Bacterial Infection of the Orofacial Tissues

Question 1

What is the physiology of a submandibular space infection?

Answer 1

An infection of the tooth that travels from the tooth to the periapical tissues surrounding the tooth and then travels further entering below the mylohyoid muscle into a fascial space

Question 2

What is the physiology of a sublingual space infection?

Answer 2

An infection of the tooth that travels from the tooth to the periapical tissues surrounding the tooth and then travels further entering above the mylohyoid muscle into the sublingual space

Question 3

What is the physiology of a facial space infection?

Answer 3

An infection of the tooth that travels from the tooth to the periapical tissues surrounding the tooth and then travels laterally past the buccinator muscle into a fascial space

Question 4

What is the physiology of a sub-masseteric space infection?

Answer 4

An infection of the tooth that travels from the tooth to the periapical tissues surrounding the tooth and then travels laterally entering the fascial space between the mandible and the masseter muscle, collecting below the muscle

Question 5

What different types of infections could result from an infected LR6

Answer 5

Gingival abscesses
Submandibular space infections
Sublingual space infections
Facial space infections
Sub-masseteric space infections
Mediastinitis

Question 6

What different types of infections could arise from an infected UR4?

Answer 6

Gingival abscesses
Facial space infections
Sinusitis
Cavernous sinus thrombosis

Question 7

Name the 4 factors that need to be in balance with one another in order to maintain health

Answer 7

Bacterial virulence factors
Bacterial load

Host defences (physical e.g., skin, mucosa and saliva, chemical e.g., inflammatory/immune system)
Antibiotics

Question 8

Name the additional 2 factors that can tip the balance that maintains health to either make a host more vulnerable to infections or less vulnerable to infections . Why does either factor act in this way?

Answer 8

Blood supply to the head and neck - more able to fight off infection. Fresh blood supply to the head and neck allows a constant supply of nutrients such as WBCs, RBCs, platelets, complement factors, antibiotics that can fight off bacterial load

Fascial spaces - less able to fight off infection. Fascial spaces do not contain a blood supply of their own so the beneficial substrates within the blood cannot reach the fascial spaces to eliminate an infection. These spaces are ‘potential’ spaces that have the ability to open up quite rapidly and communicate with other spaces. This allows bacteria to spread through these spaces rapidly making an infection even more dangerous and broad

Question 9

What are the 5 cardinal signs of inflammation/infection?

Answer 9

Calor (hot)
Dolor (painful)
Rubor (redness)
Tumor (swelling)
Functio Laesi (loss of function)

Question 10

Define an abscess

Answer 10

Localised collection of bacteria, dead tissue and WBCs

Question 11

Define pus

Answer 11

Collection of bacteria, dead tissue and WBCs

Question 12

Define cellulitis

Answer 12

Spreading infection of the skin, diffuse ill defined redness of the skin, minimal swelling, with no pus initially. But if the infection persists, the affected tissues may break down/become undermined and pus may begin to collect after a few days

Question 13

What are the local signs of an infection?

Answer 13

Heat
Redness
Swelling
Induration (hardness)
Pain

Question 14

What are the regional signs of an infection?

Answer 14

Trismus
Dysphagia
Difficulty breathing
Lymphadenopathy (reactive lymph nodes)

Question 15

What is trismus and why does it occur during some infections?

Answer 15

Limited mouth opening. Loss of function of the muscles that enable mouth opening due to inflammation

Question 16

Why may patients find it difficult to breathe during some infections?

Answer 16

Swelling in the head and neck region as a response to infection could obstruct the airway

Question 17

How can we determine the presence of pus?

Answer 17

Clinical inspection/suspicion, check for a fluctuant swelling (apply pressure and feel for fluid movement). Should feel like a soft fluid filled bag. May be suppurating with a yellow discharge

Aspirate pus using an aspirating needle - but if pus is very thick and sticky it may be difficult to aspirate

Spiking temperature - requires constant monitoring to confirm increasing temperature, not always possible in a primary care setting. Sometimes, lower temperatures seen e.g., severe case of sepsis

Ultrasound

CT scan

Question 18

Why are dental infections important if most are not life-threatening?

