Microbiology

Question 1

Bacteria is a major etiological factor factor in the progression of pulpal inflammation to apical periodontitis. (germ-free rats).

Answer 1

Kakehashi et al

Question 2

Bacteria present in necrotic pulps with apical periodontitis but not in necrotic pulps without apical disease.

Answer 2

Sundqvist

Question 3

Focal infection theory in endodontics – bacteria trapped in dentinal tubules could leak and cause systemic disease.

Answer 3

Weston Price 1925

Question 4

Refuted the focal infection theory in endodontics.

Answer 4

Easlick 1952

Question 5

A basis for the success of RCT

Answer 5

“The Zones of Fish” – If the nidus of infection is removed, then the body can recover.

Question 6

Gram-positive Bacteria

Answer 6

Streptococcus, enterococcus, lactobacillus, actinomyces. Thick petidoglycan cell walls. Stain crystal violet.

Question 7

Gram-negative Bacteria

Answer 7

Fusobacterium, treponema, porphyromonas, tannarella, campylobacter. Cell walls contain LPS. Less affinity for crystal violet.

Question 8

_______ is important in progression of pulpal and periapical inflammation – stimulate cytokine production in macrophages.

Answer 8

LPS
Torabinejad and Dwyer

Question 9

________ caused by trauma allow bacterial ingress.

Answer 9

Microcracks
Bergenholtz

Question 10

Anachoresis – homing of bacteria to traumatized, unexposed pulps proposed by ______

Answer 10

Gier and Mitchell

Question 11

Disproved anachoresis

Answer 11

Delivanis et al

Question 12

Endodontic infections require _____ and are ______ in nature

Answer 12

Disruption of protective barrier
Polymicrobial

Question 13

A microbial derived, sessile community characterized by cells irreversibly attached to a substratum, or interface, or to one another, embedded in a self-produced matrix of extracellular polymeric substances, and exhibiting an altered phenotype with respect to growth rate and gene transcription compared to planktonic counterparts.

Answer 13

Biofilm defined by Donlan and Costerton

Question 14

Svensater and Bergenholtz qualities unique to biofilms. (4)

Answer 14

Metabolic diversity
Concentration gradient
genetic exchange
quorum sensiing

Question 15

Abscesses are not sterile, supports the validity of _________.

Answer 15

Extraradicular infections

Tronstad – anaerobes present in extraradicular infections
Sunde – molecular techniques (Agreggatibacter, actino, tanerella)

Question 16

________ present in sinus tracts

Answer 16

Bacteria
Haapasalo

Question 17

Cytomegalovirus and EBV in AP

Answer 17

Sabeti

Question 18

More _____ and ______ when parulis present

Answer 18

Fusobacterium
P ging
Sassone

Question 19

______ can occur despite pulpal necrosis in luxated teeth without contamination.

Answer 19

Healing
Andreasen

Question 20

_____% of necrotic teeth are infected

Answer 20

64%
Wittgow and Sabiston

Question 21

Typically isolated species types (oxygen need)

Answer 21

Facultative and obligate anaerobes

Question 22

Typically isolated species

Answer 22

Strep, enterrococcus, porphyromonas, prevotella

Question 23

Infection profiles vary _______

Answer 23

Geographically
Baumgartner

Question 24

________ strep more common in endo infections

Answer 24

Beta-hemolytic
Winkler and Van Amerongen

Question 25

E faecalis is of particular interest due to

Answer 25

Antimicrobial resistance

Question 26

E Faecalis unique properties (3)

Answer 26

Proton pump -- Evans Survives in dentinal tubules -- Love Can form bioflims -- Distel

Question 27

E Faecalis proton pump provides resistance to

Answer 27

CaOH. Prevents the ionization that is required for it mechanism of action. Bystrom.

Question 28

"Black Pigmented Bacteroides" split into (use of sugar)

Answer 28

Prevotella (sacchrolytic) Porphyromonas (asacchrolytic)

Question 29

Atypical species in endodontic infections (4)

Answer 29

Actinomyces Spirochetes Fungi Arachaea

Question 30

Actinomyces is associated with _____ and are common cause of ______

Answer 30

Sulfur granules -- Sunde persistent endodontic infections (survives and thrives in periapical area) -- Nair

Question 31

Spirochetes have ____

Answer 31

flagella for motility. Treponema detected by Siqueira.

