodontitis
During the progression of RC system infections:
Where does periradicular infection occur?
beyond the apex
During the progression of RC system infections:
When a periradicular infection occurs beyond the apex:
apical abscess
The biofilm must accomplish 6 things to cause:
disease within the RC system
What 6 things must a biofilm accomplish in order to cause disease with RC system?
- MO must adhere to host surfaces
- Obtain nutrients from the host
- Multiply
- Invade tissue
- Overcome host defenses
- Introduce tissue damage
How could we describe a biofilm?
- complex
- variable
- constantly changing
A multicellular microbial community characterized by cells that are firmly attached to a surface and enmeshed in a self produced matrix of extracellular polymeric substance (EPS), usually polysaccharide:
biofilm
Biofilms are usually enmeshed in a self produced matrix of:
Extracellular polymeric substance (EPS) usually polysaccharide
Bacteria that appear to be the most common microorganisms in primary endodontic infections:
anaerobic gram negative
List the most common anaerobic gram negative microorganisms in primary endodontic infections: (7)
- porphyromonas
- prevotella
- propionibacterium
- peptostreptococcus
- streptococcus
- actinomyces
- olsenella
porphyromonas
prevotella
propionibacterium
peptostreptococcus
actinomyces
olsenella
What do all of these microorganisms have in common?
anaerobic gram negative
The long the infection exists in the RC system, the more ___ is consumed by bacterial activity and the more ___ the RC system environment becomes
oxygen; anaerobic
The longer the infection exists within the RC system, the more oxygen is consumed by bacterial activity and the more anaerobic the RC environment becomes
Therefore ___ infections within the RC system tend to favor ___ bacterial flora
chronic infections; anaerobic
Explains why chronic infections within the RC system tend to favor anaerobic bacterial flora:
because the longer the infection exists within the RC, the more the bacteria consume the oxygen leaving the RC environment to be more anaerobic
What type of bacteria do chronic infections in the RC system favor??
anaerobic bacterial flora
As a rule ____ is responsible for an Endo infection
No ONE organism
All endo infections are ___ (___)
mixed; polymicrobial
Endo infections are mostly caused by ___ & ____ ___
facultative and obligate anaerobes
Aerobes which can also survive in an an anaerobic environment:
facultative anaerobes
Facultative anaerobes may become more numerous & virulent with:
the addition of oxygen
Bacterial species that must anaerobic environment to survive:
obligate anaerobe
Bacterial species that cannot survive in aerobic environments:
obligate anaerobe
_____ liberates O2
NaOCl
Biofilm becomes more varied, complex, and difficult to control when the tooth is further challenged by ____ or ____ (_____ or _____)
salivary contact or operative contamination (new bugs or altered environment)
_____ becomes more varied, complex, and difficult to control when the tooth is further challenged by salivary contact or operative contamination (New BUGS or altered environment)
Biofilm
Biofilm becomes more varied, complex, and difficult to control when the tooth is further challenged by salivary contact or operative contamination (New BUGS or altered environment)
SO _____ of rubber dam or temporary AND _____ during treatment (leaky dental dam, etc.)
avoid leakage; avoid iatrogenic contamination
How do we destroy the bacteria in RC treatment?
8.3% sodium hypochlorite (NaOCl)
Our major weapons in destroying RC bacteria:
cleaning and shaping with NaOCl and intra-canal medicaments
How does the NaOCl work to kill the RC bacteria?
kills directly or starves them out
What makes RCs resistant to mechanical shaping?
diverse shapes are resistant to mechanical shaping
(Files never reach ALL spaces in the complex pulpal system)
What implication does the diverse shape of RCs have on mechanical shaping?
Files never reach ALL spaces in the complex pulpal system
Due to diverse shapes of RC systems, files never reach ALL spaces in the complex pulpal system, therefore correct use of ___ is extremely important and ____.
NaOCl; eliminating microorganisms in these spaces
What are the 6 functions of NaOCl?