Answer 18

Not always able to differentiate between a trivial and life-threatening infection. This poses a significant risk of morbidity and mortality

Can impact the airway relatively quickly

If they affect the face, their treatment and management e.g. draining via extra-oral route, post-surgical scarring can lead to cosmetic complications

Complications related to local spread of the infection can occur e.g. trismus

Dental infections can be confused with other infections such as those caused by ENT disease, skin disease, neurological disease and other diseases related to local anatomy

Risk of sepsis which can causes multiple organ failure and eventual death

Question 19

Describe Carvenous Sinus Thrombosis

Answer 19

The cavernous sinus is a cavity inside the brain which drains blood as part of the venous drainage system of the head and neck. This sinus is situated at the back of the eyes, near the optic chiasma.

If we get bacteria in this sinus, it can trigger a coagulation within the sinus. The blood coagulation cascade is essentially triggered by the bacterial toxins/antigens/foreign material within the blood. This can cause the whole sinus to thrombose.

This will cause a lack of venous drainage from the affected eye which will lead the eye/orbit to become engorged. Clinically, this will present as a swollen, painful red eye with conjunctiva that appears very swollen and oedematous looking.

Question 20

How can an infection of a LL5 become life-threatening and affect the function of the heart?

Answer 20

If left untreated, this infection can erode through the cortical plate and travel below the mylohyoid muscle to become a submandibular space infection.

If this fascial space infection is not drained, the bacteria in the infection can develop into the pus and the pus can start to ferment and produce gas opening up the potential fascial space.

And because of the pressure produced by the gas, the pus can be forced from this space into the parapharyngeal space which directly communicates with the mediastinum which is a space in the chest that contains many important organs including the heart.

This is potentially very dangerous as once we get infection in this space, we can get pus in the mediastinum which can interfere with the heart, the great vessels of the chest and with gas exchange in the lungs.

Question 21

What is the physiology of a gingival abscess?

Answer 21

An infection of the tooth that travels from the tooth to the periapical tissues surrounding the tooth and then travels further with the pus eroding through the cortical bone and entering the gingival space

Question 22

List the clinical signs and symptoms of a sublingual space infection

Answer 22

A lot swelling in the floor of the mouth

Elevation of the floor of the mouth secondary to the swelling causing the tongue to be raised upwards

Floor of mouth feels painful and tense when palpated

Fever, systemically unwell

Drooling

Dysphagia

Question 23

List the clinical signs and symptoms of a submandibular space infection

Answer 23

Swelling of the lower face and upper neck region on affected side

Pain and tenderness in lower jaw

Fever, systemically unwell

Question 24

List the clinical signs and symptoms of a facial space infection

Answer 24

Swelling that begins at the lower border of the mandible and ascends all the way up to the lower eye lid on the same side

Pain

Fever, systemically unwell

Question 25

What is the challenge with facial space infections?

Answer 25

Difficult to determine the origin of the infection. Could be any of the following:

Infection of an upper tooth
Infection of a lower tooth
Orbital cellulitis

Question 26

List the clinical signs and symptoms of a sub-masseteric space infection

Answer 26

Mild swelling (as infection is constrained below the masseter muscle)

Profound trismus (the infection underneath the masseter muscle leads to inflammation which causes the muscle to lose function and spasm, no longer being able to open to its full limit)

Pain

Fever, systemically unwell

Question 27

Why is trismus significant? Why do affected patients require referral to secondary care?

Answer 27

If a patient cannot open their mouth fully, a dentist cannot remove the infected tooth under LA.

If a patient is indicated for GA, the anaesthetist will not be able to visualise the vocal chords very easily to intubate the patient for the procedure if they are unable to open their mouth.

Question 28

Another name for a sub-masseteric space infection. Why is this a potentially life-threatening infection?

