Card Set Information
When is bacterial infection irreversible?
Once it hits the pulp
How do bacteria invade the pulp?
Bacteria advance through the
What are some portals of entry for bacteria to the pulp?
where are the microbes located in endodontic infections?
necrotic pulp tissue (major site)
What is the etiologic agent of pulpal infection and periradicular lesion formation?
What caused necrosis of the pulp?
The severance of blood supply (no metabolic activity)
What do all teeth with periapical osteitis have?
They all harbor bacteria.
No bacteria were isolated from teeth without it
Most samples had
more than one bacterial strain
which bacteria are prevalent in pulpal infection?
Obligate anaerobic bacteria
Fusobacterium, Bacteroides, Peptococcus, Peptostreptococcus
When does a periapical immune response occur?
infection overwhelms pulpal defenses
and destroys the pulp tissue
The periapical respnse is the second line of defense
What causes a periapical lesion?
The accumulation of inflammatory cells and bone destruction
Which bacteria are associated with caries? Deep caries?
mostly strict anaerobes
What did the necrotic dental pulp study of 1976 show?
1. Most samples had more than one bacterial strain
2. Predominance of
obligate anaerobic bacteria
fusobacterium, bacteroides, eubacterium, peptostreptococcus
What is the root canal flora of
but necrotic teeth with a diseased apex?
It is dominated (90%+) by
fusobacterium, porphyromonas, prevotella, eubacterium
What is the microbial composition of
with necrotic pulp and diseased periapex?
It is less dominated (<70%) by
What are some species of polymicrobial endodontic infections?
black-pigmented (denticolla, intermedia, nigrescenst)
Can fungi be present at the foramen of a root canal with a periapical granuloma?
Possible nutritional relationships between bacteria inthe root canal
What is the active component of Lipopolysaccharide (LPS) implicated in bacterial virulence?
is the active component. It also has an O-specific chain
How can you maximize endodontic prognosis?
By eliminating the microorganisms from infected root canals
What is the core concept of endodontic treatment?
followed by an
of the root canal system
How do we treat vital pulp?
How do we treat necrotic pulp?
We treat by disrupting the
microbial ecosystem by bacterial removal
, as well as their byproducts and substate, from the canal system
What do you do for emergency treatment of necrotic pulp?
of pulp space
of canal or soft tissue
What do you do during an average endo treatment?
1. endo access
2. Determine working length
3. disinfect root canal
4. intracanal medication
5. place root filling
7. observation and follow up
Tooth and rubber dam disinfection materials
1. 30% H202
2. 5% iodine tincture or .5% CHX
3. 6% Sodium Hypochlorite
Root canal irrigants/disinfectants
Removal of smear layer compounds
Irrigate with distilled water, then..
Citric Acid, EDTA, MTAD
What do you use to medicate between appointments? What does it do?
Hydrolyzes lipid moiety of bacterial LPS, alters properties
What usually happens to periapical lesions after treatment is complete?
The lesions absolve through
repair and regeneration
Which has a higher success rate after RCT, + or - cultures?
- cultures (88.6%) have more than + (75%)
What complicates the success of root canal therapies?
The presence of bacteria can greatly affect the sucess
The micro flora of failed RCT is different from untreated teeth
What is the most commonly recovered bacteria in failed root canals?
Which factors of microbes have a negative impact on prognosis of treatment?
Infection at time of root filing
Size of preperative periapical lesion
Which medical condition reduces the success of endo treatment?