Pulpal, Periapical, Odontogenic, and Bone Infecitons

Question 1

What makes the pulp a unique organ?

Answer 1

It is enclosed in hard tissue and inflammation can be particularly damaging

Question 2

Why can pulpal inflammation be so damaging?

Answer 2

Increased interpulpal pressure can occur because it is surrounded by hard tissue and can’t go anywhere
This compromises blood flow, resulting in tissue damage
Irreversible damage leads to pulpal necrosis

Question 3

What makes the tooth so unique (for the purpose of this lecture)?

Answer 3

Roots are enclosed in bone, and the ingress for circulation is tiny and also surrounded by bone

Question 4

What is the most common cause of pulpal inflammation and necrosis?

Answer 4

Bacterial infection

Question 5

How can bacteria infect the pulp?

Answer 5

Direct pulp exposure
Bacterial penetration through dentinal tubules from caries
Direct access due to traumatic fracture of the tooth
Travel from bloodstream (unlikely)

Question 6

Traumatic fracture can lead to what?

Answer 6

Bacteria can easily enter the pulp
Infection happens quickly if pulps are not mechanically sealed
trauma may damage the blood supply or sever the apex resulting in tissue death

Question 7

What occurs is the pulp is non-vital?

Answer 7

There is a disruption of positive fluid flow, making the tooth more vulnerable to invasion by microbes
Infection may take a long time depending on bacterial access
There’s no immune response so bacteria can easily grow once they arrive

Question 8

T/F - Bacteria are necessary for pulpal and periapical disease to occure

Answer 8

True - that’s why a good seal is critical for the success of pulpal therapy

Question 9

What characteristics do bacterial species involved with pulpal and periapical disease have?

Answer 9

Anaerobic
gram-
bacilli
Multiple species are found in infecitons

Question 10

T/F - DNA-based studies show different bacterial profiles of infections than those seen in previous cultivaiton-based studies

Answer 10

True

Question 11

What are the most common species of periapical infection based on DNA analysis?

Answer 11

Enterococcus faecalis
Burkolderia
Streptococcus

Question 12

What species are the most common based on cultivation studies with periapical abscesses?

Answer 12

Prevotella and Porphyomonas

They’re responsible for the foul odor of necrotic pulps

Question 13

T/F - endodontic infections usually only have one species

Answer 13

False - they’re mixed bacterial infections

Question 14

How does oxygen concentration vary in the canal of a pulpal infection?

Answer 14

There’s a gradient depending on the area of necrosis

Necrotic canals have anaerobic conditions

Question 15

How do nutrients differ in the canal of pulpal infections?

Answer 15

Coronally = salivary constituents and ingested food (saccrolytic bacteria found here)
More apically = serum and cellular proteins are more avaliable (proteolytic bacteria found here)

Question 16

Pulpitis

Answer 16

Early stage of endodontic infeciton
Pulp is compromised by infection
Can be reversed if treated early
Early symptoms include lowered threshold and prolonged pain response to cold or other stimulus

Question 17

What is the sign of the shift from reversible to irreversible pulpitis and eventually pulpal necrosis?

Answer 17

Spontaneous pain signals

-pain can be quite severe (sharp or throbbing)

Question 18

As pulp becomes necrotic, what happens to immune cells?

Answer 18

They can’t enter the pulp due to a lack of blood supply, so the response shifts to the periapical region

Question 19

What happens as immune response shifts to periapical tissues?

Answer 19

Bone resorption takes place and allows space for a barrier of inflammatory cells to accumulate and prevent spread of infection
Inflammatory response is usually effective and bacteria are confined to periapical tissues (otherwise, orofacial infections occur)

Question 20

How does the bacterial load compare in the periapical tissues v the pulp in periapical lesions?

Answer 20

Low in the pulp (because its necrotic)

High in the periapical tissues

Question 21

Why are periapical leisons often asymptomatic?

Answer 21

The pulp is necrotic

Usually need a radiograph to detet

Question 22

Most periapical lesions are what?

Answer 22

Periapical granulomas

Question 23

Periapical granuloma

Answer 23

Asymptomatic inflammatory response
Macrophage dominant, but other inflammatory cells are also present
Often chronic

Question 24

Acute dentoalveolar (periapical) abscess

Answer 24

Acute exacerbation of periapical lesion
Purulent bacterial infection combined to bone at the apex
Very painful - aching, throbbing pain - tooth is sensitive to pressure
Drainage of pus may bring relief

Question 25

How can drainage of acute dentoalveolar abscesses occur?

