Spread Of Infection

Question 1

What are the main treatment options for a dental abscess?

Answer 1

Extirpation
Incise and drain
Drain via perio pocket (if perio abscess)
Extraction

Question 2

When does an abscess require extra oral drainage?

Answer 2

If the infection has spread to buccal/ submandibular space.

Question 3

What anatomical structures should be considered when draining a lower lingual/ buccal and upper palatal swelling?

Answer 3

Lower lingual - lingual nerve - dont incise here
Lower buccal - mental nerve (in premolar region)
Palatal - greater palatine nerve

Question 4

How are anatomical structures avoided when incising?

Answer 4

Incise superficially and when incising on palate, incise in an antero-posterior direction

Question 5

Why is anaesthesia difficult to achieve in infection?

Answer 5

There is a low pH, therefore the LA becomes charged (ionised) and cannot cross the membrane to block the sodium channels.
Dissociation of LA is more difficult.

Question 6

Should the incised lesion be sutured closed? Why?

Answer 6

No, dont suture incision after drainage.
This allows further drainage and promotes healing.

Question 7

Describe the path of spread of infection from a lower 6, spreading buccally.

Answer 7

Infection travels from apex of the tooth.

Travels buccally:
If the infection perforates below the insertion of the buccinator muscle, infection will travel into buccal space.
If infection perforates above the insertion of the buccinator, the infection will travel into buccal sulcus (Intra oral).
Opposite for upper teeth.

Question 8

Describe the path of spread of infection from a lower 6, spreading lingually?

Answer 8

If the infection perforates below the insertion of mylohyoid muscle (usually only lower 8s), infection will travel into submandibular space.
If infection perforates above the insertion of mylohyoid, infection will travel into sublingual space.

Question 9

Describe the path of spread of infection from an upper 6, spreading palataly?

Answer 9

If infection from an upper tooth is travelling palatally, infection can spread to the sinus (chronic sinusitis) / palate (intra oral)

Question 10

How does infection progress from the submandibular/ sublingual space?

Answer 10

The mylohyoid muscle has no posterior attachment therefore, infection can travel backwards into masticatory space. This is a red flag sign.

Question 11

What spaces make up the masticatory space?

Answer 11

Submasseteric, pterygomandibular and infratemporal space.

Question 12

If infection is in masticatory space, what may the patient present with and what causes this?

Answer 12

Severe trismus
The infection is acidic, therefore causing the masticatory muscles to spasm.

Question 13

From the masticatory space, where can infection further travel? What will the patient present with?

Answer 13

Can spread even further back into lateral pharyngeal space (limited opening and pharynx pushed in)
And further into retropharyngeal space (difficulty swallowing and breathing)

Question 14

How can a dental infection cause compression on the heart?

Answer 14

Infection can spread from submandibular space, to masticatory spaces, to retropharyngeal spaces which communicate with superior medialstinum (compresses heart).

Question 15

How can a microbial sample be taken for a dental abscess?

Answer 15

Swab
Pus aspirate

Question 16

What is the best method for microbial sampling and why?

Answer 16

Pus aspirate - less contamination from oral cavity, microorganisms stored and travel in aerobic conditions.

Question 17

On clinical exam, what should you feel for when patient presents with large swelling? What does this show?

Answer 17

Palpate for border of the mandible as this shows if infection has spread into submandibular space.

Question 18

From phone assessment, what are some red flag symptoms?

Answer 18

Difficulty breathing
Eye closure
Drooling
Elevated tongue
Hoarseness

Question 19

What is Ludwig’s angina?

Answer 19

Bilateral cellulitis of sublingual and submandibular spaces.
When infection crosses the midline, urgent referral to maxfacs.

Question 20

What special investigations should be considered when a patient presents with an abscess?

Answer 20

Pulp sensibility testing
Tender to percussion
Mobility
IO radiographs

Question 21

What are common bacteria isolated from acute dento alveolar abscesses? And which antibiotic is effective against each?

Answer 21

Streptococci - penicillin and erythromycin/ clindomycin
Strict anaerobes - penicillin and metronidazole

Question 22

If signs of spreading infection, what investigations should be carried out?

Answer 22

Temperature
Pulse
Respiratory rate
BP
Oxygen saturation

Question 23

What is SIRS and how is it diagnosed?

Answer 23

Systemic inflammatory response syndrome
Diagnosed when patient presents with 2/4:
- temperature <36 or >38
- heart rate >90 bpm
- respiratory rate >20 breaths per min
- WCC <4000 or >12,000

Question 24

What is sepsis?

Answer 24

Life threatening condition caused by over reaction of the bodys immune response to infection (SIRS + infection).

Question 25

What factors influence the path of infection spread?

Answer 25

Location of infection
Thickness of bone, muscle and facial attachments

Question 26

If pt with pleading infection was to be admitted to hospital, how might they be managed?

Answer 26

ABC
Signs and symptoms of sepsis (sepsis 6) and ressuscitation if appropriate
Intravenous antibiotics (benzoyl penicillin and metronidazole)
Incision and drainage under GA (and extraction of potentially infected teeth)
Pus aspirate