- disinfect over time
- dilutes an inactivates toxins
- dissolves substrate over time
- dissolves necrotic tissue over time
- flushes & floats out debris
- lubricates canals
Typical RC treatment case requires about ____ of ____ as irrigant PER VISIT.
10-12 cc. of NaOCl
____ degrades rapidly to ____ (salt water) in the canal, therefore must be replenished @3-5 min
NaOCl; NaCl
NaOCl degrades rapidly to NaCl (salt water) in the canal, therefore must be:
replenished @ 3-5 min
NaOCl must be in contact with shaped canal a minimum of ____ after the canal enlarged to ____ or larger
30 minutes; #30
During RC treatment, why must the canal be enlarged to #30 or greater?
a canal smaller than #30 will seldom if ever allow any irrigant to reach the apical 1/3 of the canal
Enlarging the canal to #30 or larger allows for:
irrigant to reach the apical 1/3 of the canal
Medications are placed ____ the canal system ___ appointments
within; between
The medications that are placed within the canal system between appointments are intended to increase ___ and to further decrease ____ within the RC system
local antimicrobial action; decrease the microbial challenge
Historically, many harsh medications were used in RC treatment were ___ & ___ to healthy tissue
toxic; damaging
Some of the medications that were historically used to RC treatment are now recognized as ___ and are no longer acceptable for use
carcinogenic
Due to their toxic/and or carcinogenic nature, the following formulations are no longer acceptable for use in RC treatment (4):
- CMCP
- Formocresol
- Cresatin
- Beachwood Creosote
Near universal acceptance as the intracranial medication of choice (esp. in necrotic cases)
CaOH
The pH of the intracranial medication CaOH:
between 11 & 12
CaOH discourages ____ microbial growth
MOST
What four characteristics of CaOH make it a widely accepted intracanal medication?
- discourages MOST microbial growth
- long-lasting (effective over extended periods of time)
- no reported allergic responses
- easy to apply & remove as a paste
What is CaOH available in clinic as?
Ultracal
Use of antibiotics to relieve pain:
useless
Systemic antibiotics are ONLY useful in: (2)
- acute P-R infections (swelling & fever)
- immunologically surpassed patient
What type of infection would present as swelling & fever and may require use of antibiotic treatment?
Acute P-R infections
Healthy patients WITHOUT systemic signs & symptoms of infections but WITH the following conditions do NOT require antibiotics (4):
- symptomatic pulpitis
- symptomatic apical periodontitis
- a draining sinus tract
- localized swelling
healthy patients that present with symptomatic pulpits, symptomatic apical periodontitis, a draining sinus tract, or localized swelling, that otherwise are healthy without systemic signs and symptoms of infection do NOT requires:
Treatment with antibiotics
What indicates performance of an I&D?
usually fluctuant swelling
Drainage fluctuant swelling is accomplished by:
I&D (incision & drainage)
Following treatment of I&D we are committed to:
following the acute patient daily & monitoring progress
When do we use antibiotics in endodontics?
In conjunction with definitive procedures to deride and drain when there is:
- persistent or spreading infection
- systemic involvement with temp of 100+
- medically compromised patient
- pre-med when indicated
If bacteria from the infected pulp tissue gain entry into the periradicular tissue and the immune system is unable to suppress the invasion, and otherwise healthy patient eventually shows signs and symptoms of an _____, _____ or both.
acute periradicular abscess; cellulitis
If bacteria from the infected pulp tissue gain entry into the periradicular tissue and the immune system is unable to suppress the invasion, and otherwise healthy patient eventually shows signs and symptoms of an acute periradicular abscess, cellulitis, or both.
Clinically this patient experiences:
swelling, fever, and mild to severe pain
A patient may develop acute periradicular abscess, cellulitis, or both If the bacteria from the infected pulp tissue gains entry into the ___ and the ___ is unable to suppress the invasion
periradicular tissue; immune system
Depending on the relationship of the apices of the involved tooth to the muscular attachments, virulence factors and host resistance, the swelling may be ____ or may extending into a ___
localized to the vestibule; fascial space (cellulitis)
When swelling extends into a fascial space:
cellulitis
What factors may determine whether swelling will remain localized to the vestibule or whether it will extend into the fascial space resulting in cellulitis?