Answer 25

Can occur through spontaneously through a fistula to surface or into tissue spaces Drainage into surrounding tissues is dangerous and can lead to orofacial involvment

Question 26

Palliative treatment

Answer 26

Aimed at relieving patient symptoms

Question 27

What are some Palliative treatments of pulpal and periapical diseases?

Answer 27

Pharmaologic treatment with analgesiscs and/or long-acting anesthetic agents Antibiotics are not effective against infections confined to the pulp or apical periodontitis because the blood supply is cut off and they can't get there

Question 28

Definitive treatment

Answer 28

Treatment aimed at riffing the patient of cause of infections

Question 29

What are definitive treatments of pulpal and periapical diseases?

Answer 29

Preferred treatment Extraction of the tooth OR Root canal

Question 30

Root canal treatment

Answer 30

Chemical and mechanical cleaning of the root canal system | Through cleaning and good coronal seal, it prevents access of substrates and re-infections

Question 31

Persistent apical lesion

Answer 31

Infections that occur after root canal therapy

Question 32

How can persistent apical lesions occur?

Answer 32

Biofilm may be present on the surface of tooth areas Debris ma remain within inaccessible regions of the apical canals Foreign body such as infected dentin fragments may have been displaced by over-instrumentation

Question 33

What is the treatment of persistent apical lesions?

Answer 33

External biofilms can be removed by conventional endo therapy Irregularly shaped apical foramina may be difficult or impossible to instrument from a coronal approach Apical debris cannot be reached by nonsurgical access Surgical therapy: "endodontic microsurgery" aka "apicoectomy"

Question 34

Odontogenic infections

Answer 34

When dental infections spread to surrounding areas, they're called odontogenic infections Range from localized to the alveolar area (dentinoalveolar area) to extending to adjacent facial structures or even systemic infections

Question 35

Cellulitis

Answer 35

Infection spreads through soft tissue via vascular channels or direct Tissue is swollen (edema) Tissue is hard (indurated) to palpaiton and not fluctuant

Question 36

What is the source of upper and lower facial cellulitis?

Answer 36

``` Lower = always dental Upper = dental about 1/2 the time ```

Question 37

What is the "2nd phase" that cellulitis may proceed to?

Answer 37

Abscess formation - fluctuant and errythematous - natural drainage may occur, but it will not resolve without drainage

Question 38

Microbiology of Cellulitis and dental abscesses

Answer 38

Polymicrobial (4-6 species) Cellulitis = facultative anaerobes Abscesses = anaerobic species Streps, peptostreps, prevotella, and sometimes fusobacterium

Question 39

How do you treat cellulitis?

Answer 39

May be temporarily managed with antibiotics Will resolve more quickly if source of infection is removed If it is well established, it may require antibiotics even after extraction of the tooth

Question 40

How do you treat abscesses?

Answer 40

If extraction or RCT doesn't provide drainage, surgical incision and drainage is required Penicillin and Clindamycin are two first line antibiotic chices

Question 41

Alveolar Osteitis

Answer 41

aka Dry Socket Delayed healing of extraciton site - clot doesn't form properly, exposing bone Biofilm forms on bone surface

Question 42

Alveolar osteitis symptoms

Answer 42

Swelling, redness, exposed bone Painful - throbing and aching Mal-odor, bad taste, oozing

Question 43

Alveolar osteitis treatment

Answer 43

Gentile debridement and medicated dressing

Question 44

Osteomyelitis of the jaw

Answer 44

Spread of odontogenic or periodontal infection to jaw Seen as a radiolucent area May be surrounded by incolcrum (radiopaqe walling off) Usually occurs in immunocompromised patients

Question 45

Osteomyelitis of the jaw symptoms

Answer 45

Swelling, pain, errythemia | Fever

Question 46

Osteomyelitis of the jaw treatment

Answer 46

Surgical debridement | Longterm antibiotic therapy

Question 47

Medication-induced Osteonecrosis of the jaw (MRONJ)

Answer 47

Exposed bone that does not heal Rare unless patient is in immunosupressive cancer treatment and high dose-IV antiresorptive agent after a dental infection/extraction Very rare

Question 48

Etiology of MRONJ

Answer 48

No osteoclasts, so non-shedding bone acts like a tooth and has reduced vascularity Biofilms accumulate on the bone

Question 49

Treatment of MRONJ

Answer 49

Remove biofilm by debridement Systemic antibiotics are ineffective Temporarily stop anti-resorptive drugs

Question 50

How can we prevent MRONJ?

Answer 50

Avoid dental extractions in immunocompromised patients with history of bisphosphonate Tx Maintain good oral health in at-risk patietnts Conservative surgical approaches Avoid bone exposure if possible Antimicrobial mouth rinses after surgery