Answer 28

Masticator space infection

The masticator space directly communicates with the lateral pharyngeal space. The lateral pharyngeal space is in direct communication with the parapharyngeal space.

The parapharyngeal space is the link between the head and neck and the mediastinum. Any bacterial infection can travel from the masticator space into the mediastinum very quickly if the pus within the infection begins to ferment and produce gas leading to mediastinitis. This can affect the organs within the mediastinum including the heart, great vessels of the chest and the lungs

Question 29

What can palatal abscesses be mistaken for?

Answer 29

Palatal tumours or growths

Question 30

Why are palatal abscesses commonly associated with molars and incisors, particularly U2/6s?

Answer 30

Roots of these teeth often curve palatally

Question 31

How would you approach a patient who presents with a swelling of the lower face and upper neck + associated toothache, fever and malaise?

Answer 31

History-taking:
Inquiry into potential source of infection e.g., has the patient had a history of toothache, recent XLAs, recent dental trauma leading to a broken tooth?

Examination:
Assess for local, regional and systemic signs of inflammation
ABC assessment

Special Investigations:
X-rays (PA/OPT/USS/CT)

Determine differential diagnosis (is the infection an abscess or cellulitis?) and treat accordingly.

Question 32

What are the different X-rays that may be taken when we suspect a patient with a dental bacterial infection?

Answer 32

PA
OPT
Ultrasound scan
CT scan

Question 33

In what situations would you refer the patient to secondary care in a hospital setting (call an ambulance)?

Answer 33

Life-threatening ABC on assessment e.g.,

Difficulty breathing

Difficulty swallowing and speaking are indicative of a potential and impending airway problem

Trismus (e.g., where a patient has a submasseteric facial space infection)

Bilateral submandibular space infections with or without associated sublingual space infections (Ludwig’s angina)

Question 34

How do we manage a fluctuant infected swelling adjacent to a non-vital LR5?

Answer 34

As the swelling is fluctuant, it will contain pus. This needs to be drained as soon as is practical with a relieving incision into the swelling followed by drainage.

The source of infection needs to be removed e.g., the LR5 either needs to be XLA’d or RCT’d if restorability allows and the patient wants to hold on to the tooth

Antibiotics only as part of definitive treatment once a differential diagnosis has been made and antibiotics are actually indicated (pain, fluctuant swelling/evidence of pus, cellulitis, or regional/systemic effects e.g., fever, malaise, lymphadenopathy and other indications of systemic unwellness)

Analgesia/antipyretics (for pain and fever)

Question 35

How do the treatments for cellulitis and abscess differ from one another?

Answer 35

Cellulitis alone treated with antibiotics

Abscess alone treated with incision and drainage

Question 36

Why may adequate anaesthesia be difficult to achieve for teeth with abscesses. How can this be managed?

Answer 36

Due to acidic pH and inflammation within the target site.

LA given to a site that is at a distance from the abscess or given directly into the surface layer of the abscess only to make the incision

Ethyl Chloride used to freeze the area of incision (cold has analgesic effects)

If adequate analgesia cannot be obtained, we would need to explain to the patient the potential of pain for a second, whilst just proceeding with an incision through the mucosa.

Question 37

Why is there potential to see no pus when making an incision during the management of a gingival/buccal abscesses.

Answer 37

As the pus erodes through the cortical bone from an infected tooth, we would need to go down to the level of the alveolar bone when making an incision in order to release the pus

Question 38

What are the standard antibiotics to use in a patient with an UL2 dental bacterial infection?

Answer 38

Amoxicillin 500 mg 3x a day
Metronidazole 400 mg 3x a day

Question 39

What are the standard antibiotics to use in a patient with an UL2 dental bacterial infection and a penicillin allergy?

Answer 39

Erythromycin 500 mg 4x a day

Question 40

What would you do for a patient with a neck swelling and evidence of an associated dental bacterial infection?

Answer 40

Drainage via extra-oral route using 2 finger breadths measurement from the lower border of the mandible.