- relationship of apices of involved tooth muscular attachments
- virulence factors
- host resistance
A patient presenting with cellulitis generally will also have ___ such as ___.
systemic manifestations:
- fever
- chills
- lymphadenopathy
- headache
- nausea
In cases off cellulitis with systemic manifestations, because the reaction to the infection may occur very quickly, the involved tooth may or may not show radiographic evidence of:
A widened periodontal ligament space
In cases of cellulitis with systemic manifestations, because the reaction to the infection may occur very quickly, the involved tooth may or may not show radiographic evidence of a widened periodontal ligament space.
However in most cases, the tooth elicits a positive response to ___, and the periradicular area is ___.
positive response to percussion; tender to palpation
In cases of cellulitis with systemic manifestations, because the reaction to the infection may occur very quickly, the involved tooth may or may not show radiographic evidence of a widened periodontal ligament space.
However in most cases, the tooth elicits a positive response to percussion, and the periradicular area is tender to palpation
Describe this case:
This is a serious (critical infection) in fascial plane
_____ are important in relation to where the lesion “points”
muscle attachments
If lesion exits coronal muscle to attachment, it is generally on ___ or ___ and we have a localized abscess (which is more easily treated due to no systemic involvement)
attached gingival or alveolar mucosa
If lesion exits coronal muscle attachment, it is generally on attached gingiva or alveolar mucosa and we have a:
localized abscess
___ is more easily treated because no systemic involvement
localized abscess
The following image would be diagnosed as
localized abscess
What could be diagnosed looking a the following patient?
Fluctuant swelling; I&D
____ are the potential anatomic areas that exist between the fascia and underlying organs and other tissues:
fascial spaces
Development of a critical infection:
During an infection, fascial spaces are formed as a result of:
spread of purulent exudate
The spread of infection of odontogenic origin into the fascial spaces of the head and neck is determined by the ____ of ____ of the involved tooth in relation to its overlying ____ or ___ and the relationship of the apex to the ____.
location of the root end; buccal or lingual cortical plate; attachment of muscle
The spread of infection of _____ origin into the fascial spaces of the head and neck is determined by the location of the root end of the involved tooth in relation to its overlying buccal or lingual cortisol plate and the relationship of the apex to the attachment of muscle.
odontogenic
The spread of infection of odontogienic origin into the fascial spaces of the head and neck is determined by the location of the root end of the involved tooth in relation to its overlying buccal or lingual cortisol plate and the relationship of the:
apex to the attachment of muscle
If the source of the infection is a mandibular molar and the apices of the molar lie closer to the lingual cortical plate and above the attachment of mylohyoid muscle of the floor of the mouth, the purulent exudate breaks through the cortical plate into the _____.
If the apices yes below (or apical) to tea attachment of the mylohyoid muscle, the infection spreads into the ____.
sublingual space; submandibular space
Infections that spread into the fascial spaces are critical and have the potential to be ____ if not ___
lethal; treated aggressively
Label the following image:
A: Submandibular space
We should be especially vigilant with infections of ____ (especially _____) when cellulitis occurs in the submandibular space with swallowing difficulty
mandibular molars; 2nd and 3rd molars
We should be especially vigilant with infection of mandibular molars (especially 2nd and 3rd molars) when:
cellulitis occurs in the submandibular space with swallowing difficulty
We are especially vigilant with infections of mandibular molars when cellulitis occurs in submandibular space with swallowing difficulty, why?
Access from S-M space to sublingual and submittal spaces (all 3 are called Ludwig’s Angina) and infection in these spaces can be life threatening
What can you diagnose looking at the following image?
Cellulitis with involvement of the submandibular space
This is cellulitis with involvement of the submandibular space. The infection has pointed apical to the attachment of the ___ muscle and superior to the ____ muscle.