Question 32

Archaea present in pulp

Answer 32

Vianna

Question 33

Candida present in primary endodontic infections

Answer 33

Baumgartner

Question 34

________ have not been detected in dental pulp

Answer 34

Prions Azarpazhooh and Fillery

Question 35

HSV 1 and 2, HHV, VZV present in acute apical abscesses

Answer 35

Ferreira

Question 36

Viruses may play an active role in pulpal death

Answer 36

Goon and Jacobsen. Devitalization of pulps associated with trigeminal VZV infection.

Question 37

Association between feline herpesvirus and invasive cervical root resorption.

Answer 37

Von arx

Question 38

HPV in endodontic abscesses

Answer 38

Ferreira

Question 39

_______ in pulps of patients with clinical AIDS

Answer 39

HIV Glick

Question 40

______ in periapical lesions of HIV+ patients

Answer 40

HIV Elkins

Question 41

Greater number of bacterial species present in

Answer 41

Primary infections 20 in primary vs 3 in secondary Rocas and Siqueria

Question 42

Primary infection composition

Answer 42

Equal mix of gram-positive and gram-negative. Mostly obligate anaerobes. Sundqvist

Question 43

Secondary infection composition

Answer 43

Mostly gram-positive. More equal distribution of facultative and obligate anaerobes. Sundqvist

Question 44

Progression of primary infections from aerobic and anaerobic species as oxygen tension decreases.

Answer 44

Microbial Succession. Fabricius

Question 45

_________ frequently associated with secondary infections.

Answer 45

E faecalis Siqueira

Question 46

________ with symptomatic infections

Answer 46

Fusobacterium — Siqueira T forsythia — Sassone

Question 47

T forsythia with painful infections

Answer 47

Sassone

Question 48

EBV and CMV with painful infections

Answer 48

Sabeti

Question 49

Buccal Vestibule

Answer 49

Defined by buccinators and the alveolar mucosa. Mx posterior apices inferior to insertion and Mn posterior apices superior to insertion will spread to this space.

Question 50

Buccal Space

Answer 50

Defined by buccinators and cheek mucosa. Mx posterior apices superior to insertion and Mn posterior apices inferior to insertion will spread to this space. Can spread to periorbital space.

Question 51

Pterygomandibular Space

Answer 51

Defined by the medial pterygoid and the mandibular ramus inferior to the lateral pterygoid. Mn second and third molar infections can spread here.

Question 52

Canine Space

Answer 52

Superior to the levator anguli oris muscle and inferior to the levator labii superioris. Mx canines and first premolar infections disrupting the buccal cortex can spread to this space.

Question 53

Periorbital Space

Answer 53

Deep to the orbicularis occuli. Infections from Mx canines and large buccal space infections can spread to this space.

Question 54

Submandibular Space

Answer 54

Superior to the platysma and inferior to the mylohyoid muscle. Mn posterior infections disrupting the lingual cortex can spread to this space. Continuous with the submental space across the digastric muscle.

Question 55

Submental Space

Answer 55

Superior to the platysma and inferior to the mylohyoid muscle. Mn anterior infections can spread here.

Question 56

Mental Space

Answer 56

Below the mentalis muscle. Mn anterior infections can spread here.

Question 57

Sublingual Space

Answer 57

Superior to the mylohyoid and inferior to the floor of the mouth. Mn infections that disrupt the lingual cortex can spread here. This space is bilateral without midline separation.

Question 58

Lateral pharyngeal space infection

Answer 58

Mn second or third molar infection spreads beyond to pterygomandibular space. Can cause inner jugular thrombosis.

Question 59

Ludwig angina

Answer 59

Combination of submental, sublingual, and submandibular space infections

Question 60

Cavernous sinus thrombosis

Answer 60

Periorbital space infection spreads via valveless facial veins.

Question 61

Danger space

Answer 61

Alar and pre-vertebral fascia. Continuous with mediastinum. Infections that spread beyond the lateral pharyngeal space.