The 2 finger breadth measurement is used to prevent severing the marginal mandibular branch of the facial nerve as this would cause permanent facial weakness.

Removal of the source of infection

Antibiotics

Analgesia and antipyretics if fever

Question 41

Why do bilateral submandibular space infections require hospital referral?

Answer 41

Airway can become compromised very quickly if left untreated, due to the swellings on either side of the airway which can impede it

Question 42

What is a bacterial virulence factor? List some along with their function

Answer 42

Those factors that make the bacteria more harmful or invasive

E.g.,
Antigenicity, enzyme production

Adhesin - factor that allows binding to host cell/tissue

Invasin- factor that allows invasion of host cell/tissue

Modulin - factor that induces indirect damage by perturbing the regulation of host defences

Impedin - factor that allows avoidance of host defence mechanisms

Aggressin - factor that causes direct damage to host

Question 43

An infection presenting on the skin could be 1 of 3 things. Name them.

Answer 43

Skin infection
An infection tracking to the skin from an underlying dental infection
Salivary gland tissue infection

Question 44

Describe the following:

Folliculitis
Boil
Carbuncle
Furuncle

Answer 44

A little of inflammation/infection around the hair follicle, leading to redness confined to the skin immediately around the hair follicle

Hair follicle becomes blocked and the folliculitis infection persists leading to the tissue within the follicle becoming infected as well.

More and more follicles adjacent to one another become involved with the infection

Infection of the follicles has spread and began to undermine the tissues

Question 45

Define Erisypelas?

Answer 45

Superficial spreading Streptococcal infection of the skin

Leads to oedema/cellulitis of the dermis (2nd layer of skin)

May also cause patient to become systemically unwell

Question 46

What is the causative microbe of Erisypelas?

Answer 46

Streptococcus bacteria

Question 47

How is a patient with Erisypelas treated?

Answer 47

Antibiotics.

Can measure the rate of the infection by drawing a line around the erythmatous margins on the face. If after a while, the erythema spreads beyond this line, it indicates a very aggressive infection that requires either more antibiotics, more aggressive antibiotics or a need to seek advice from a microbiologist.

Highly infectious infection and therefore a dentist should send the patient back home as soon as practical to prevent spread

Question 48

Define Impetigo

Answer 48

Streptococcal/Staphylococcal infection of the skin.

Leads to the formation of vesicles on the skin which can be tender, red and painful. These can rupture to produce a very clear yellow golden exudate. Eventually crust over (yellow/gold crushing).

Contagious infection, therefore patients or staff with it will need to be sent home

Question 49

What is the first line of management when a patient presents with a recurring infection of the skin that does not heal following standard management?

Answer 49

Consider possibility of underlying dental infection that is tracking through the skin.

Take a historic pain history and a PDH-

Has the patient had historic pain in one of his teeth?

Has the patient had any large/deep fillings in one of his teeth?

Conduct an EO l/IO examination-

Palpate the region of infection and see whether it can be tracked back to the buccal aspect of the apex of a tooth that is visibly carious/broken down/radiographically infected or traumatised.
May observe a palpable sinus track

During palpation of the skin infection, it may feel fixed to the bone (indicating underlying dental infection)

Undertake special investigations-

Place a GP point into the swelling and take a PA radiograph, GP point will confirm which tooth is non-vital.

Question 50

Define Sepsis

Answer 50

A life-threatening complication of an infection, more commonly occurring in those with some form of immunocompromise.

Can have detrimental effects on the heart, respiratory system, liver, kidney, blood of an individual.

Can cause morbidity as well as mortality.

Question 51

Which groups are at greater risk of Sepsis from a normally trivial infection?

Answer 51

Very young as they have a developing immune system

Very old as they often have a compromised or failing immune system

Neutropenic patients (those with low WBCs, those who have had or are having chemotherapy/radiotherapy of head/neck)

Immunocompromised/suppressed patients (those taking large doses of steroids or methotrexate or biological response modifier medications for inflammatory diseases such as RA)

Intravenous drug abusers

Question 52

What can happen to the body during Sepsis?