What treatment is indicated?
mylohyoid muscle; platysma muscle
I&D; Referral
Endodontic infections may be classified according to:
- location
- symptoms (acute or chronic)
- degree of virulence or organization (localized or diffuse and spreading)
How might you describe the symptoms of an endodontic infection?
acute or chronic
How might you describe the degree of virulence or organization of and endodontic infection?
localized or diffuse and spreading
How might you classify the location of an endodontic infection?
- intraradicular
- extraradicular
Location of endodontic infection that is caused by bugs colonizing within the RCS:
Intraradicular
Location of endodontic infection that is usually a sequel to untreated intradicular infection:
extraradicular
Location of endodontic infection that is characterized by microbial invasion of the periradicular tissues resulting in inflammation and infection. AAA or CAA
extraradicular
Intraradicular infection is caused by bugs colonizing within the ____. Extraradicular infection is caused by microbial invasion of the _____ tissues.
RCS; periradicular tissues
What are the 3 subclasses of intraradicular infections?
- primary infections
- secondary infection
- persistant infection
Intraradicular infection caused by the bugs that initially invade and colonize necrotic pulp tissues within the RCS:
Primary infection
Intraradicular infection caused by bugs not present in the primary infection but introduced into the RCS sometime following professional intervention (secondary to professional intervention; iatrogenic by definition)
Secondary infection
Secondary intraradicular infections are secondary to professional intervention meaning they are:
iatrogenic by definition
Example of a ____ infection is when symptoms arise in a previously ASYMPTOMATIC infected tooth if operator allowed R. Dam leakage or placed leaky temporary.
secondary infection
Example of a secondary infection is when symptoms arise in a previously ______ infected tooth if operator allowed R. Dam leakage or placed leaky temporary.
asymptomatic
intraradicular infection caused by bugs that were members of a primary or secondary infection and in some way, resisted intracanal antimicrobial procedures and were able to endure periods of nutrient deprivation within the RCS (i.e.) FAILURE OF RCT TO HEAL
persistant infection
How can we describe an intraradicular persistent infection?
FAILURE of RCT TO HEAL
The ability to form ____ has been regarded as a virulence factor
BIO
The ability to form BIO has been regarded as a virulence factor. Neighboring cells of different species can produce enzymes such as ____, ____ and _____ that are retained in the biofilm matrix and can protect other bacteria against antibiotics and host defenses.
B-Lactamase, Catalase, proteinases
In an endodontic infection, bacterial products contribute to:
virulence
_____ can cause direct tissue damage & osseous breakdown by releasing enzymes, endotoxins, LPS & peptides/amino acids
gram negative anaerobes
gram negative anaerobes can cause ____ & ____ by releasing enzymes, endotoxins/exotoxins, LPS & peptides/amino acids
direct tissue damage & osseous breakdown
gram negative anaerobes can cause direct tissue damage & osseous breakdown by releasing:
- enzymes
- endotoxins/exotoxins
- LPS
- peptides/amino acids
What are some enzymes that are released by gram negative anaerobes that can cause direct tissue damage & osseous breakdown?
- collagenase
- chondroitinase
- hyaluronidase
Toxic substances associated with the outer cell walls that are released upon destruction of cell walls and exotoxins:
endotoxins
An endotoxin in the cell wall of gram negative bugs:
LPS
Bacteria responsible for causing serious suppurative infections:
Staph Aureus (S. Pyogenes)
Is staph aureus (S. pyogenes) gram negative or gram positive?
gram positive
What is the oxygen requirement for S. Aureus (S. Pyogenes)?
facultative anaerobe
Staph Aureus (AKA) S. Pyogenes (Gram +) is thought to produce:
penicillinase
A B-lactamase that has the potential to render PCN ineffective:
Penicillinase
What bacteria is thought to be responsible for the production of penicillinase:
S. Aureus (S. Pyogenes)
Staph Aureus (S. Pyogenes) treatment:
Augmentin
Augment is the combination of:
Amoxicillin + Clavulanic acid
Clavulanic acid inhibits:
penicillinase