Answer 52

Cardiovascular issues- can induce heart failure or difficulty in maintaining adequate BP (often drops <100, making the patient hypotensive)

Respiratory issues- can cause oedema/fluid build up in the lungs as a result of heart failure making it difficult to breathe with sufficient oxygen (often results in raised respiratory rate >20bpm)

Liver failure/kidney failure

Issues with blood-
Production of too many or too little platelets. Production of too many WBCs or too little (as they’re being consumed by the infection)

Neurological symptoms-
Altered mental state/behaviour (e.g., acute confused state, restlessness or drowsiness)

Question 53

If a patient attended and was experiencing Sepsis, what would you observe clinically?

Answer 53

Altered mental state or behaviour (especially in elderly). Acute confusion, restlessness or drowsiness

Raised respiratory rate >20 bpm

Raised pulse rate >90 bpm

Low blood pressure <100 mmHg

Patient reports no passage of urine within last 12 hours (indicative of kidney failure)

Temperature <36

Skin appears mottled or ashen. Non-blanching rash evident alongside signs of potential skin infection

Question 54

Define Necrotising Fasciitis

Answer 54

A Streptococcal infection of the skin that normally occurs due to the presence of trivial wound/infection site.

Bacteria produces toxins which activate the complement cascade/coagulation cascade and this causes necrosis of the tissues. As the bacteria spreads rapidly through the tissues, it can cause the tissues to become undermined.

Patient becomes systemically unwell

Question 55

Who should we have a lower index of suspicion for when suspecting necrotising fasciitis?

Answer 55

Elderly
Immunocompromised

Question 56

Define Actinomycosis

Answer 56

A chronic non-healing infection affecting the skin that is characterised by a low grade fever, weight loss, cough and general unwellness.

Caused by oral commensals.

Question 57

A patient attends your clinic complaining of a non-healing socket post-extraction. On further inquiry, the patient reports feeling really unwell for the past couple of weeks, with a low grade fever and cough. The patient feels he has also lost some weight.

A clinical inspection reveals the patient has a swelling on their face that seems to be leaking some fluid.

What is your provisional diagnosis? How will you confirm it?

Answer 57

Actinomycosis

Inspect the fluid for the presence of yellow granules (sulfur granules which are characteristic of Actinomycosis)

Take a swab of the leaking fluid from the swelling and send it to microbiology for analysis. Should reveal gram positive branching filaments using microscopy

Question 58

How would you treat a patient with Actinomycosis?

Answer 58

Surgery, followed by antibiotics.

Surgery to decompress the area and drain the pus. Offending tooth will need to be removed alongside any infected tissue.

Antibiotics should follow surgery

Question 59

I am a rare bacterial infection that affects 1 in 300,000 individuals in the UK. I am caused by an oral commensal. My symptoms include a chronic, non-healing, scarring infection that affects the skin and induced leaking fluid. What am I? In what situations may I occur?

Answer 59

Actinomycosis.

Where there is:

A non-healing socket post-extraction

A chronic dental infection at the apex of a tooth

A wisdom tooth extraction

Within a fracture site following a fracture

A non-healing wound or infection

Question 60

Define ANUG

Answer 60

Refers to acute necrotising ulcerative gingivitis.

An infection that begins at the papillae of the gingivae and spreads along the gingival margin, cause gingival necrosis.

Question 61

What is another term for ANUG

Answer 61

Vincent’s stomatitis

Trench mouth

Question 62

Who is more likely to experience ANUG?

Answer 62

Patients who:

Are smokers

Have poor OH

Are stressed

Suffer from some form of immunocompromised

Are malnourished

Question 63

Describe the clinical signs and symptoms of ANUG

Answer 63

Bad breath due to necrosis of the gingivae

Flattening/blunting of the papillae

Extensive bleeding and marginal gingivitis (severely red and inflamed gums)

Ulcers

Grey/dark slough surrounding gingival margins indicating necrosis